U.S. patent application number 12/818522 was filed with the patent office on 2011-05-12 for computer-aided design of a thin-layer drill guide.
Invention is credited to Jerome Haber.
Application Number | 20110111371 12/818522 |
Document ID | / |
Family ID | 43974418 |
Filed Date | 2011-05-12 |
United States Patent
Application |
20110111371 |
Kind Code |
A1 |
Haber; Jerome |
May 12, 2011 |
COMPUTER-AIDED DESIGN OF A THIN-LAYER DRILL GUIDE
Abstract
A drill guide uses a hole in a layer to guide a drill along an
axial trajectory while permitting off-axis excursions of the drill
during use. A number of such drill guides at varying heights from a
target surface may be used sequentially or concurrently to enforce
the axial trajectory in three dimensions during a surgical
operation. A drill guide may include a hole in a layer that
establishes a single point along the axial trajectory, or the drill
guide may include multiple layers in a single device to establish
two or more points along the trajectory while allowing off-axis
insertion of a drill into the guide. The drill guide may be
cuttable to accommodate intraoperative changes to the axial
trajectory. In embodiments, a window or the like may be provided to
permit a surgeon to view drill depth, drill orientation, the
surgical site and the like during a procedure.
Inventors: |
Haber; Jerome; (Weston,
MA) |
Family ID: |
43974418 |
Appl. No.: |
12/818522 |
Filed: |
June 18, 2010 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
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12816710 |
Jun 16, 2010 |
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12818522 |
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61260065 |
Nov 11, 2009 |
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Current U.S.
Class: |
433/201.1 ;
378/4 |
Current CPC
Class: |
A61C 1/084 20130101;
B33Y 80/00 20141201 |
Class at
Publication: |
433/201.1 ;
378/4 |
International
Class: |
A61C 8/00 20060101
A61C008/00; A61B 6/03 20060101 A61B006/03 |
Claims
1. A method comprising: obtaining three-dimensional data from
beneath a surface of a surgical site; determining an axial
trajectory for an implant to be placed in the surgical site based
upon the three-dimensional data; and fabricating a device for
guiding a tool in a dental procedure based upon the
three-dimensional data, the device including a support fitted to an
area around the surgical site and a surgical guide including a hole
that aligns the tool to the axial trajectory at a first point along
the axial trajectory while permitting off-axis excursions of the
tool from the axial trajectory at a second point along the axial
trajectory away from the hole when the surgical guide is placed for
use at the surgical site.
2. The method of claim 1 wherein fabricating the device includes
manually fabricating the support and applying the three-dimensional
data to create the hole in the surgical guide.
3. The method of claim 1 wherein fabricating the device includes
applying the three-dimensional data to generate a digital model of
the surgical guide including the hole and fabricating the surgical
guide from the digital model.
4. The method of claim 1 wherein determining the axial trajectory
for the implant includes positioning an implant with implant
planning software.
5. The method of claim 1 wherein fabricating the device includes
applying the three-dimensional data to create the hole in the
digital model of the device.
6. The method of claim 1 wherein fabricating the device includes:
capturing a physical impression of the surgical site; using the
physical impression to fabricate a physical model; and using the
physical model to manually fabricate the device.
7. The method of claim 6 wherein obtaining three-dimensional data
includes obtaining x-ray tomography data of the device and applying
the three-dimensional data to create a digital model of the
device.
8. The method of claim 7 wherein fabricating the device includes
applying the three-dimensional model to a computerized fabrication
system to fabricate the surgical guide.
9. The method of claim 6 further comprising creating the hole in
the surgical guide with a computer-controlled machine.
10. The method of claim 9 wherein the computer-controlled machine
includes a computer-controlled drilling machine.
11. The method of claim 1 wherein obtaining three-dimensional data
includes obtaining x-ray tomography data from the surgical
site.
12. The method of claim 1 wherein obtaining three-dimensional data
includes creating a digital three-dimensional surface model of the
surgical site.
13. The method of claim 12 wherein obtaining three-dimensional data
includes creating a digital three-dimensional surface model of a
full dental arch, and wherein fabricating the device includes using
the digital three-dimensional surface model to fabricate the device
using a computerized fabrication system.
14. The method of claim 13 wherein the computerized fabrication
system includes a stereolithography system.
15. The method of claim 1 wherein fabricating the device includes
forming a material to a physical model of a dental arch containing
the surgical site.
16. The method of claim 1 wherein fabricating the device includes
fabricating the support to secure the surgical guide in a desired
location relative to the surgical site.
17. The method of claim 16 wherein the support includes a surface
formed to dentition around the surgical site, thereby providing
tooth support for the surgical guide.
18. The method of claim 17 wherein the surface is formed to a full
arch containing the surgical site.
19. The method of claim 16 wherein the support provides soft tissue
support for the surgical guide.
20. The method of claim 1 wherein fabricating the device includes
fabricating a two-layer surgical guide having a first hole in a
first layer centered around a first point on the axial trajectory
and a second hole in a second layer centered about a second point
on the axial trajectory.
21. The method of claim 20 wherein obtaining three-dimensional data
includes obtaining a digital three-dimensional surface model of the
surgical site.
22. The method of claim 21 wherein fabricating the device includes
using the digital three-dimensional surface model to fabricate the
surgical guide using a computerized fabrication system.
23. The method of claim 20 wherein fabricating the device includes
fabricating a window between the first layer and the second
layer.
24. The method of claim 1 wherein fabricating the device includes
fabricating the device with a plurality of holes for a plurality of
axial trajectories.
25. The method of claim 1 further comprising fabricating a
plurality of devices each including a progressively larger diameter
hole shaped and positioned to align one of a number of
progressively larger diameter drills to the first point on the
axial trajectory.
26. The method of claim 1 wherein the device includes a thin layer
surgical guide having a layer including the hole, and wherein the
hole is vertically spaced apart from the surface of the surgical
site when the device is placed for use, and wherein fabricating the
device further includes fabricating a window between the layer and
the surface for at least one of physical access to the surgical
site and visual access to the surgical site when the device is
placed for use.
Description
RELATED APPLICATIONS
[0001] This application is a continuation of U.S. application Ser.
No. 12/816,710 filed Jun. 16, 2010 which claims the benefit of U.S.
Prov. App. No. 61/260,065 filed on Nov. 11, 2009, each of which is
hereby incorporated by reference.
BACKGROUND
[0002] The invention relates to surgical drill guides for use in
dental surgery and similarly constrained surgical and/or drilling
operations.
[0003] Drill guides are commonly used by dental surgeons to align a
drill or other cutting tool with an intended hole for a dental
implant; however, existing drill guides have significant
disadvantages. For example, some drill guides require insertion of
a drill in alignment with a cutting trajectory, which can present
difficulties in confined spaces that offer little clearance or
overhead. As another disadvantage, some drill guides block a
surgeon's view of the location where a drill meets bone or other
tissue, thus impairing the surgeon's ability to obtain adequate
visual verification of drill position and depth.
[0004] There remains a need for improved drill guide devices and
methods for use in dental surgery and similarly constrained
surgical and/or drilling operations.
SUMMARY
[0005] A drill guide uses a hole in a layer to guide a drill along
an axial trajectory while permitting off-axis excursions of the
drill during use. A number of such drill guides at varying heights
from a target surface may be used sequentially or concurrently to
enforce the axial trajectory in three dimensions during a surgical
operation. A drill guide may include a hole in a layer that
establishes a single point along the axial trajectory, or the drill
guide may include multiple layers in a single device to establish
two or more points along the trajectory while allowing off-axis
insertion of a drill into the guide. The drill guide may be
cuttable to accommodate intraoperative changes to the axial
trajectory. In embodiments, a window or the like may be provided to
permit a surgeon to view drill depth, drill orientation, the
surgical site and the like during a procedure.
[0006] In one aspect, a device disclosed herein includes: a
surgical guide for a dental procedure, the surgical guide including
a first hole in a first layer, the first hole positioned to align a
tool to an axial trajectory at a first point along the axial
trajectory and the surgical guide including a second hole in a
second layer, the second layer vertically spaced apart from the
first layer along the axial trajectory and the second hole
positioned to align the tool to the axial trajectory at a second
point along the axial trajectory; and a support to secure the
surgical guide in relation to a location where the axial trajectory
meets a target surface of a surgical site.
[0007] The target surface may include one or more of soft tissue
and bone. The target surface may include one or more of gingiva and
a jawbone. The surgical site may include a dental implant site. The
axial trajectory may be a trajectory of a surgical drill into a
surgical site. The axial trajectory may be a trajectory of a
surgical drill into a dental implant site. The first hole and the
second hole may be shaped and sized to align an object to the axial
trajectory including one or more of a drill, a surgical drill, a
rotary tool, and a surgical hand tool. The support may include a
surface formed to dentition around the surgical site, thereby
providing tooth support for the surgical guide. The surface may be
formed to a full arch containing the surgical site. The support may
include a surface formed to bone around the surgical site, thereby
providing bone support for the surgical guide. The support may
include one or more bone attachment points for securing the device
to a jawbone. The support may include a surface formed to soft
tissue around the surgical site, thereby providing soft tissue
support for the surgical guide. The support may be shaped and sized
to provide gingival support for the surgical guide. The support may
be shaped and sized to provide skin support for the surgical guide.
The first layer may contact the target surface in an area
surrounding the first hole when the device is placed for use at the
surgical site. The second layer may be spaced apart from the target
surface in an area surrounding the second hole when the device is
placed for use at the surgical site.
[0008] The second hole may have a diameter larger than the first
hole. The device may further include a space between the first
layer and the second layer that permits an insertion of the tool
off-axis from the axial trajectory. The second layer may include
one or more visible alignment marks to assist a user in locating a
center of the first hole. The first layer may include one or more
additional visible alignment marks to assist the user in locating a
center of the second hole. The device may include an opening for
physical access to a space between the first layer and the second
layer. The device may include an opening for physical access to the
surgical site. The device may include a window for visual
inspection of the target surface while the surgical guide may be in
use. The device may include a window for visual inspection of the
axial trajectory between the first layer and the second layer. The
device may be fabricated from a cuttable material. The axial
trajectory may be modified by enlarging one or more of the first
hole and the second hole. The device may include a plurality of
holes in each of the first layer and the second layer for a
plurality of axial trajectories.
[0009] The device may include a plurality of devices each including
a third hole positioned to align one of a number of progressively
larger diameter drills to the first point on the axial trajectory.
Each of the plurality of devices further may include a fourth hole
positioned to align one of the number of progressively larger
diameter drills to the second point on the axial trajectory. At
least one of the first hole and the second hole may have a sleeve
that protects the surgical guide against a cutting edge of the
tool. The sleeve may be formed of a material including one or more
of a steel, a titanium, a glass, a plastic, and an aluminum. The
surgical guide and the support may be formed of a clear material.
The second hole may have a larger diameter than the first hole, the
second hole sized to accommodate a drill stop and the first hole
sized to accommodate a drill without the drill stop.
[0010] In another aspect, a method disclosed herein include
obtaining three-dimensional data from beneath a surface of a
surgical site; determining an axial trajectory for an implant to be
placed in the surgical site based upon the three-dimensional data;
and fabricating a device based upon the three-dimensional data, the
device including a support fitted to an area around the surgical
site and a surgical guide including a hole that aligns a tool to
the axial trajectory at a first point along the axial trajectory
while permitting off-axis excursions of the tool from the axial
trajectory at a second point along the axial trajectory away from
the hole when the surgical guide may be placed for use at the
surgical site.
[0011] Fabricating the device may include manually fabricating the
support and applying the three-dimensional data to create the hole
in the surgical guide. Fabricating the device may include applying
the three-dimensional data to generate a digital model of the
surgical guide including the hole and fabricating the surgical
guide from the digital model. Determining the axial trajectory for
the implant may include positioning an implant with implant
planning software. Fabricating the device may include applying the
three-dimensional data to create the hole in the digital model of
the device. Fabricating the device may include: capturing a
physical impression of the surgical site; using the physical
impression to fabricate a physical model; and using the physical
model to manually fabricate the device. Obtaining three-dimensional
data may include obtaining x-ray tomography data of the device and
applying the three-dimensional data to create a digital model of
the device. Fabricating the device may include applying the
three-dimensional model to a computerized fabrication system to
fabricate the surgical guide. The method may include creating the
hole in the surgical guide with a computer-controlled machine. The
computer-controlled machine may include a computer-controlled
milling machine. The computer-controlled machine may include a
computer-controlled drilling machine. The computer-controlled
machine may include one or more of a hole punch and a heated
probe.
[0012] Obtaining three-dimensional data may include obtaining x-ray
tomography data from the surgical site. Obtaining three-dimensional
data may include creating a digital three-dimensional surface model
of the surgical site. Obtaining three-dimensional data may include
creating a digital three-dimensional surface model of at least a
portion of a dental arch. Obtaining three-dimensional data may
include creating a digital three-dimensional surface model of a
full dental arch. Fabricating the device may include using the
digital three-dimensional surface model to fabricate the device
using a computerized fabrication system. The computerized
fabrication system may include a stereolithography system. The
computerized fabrication system may include a computerized milling
machine. Fabricating the device may include forming a material to a
physical model of a dental arch containing the surgical site.
Forming the material to the physical model may include forming a
sheet of material onto the physical model. Forming the material to
the physical model may include vacuum forming a plastic sheet onto
the physical model. The surgical site may include one or more of
soft tissue and bone. The surgical site may include one or more of
gingiva and a jawbone. The axial trajectory may be a trajectory of
a surgical drill into the surgical site. The axial trajectory may
be a trajectory of a surgical drill into a dental implant site. The
method may include adding one or more visible alignment marks to
assist a user in locating a center of the hole. Fabricating the
device may include fabricating the surgical guide from a clear
material. Fabricating the device may include fabricating the
support to secure the surgical guide in a desired location relative
to the surgical site. The support may include a surface formed to
dentition around the surgical site, thereby providing tooth support
for the surgical guide. The surface may be formed to a full arch
containing the surgical site. The support may provide bone support
for the surgical guide.
[0013] The method may include adding one or more bone attachment
points to the support for securing the support to a jawbone,
thereby providing bone support for the surgical guide. The support
may provide soft tissue support for the surgical guide. The support
may provide gingival support for the surgical guide. The support
may provide skin support for the surgical guide.
[0014] Fabricating the device may include fabricating a two-layer
surgical guide having a first hole in a first layer centered around
a first point on the axial trajectory and a second hole in a second
layer centered about a second point on the axial trajectory.
Obtaining three-dimensional data may include obtaining a digital
three-dimensional surface model of the surgical site. Fabricating
the device may include using the digital three-dimensional surface
model to fabricate the surgical guide using a computerized
fabrication system. The computerized fabrication system may include
a stereolithography system. The computerized fabrication system may
include a computerized milling machine. The axial trajectory may
intersect a target surface of the surgical site when the surgical
guide may be placed for use at the surgical site and the second
layer may be vertically spaced apart from the target surface in a
second area surrounding the second hole. The first layer and the
second layer may be vertically spaced apart to provide a space that
permits an insertion of the tool off-axis from the axial
trajectory. Fabricating the device may include fabricating a window
for physical access to a space between the first layer and the
second layer. Fabricating the device may include fabricating a
window for visual inspection of a target surface while the surgical
guide may be in use. Fabricating the device may include fabricating
a window for visual inspection of the axial trajectory between the
first layer and the second layer.
[0015] Fabricating the device may include fabricating the device
from a cuttable material wherein the axial trajectory can be
modified by enlarging the hole. Fabricating the device may include
fabricating the device with a plurality of holes for a plurality of
axial trajectories. Fabricating a plurality of devices each
including a progressively larger diameter hole shaped and
positioned to align one of a number of progressively larger
diameter drills to the first point on the axial trajectory. The
method may include adding a sleeve to the hole that protects the
surgical guide against a cutting edge of the tool. The sleeve may
be formed of a material including one or more of a steel, a
titanium, a glass, a plastic, and an aluminum. Fabricating the
device may include fabricating a window for visual inspection of
the surgical site. Fabricating the surgical guide may include
fabricating a window for physical access to the surgical site.
[0016] In another aspect, a method for realizing an axial
trajectory of a cutting process disclosed herein includes: guiding
a first cutting tool with a first guide at a first point along the
axial trajectory when the first guide may be positioned for use at
a surgical site while permitting movement of the first cutting tool
away from the axial trajectory at one or more other points along
the axial trajectory; and guiding a second cutting tool with a
second guide at a second point along the axial trajectory
vertically spaced apart from a target surface when the second guide
may be positioned for use at the surgical site while permitting
movement of the second cutting tool away from the axial trajectory
at the one or more other points along the axial trajectory.
[0017] The first point may lie on the axial trajectory where the
axial trajectory intersects a target surface. The first cutting
tool may be the same as the second cutting tool. The second cutting
tool may have a larger diameter than the first cutting tool. The
method may include guiding a plurality of progressively larger
diameter drills with the second guide. The method may include
providing a plurality of guides with a respective plurality of
larger holes for at least one of the first point and the second
point along the axial trajectory. The target surface may be a
dental implant site. The target surface may be a surgical site. At
least one of the first cutting tool and the second cutting tool may
include one or more of a drill, a surgical drill, a rotary tool,
and a surgical hand tool. The first guide and the second guide may
be integrated into a single device for concurrent use. The method
may include supporting the single device with a support including
one or more of a bone support, a tooth support, and a soft tissue
support. The first guide and the second guide may be physically
separate devices. The first guide and the second guide may include
progressively larger holes and the first guide and the second guide
may be progressively applied to enforce the axial trajectory for
progressively larger tools. The method may include supporting one
of the physically separate devices with a support including one or
more of a bone support, a tooth support, and a soft tissue
support.
[0018] At least one of the first cutting tool and the second
cutting tool may include a drill with a drill stop. At least one of
the first guide and the second guide may include a window for
visual access to the surgical site when placed for use at the
surgical site. At least one of the first guide and the second guide
may include a window for physical access to the surgical site when
placed for use at the surgical site. The first guide may include
one or more visible alignment marks to assist a user in centering
the first cutting tool on the axial trajectory. The second guide
may include one or more visible alignment marks to assist a user in
centering the second cutting tool on the axial trajectory. At least
one of the first guide and the second guide may be formed of a
cuttable material. The method may include cutting at least one of
the first guide and the second guide to adjust the axial
trajectory. The first guide may include a hole for the first
cutting tool, and the method may include adding a sleeve to the
hole to protect against a cutting edge of the first cutting tool.
The second guide may include a hole for the second cutting tool,
and the method may include adding a sleeve to the hole to protect
against a cutting edge of the second cutting tool. At least one of
the first guide and the second guide may be formed of a clear
material.
[0019] In another aspect, a method disclosed herein includes
obtaining three-dimensional data from beneath a target surface of a
surgical site; determining an axial trajectory for an implant to be
placed in the surgical site based upon the three-dimensional data;
and fabricating a device, the device including: a surgical guide
formed of a hole in a layer that aligns a tool to the axial
trajectory when the surgical guide may be placed for use at the
surgical site; an interior space along the axial trajectory within
the device; a window in a side of the device for access to the
interior space; and a support to secure the surgical guide in
relation to the surgical site.
[0020] The three-dimensional data from beneath the target surface
may include non-surface, interior data from within one or more
dental structures. Access to the interior space may include
physical access. Access to the interior space may include visual
access. The layer may be a thin layer that permits movement of the
tool away from the axial trajectory at one or more points along the
axial trajectory. The interior space may be between the layer and
the target surface when the device may be placed for use at the
surgical site. The layer may be a thick layer that confines the
tool to the axial trajectory. The window may provide a view of the
axial trajectory where the axial trajectory intersects the target
surface when the device may be placed for use at the surgical site.
The window may provide a view of the axial trajectory where the
axial trajectory intersects the layer. The window may include a
transparent surface of the device. The axial trajectory may be a
trajectory of a surgical drill into a dental implant site. The
axial trajectory may be a trajectory of a surgical drill into the
surgical site. The target surface may include one or more of soft
tissue and bone. The target surface may include one or more of
gingiva and a jawbone. The surgical site may include a dental
implant site.
[0021] The hole may be shaped and sized to align an object
including one or more of a drill, a surgical drill, a rotary tool,
and a surgical hand tool to the axial trajectory. The support may
include a surface formed to dentition around the surgical site,
thereby providing tooth support for the surgical guide. The surface
may be formed to a full arch containing the surgical site. The
support may be shaped and sized to provide bone support for the
surgical guide. The support may include one or more bone attachment
points for securing the surgical guide to a jawbone, thereby
providing bone support for the surgical guide. The support may be
shaped and sized to provide soft tissue support for the surgical
guide. The support may be shaped and sized to provide gingival
support for the surgical guide. The support may be shaped and sized
to provide skin support for the surgical guide.
[0022] The layer may contact the target surface in an area
surrounding the hole when the surgical guide is placed for use at
the surgical site. The layer may be spaced apart from the target
surface in an area surrounding the hole when the surgical guide is
placed for use at the surgical site. The window may be positioned
between the layer and the target surface. The window may be
positioned between the layer and a second layer that abuts the
target surface. The interior space may be coextensive with the
hole. The interior space may include a volume between the layer and
the target surface that permits an insertion of the tool off-axis
from the axial trajectory. The surgical guide may include a second
hole in a second layer that aligns the tool to the axial trajectory
when the surgical guide may be placed for use at the surgical site.
Fabricating the surgical guide may include fabricating the surgical
guide from a cuttable material. The method may include modifying
the axial trajectory by enlarging the hole.
[0023] The surgical guide may include a plurality of holes in the
layer for a plurality of axial trajectories at different locations
in a dental arch. The method may include fabricating a plurality of
surgical guides, each including a progressively larger hole to
align one of a number of progressively larger diameter drills to
the axial trajectory. The method may include adding a sleeve to the
hole that protects the surgical guide against a cutting edge of the
tool. The sleeve may be formed of a material including one or more
of a steel, a titanium, a glass, a plastic, and an aluminum.
[0024] In another aspect, a device disclosed herein includes a
surgical guide, the surgical guide including a hole in a layer, the
hole positioned to align a tool to an axial trajectory at a first
point along the axial trajectory, and the hole including a tapered
wall that provides a diameter that varies along an axis of the
hole, wherein the diameter ranges between a narrowest section and a
widest section; and a support to secure the surgical guide in
relation to a location where the axial trajectory meets a target
surface of a surgical site.
[0025] The device may include a second hole in a second layer
vertically spaced apart from the first layer, the second hole
positioned to align the tool to the axial trajectory at a second
point along the axial trajectory. The target surface may include
one or more of soft tissue and bone. The target surface may include
one or more of gingiva and a jawbone. The surgical site may include
a dental implant site. The axial trajectory may be a trajectory of
a surgical drill into a surgical site. The axial trajectory may be
a trajectory of a surgical drill into a dental implant site. The
hole may be shaped and sized to align an object to the axial
trajectory including one or more of a drill, a surgical drill, a
rotary tool, and a surgical hand tool. The support may include a
surface formed to dentition around the surgical site, thereby
providing tooth support for the surgical guide. The support may
include a surface formed to bone around the surgical site, thereby
providing bone support for the surgical guide. The support may
include one or more bone attachment points for securing the device
to a jawbone. The support may include a surface formed to soft
tissue around the surgical site, thereby providing soft tissue
support for the surgical guide. The layer may be vertically spaced
apart from the target surface in an area surrounding the hole when
the device may be placed for use at the surgical site. The layer
may include one or more visible alignment marks to assist a user in
locating a center of the hole.
[0026] The device may include a window for visual inspection of the
target surface while the surgical guide may be in use. The device
may include a window for physical access to the surgical site when
the device may be placed for use. The device may be fabricated from
a cuttable material. The device may include a plurality of holes in
the layer for a plurality of axial trajectories. The hole may
include a sleeve that protects the surgical guide against a cutting
edge of the tool. The sleeve may be formed of a material including
one or more of a steel, a titanium, a glass, a plastic, and an
aluminum. The surgical guide and the support may be formed of a
clear material. The layer may have a thickness less than the
diameter of the hole at the widest section. The layer may have a
thickness less than the diameter of the hole at the narrowest
section. The layer may have a thickness greater than the diameter
of the hole at the narrowest section. The layer may have a
thickness greater than the diameter of the hole at the widest
section. The diameter of the hole at the widest section may be at
least ten percent greater than the diameter of the hole at the
narrowest section. The diameter of the hole at the widest section
may be at least twenty-five percent greater than the diameter of
the hole at the narrowest section. The widest section may be on a
top of the layer and the narrowest section may be on a bottom of
the layer. The narrowest section may be at a surface of the layer
proximal to the location where the axial trajectory meets the
target surface of the surgical site. The narrowest section may be
at a surface of the layer distal to the location where the axial
trajectory meets the target surface of the surgical site. The
narrowest section may be between a top surface and a bottom surface
of the layer.
BRIEF DESCRIPTION OF THE DRAWINGS
[0027] The foregoing and other objects, features and advantages of
the invention will be apparent from the following description of
particular embodiments thereof, as illustrated in the accompanying
drawings in which like reference characters refer to the same parts
throughout the different views. The drawings are not necessarily to
scale, emphasis instead being placed upon illustrating the
principles of the invention.
[0028] FIG. 1 shows a surgical drill guide for dental
applications.
[0029] FIG. 2 illustrates bone support for a surgical guide.
[0030] FIG. 3 illustrates soft tissue and bone support for a
surgical guide.
[0031] FIG. 4 shows a surgical guide.
[0032] FIG. 5 shows a surgical guide.
[0033] FIG. 6 shows a method for performing a dental implant
procedure.
[0034] FIG. 7 shows a two-layer surgical guide.
[0035] FIG. 8 is a cross-sectional view of a two-layer surgical
guide.
[0036] FIG. 9 is a cross-sectional view of a two-layer surgical
guide.
[0037] FIG. 10 shows a surgical guide with a window.
[0038] FIG. 11 shows a surgical guide with a window.
[0039] FIG. 12 is a cross-sectional view of a surgical guide.
[0040] FIG. 13 is a cross-sectional view of a surgical guide.
[0041] FIG. 14 shows alignment marks for a hole in a surgical
guide.
[0042] FIG. 15 shows a system for creating a surgical guide.
DETAILED DESCRIPTION
[0043] Described herein are devices and methods for enforcing an
axial trajectory during a drilling operation. In particular,
exemplary embodiments of the invention include devices and methods
for guiding a surgical drill along a predetermined axial trajectory
during a dental implant procedure. As used herein, the term "axial
trajectory" refers to a straight line defined by at least two
separate points that characterize an intended path (typically the
center of the path) for a drill into a site such as a surgical
site. The axial trajectory for a particular surgical operation may
be determined, for example, using planning software or the like
prior to the surgical operation based upon three-dimensional data
acquired from the surgical site. It will be understood that while
the following description depicts lower-jaw drill guides, one of
ordinary skill in the relevant art may readily adapt the surgical
guides and related procedures to an upper jaw, and all such
variations are intended to fall within the scope of this
disclosure.
[0044] FIG. 1 shows a device 100 including a surgical guide 101 and
a support 102. In general, the surgical guide 101, which may be a
surgical drill guide for use in dental procedures or the like, may
include one or more holes 110 to align a drill with an axial
trajectory 112. The support 102 may be fitted to the teeth 104,
soft tissue 106, and/or bone 108 in order to retain the surgical
guide 101 relatively immobile with respect to the bone 108 during a
drilling operation. It will be understood that while terms such as
"surgical guide" or "drill guide" are typically used in the art to
describe the entire device 100 depicted in FIG. 1, the following
description refers periodically to a "surgical guide" instead as
that portion of such a device 100 that physically retains a drill
or other tool or object along the axial trajectory 112 in order to
distinguish this functional portion from the support 102, which
operates to secure the surgical guide 101 (and the axial trajectory
112 defined by same) relative to a target location. Thus depending
on the context a "surgical guide" as used herein may refer
specifically to a portion of a device that has one or more holes
(or other guiding elements), or may refer generally to an entire
device that is used as a drill guide or the like.
[0045] The support 102 may be fabricated to conform to any features
within a patient's mouth including the teeth 104, soft tissue 106,
and bone 108. This design may be derived for example from a model
of a patient's dental arch or from three-dimensional digital scans
or other three-dimensional data from a surgical site. In general,
the support 102 secures the surgical guide 101 in relation to a
location where the axial trajectory 112 meets a target surface
113.
[0046] The support 102 may provide tooth support, soft tissue
support, and/or bone support. As depicted, the support 102 may
include a surface 116 (the interior surface of the device 100)
formed to dentition around a dental implant site, thus providing
tooth support. The surface 116 may be formed to a full arch
containing the dental implant site, or some portion thereof. The
support 102 may also or instead provide soft tissue support with
the surface 116. This may include skin support, gingival support,
or more generally any soft tissue support by which the surface 116
is formed to the skin, gingiva, gum, mucosa, and the like. The
support 102 may also, or instead, provide bone support, which may
in use involve supplemental surgical procedures such as cutting and
lifting a flap of the soft tissue 106 to expose the bone 108 so
that the surface 116 can be placed in direct contact with the bone
108, or using one or more screws or other attachments to secure the
support 102 directly to the bone 108. More generally, the support
102 may provide support to fix the surgical guide 101 relative to
the bone 108 using any or all of the above techniques, and the
support 102 may usefully cover more or less of the dentition and
surrounding tissue than depicted, all without departing from the
scope of this disclosure.
[0047] While not visible in FIG. 1, it will be appreciated that the
target surface 113 extends to a location beneath the surgical guide
101 where the axial trajectory 112 intersects the soft tissue 106
or bone 108 so that a drill or other tool may be directed into the
jaw at an appropriate location and orientation. As used herein, the
term "target surface" is generally intended to refer to an
exterior, two-dimensional surface of a surgical site that includes
a location where a drill, tool, or implant is intended to enter the
surgical site, unless a different meaning is specifically provided
or otherwise clear from the context. In general, the target surface
follows surface contours of a dental arch that is prepared for
surgery and includes a single point of intersection with the axial
trajectory 112. The target surface 113 may include any soft tissue
106 or bone 108 as described herein.
[0048] While the systems and methods described below are useful in
dental surgery, it will be appreciated that these systems and
methods may more generally be used at a surgical site, which as
used herein is intended to refer to a volume surrounding and
including a location where surgery will be performed. This may
include a dental implant site where a dental implant is to be
placed in a jawbone or more generally any site along the dental
arch or elsewhere that a drill or other cutting tool might usefully
be guided in a surgical procedure.
[0049] FIG. 2 illustrates bone support for a surgical guide. In a
bone supported guide 200, a flap of the soft tissue 202 may be cut
and lifted as illustrated in order to expose the bone 204
underlying the soft tissue 202. In other embodiments, a portion of
the gum may be cut away using a punch or similar device to expose
the underlying bone around the drill site. One or more screws 206
may also be used to secure the bone supported guide 200 to the bone
204. It will be appreciated that, while introduced in the context
of a prior art drill guide, bone support may also be used with the
drill guides described below.
[0050] FIG. 3 illustrates soft tissue and bone support for a
surgical guide. The guide 300 may be placed directly in contact
with soft tissue 302 such as skin or gums, and one or more screws
306 may be used to further secure the guide 300 to the underlying
bone 304. It will be appreciated that, while introduced in the
context of a prior art drill guide, bone and soft tissue support
may also be used with the drill guides described below.
[0051] Returning to FIG. 1, the teeth 104 (directly beneath the
surgical guide 101 and/or support structure 102 in FIG. 1) may be
any human or animal dentition. In a dental application, the soft
tissue 106 may, for example include gums, gingiva, mucosa, and/or
skin, as well as combinations of these. The bone 108 may include a
jawbone. It will be understood that the teeth 104, bone 108 and
soft tissue 106 are depicted in the generalized form of a dental
model, and that the shape of these features in vivo may vary
significantly from this abstract representation. In practice, while
the device 100 might be test-fitted to such a dental model, the
device 100 is intended for use in vivo where an opposing arch,
tongue, lips, and other anatomical features and the like are also
present.
[0052] One or more holes 110 may be provided within the surgical
guide 101 that are shaped, sized, and oriented to align a drill,
hand cutting tool, or other tool or item with the axial trajectory
112. Further, while the device 100 may be specifically designed and
used to guide a drill, it will be understood that any object may be
usefully aligned with the device 100 such as a grinding bit, a
drill, a surgical drill, a surgical hand tool (or any other
surgical tool), a dental implant screw, a healing abutment, an
implant, and so forth. It will be noted that in the prior art
device 100 of FIG. 1, the hole(s) 110 are relatively deep, and as a
result the elongated cylindrical interior shape of the hole(s) 110
fully constrains a drill of matched diameter (usually very slightly
smaller than the hole(s) 110) to the axial trajectory 112, and does
not permit excursions of such a drill positioned in the device 100
away from the axial trajectory 112 along the length of the drill.
Even with smaller drills, the hole(s) 110 may tend to bind a drill
that is misaligned to the axial trajectory 112 during use.
[0053] While three holes 110 are depicted, it will be understood
that the surgical guide 101 may include fewer or more holes. Thus
for example, the surgical guide 101 may include one hole, two
holes, three holes, four holes, or any other suitable number of
holes, such as for multiple implants that are planned for a patient
using the device 100. It will also be appreciated that each hole
110 may include a sleeve 114 therein that protects the surgical
guide 101 against a cutting edge of a drill or other tool. The
sleeve 114 may be formed of a steel, a titanium, a glass, a
plastic, an aluminum, or any other material or combination of
materials suitably hardened to resist cutting or abrasion from a
cutting tool such as a drill.
[0054] The axial trajectory 112 may be determined using any
suitable computerized or manual case planning tools. For example a
dental surgeon may use implant planning software or the like based
upon three-dimensional tomographic data or other topology
information to determine an appropriate axial trajectory to drill a
hole into which a dental implant is to be placed. This surgical
plan may be transferred to a patient by fabricating a device, such
as any of the devices described herein, that is fitted to a
patient's mouth and that includes one or more holes that enforce
the axial trajectory.
[0055] When placed for use at a surgical site in the patient's
mouth (e.g., aligned and fitted to gums, teeth, and so forth), the
device may be used to assist a surgeon in creating a properly
positioned and oriented hole for placement of the implant. It will
be understood that the devices herein are sometimes described in
terms of the context in which they are deployed, e.g., placed for
use at a surgical site. This may include references to the bone,
teeth, and/or soft tissue and so forth that position and support a
guide, as well as the target surface where a hole is to be made.
While this associated physical context may affect the shape or
configuration of a guide, these items are not to be construed as
features of the disclosed invention unless otherwise clearly stated
to the contrary.
[0056] As a significant disadvantage, a surgical drill must be
inserted into the device 100 of FIG. 1 on-axis, that is,
pre-aligned with the axial trajectory 112, which may prove
difficult in confined spaces such as in patients with limited mouth
opening and/or in the posterior portions of an arch where the teeth
or other anatomy of an opposing arch afford little maneuvering
room. In addition, a drill may bind if misaligned in a long tube,
even where the drill has a substantially smaller diameter than the
guide. As another disadvantage, the device 100 may obstruct a
surgeon's view of the location where a drill intersects the target
surface, which may prevent the surgeon from viewing drill depth or
other aspects of a procedure. Improved drill guides, and methods of
using same, are now discussed in greater detail.
[0057] FIG. 4 shows a surgical guide. In general, the device 400
includes a support 402 and a surgical guide 404, which may include
any of the supports and surgical guides described above, with
differences as noted in the following description.
[0058] The device 400 may be fabricated using any of a variety of
techniques, including casting or molding the device 400 from a
model of the patient's mouth. The device 400 may also or instead be
fabricated based upon three-dimensional data, along with any
suitable rapid prototyping system(s) including without limitation
three-dimensional printing, stereolithography, computerized milling
and so forth. More generally any computer-driven fabrication
technique may be employed including computerized milling,
machining, drilling, and so forth. A digital model of the device
400 may be manipulated in a computer environment before fabrication
in order to add holes, alignment marks, or other markings such as
patient identification data and so forth.
[0059] Three-dimensional data may take a variety of forms (e.g.,
surface, volumetric, etc.) and may be obtained from a variety of
imaging techniques. Thus for example, in various uses described
herein, three-dimensional data may be 602 obtained, e.g., using any
of a variety of three-dimensional surface scanning technologies
such as image-based, video-based, structured-light, time-of-flight,
or other techniques. Non-surface data may also be obtained, such as
interior data characterizing structures below the surface, such as
data obtained from CT scans, x-ray tomography, and so forth. In
general, as used herein, data beneath a surface will be understood
to refer to such interior, volumetric, or non-surface data (which
may of course extend up to and include a surface), without regard
to the relative orientation of the surface and the interior in
general three-dimensional space. It will further be appreciated
that surface data and interior data may be registered to provide a
digital model with both surface data and interior data. More
generally, any form of three-dimensional data that characterizes
the relevant surfaces and structures for the design and fabrication
of drill guides may be suitably adapted to use with the systems and
methods described herein. In addition, dental structures
characterized by such three-dimensional models may include any
anatomic structure associated with a drilling procedure including
without limitation teeth, jawbones, maxillary sinus, nerve canals,
and so forth.
[0060] In general, the support 402 secures the surgical guide 404
in relation to a location where an axial trajectory 406 meets a
target surface 408. The support 402 may include any of the supports
described above including a tooth support, a bone support, a soft
tissue support, or any combination of the foregoing. While the
axial trajectory 406 is depicted as substantially normal to the
target surface 408, it will be understood that the axial trajectory
406 may have any suitable orientation and position for forming a
desired hole in the bone 410 for a dental implant.
[0061] The surgical guide 404 may include one or more holes 412 in
a layer 420 to align a tool to the axial trajectory 406 at a first
point 416 along the axial trajectory 406 while permitting movement
of the tool away from the axial trajectory 406 at a second point
418 along the axial trajectory 406, as indicated generally by an
arrow that depicts a possible excursion from the axial trajectory
406 at the second point 418. In general, the surgical guide 404 is
formed of a layer 420 of any suitable material or combination of
materials. It will be noted in a comparison to the prior art
surgical guide 101 of FIG. 1 that the surgical guide 404 disclosed
herein uses a thin layer. The hole 412 in the thin-layer guide
serves to retain a drill or other device of corresponding diameter
(usually slightly smaller in diameter than the hole) in a position
centered on the axial trajectory 406 at the first point 416 without
constraining axial rotation of the drill at positions away from the
first point 416, such as the second point 418. As will be discussed
in greater detail below, a second guide may serve to define another
point along the axial trajectory 406, such as the second point 418
or any other point spaced away from the target surface 408, and may
be used in conjunction with the surgical guide 404 to impose a
fixed position and orientation on a drill corresponding to an axial
trajectory from a surgical plan. Thus the layer 420 should be
sufficiently thin to permit axial movement of a matched drill at
points away from the first point 416, while being sufficiently
thick to provide strength and rigidity that helps to retain a drill
bit centered on the first point 416 during a drilling
operation.
[0062] It should be clear from the foregoing that a specific
thickness of the layer 420 is not required to permit substantial
off-axis movement of a tool that is substantially matched (e.g.,
having a slightly smaller diameter) in size to the hole 412. For
example the layer 420 may have a thickness in an area about the
hole 412 that is less than a diameter of the hole 412, or less than
a radius of the hole 412 (e.g., a one millimeter diameter hole in a
0.5 millimeter layer), or significantly less than a radius of the
hole 412 (e.g., a two millimeter hole in a 0.5 millimeter layer).
This property of off-axis movement may also be characterized in
terms of the degree of off-axis maneuverability afforded to a tool
that is substantially matched to the hole 412 (that is, having the
same nominal diameter, although the tool necessarily has a slightly
smaller diameter if it is not intended to cut the surgical guide
404 during use). For example, the surgical guide 404 may permit a
five degree off-axis excursion of a one millimeter diameter drill
placed in a one millimeter diameter hole, a ten degree excursion of
a one millimeter diameter drill placed in a one millimeter diameter
hole, and so forth (generally without damaging or otherwise
compromising the guide). It will further be understood that a
thickness of the surgical guide 404 may be varied according to
other factors such as the type of material used to form the layer
420, the degree of flexibility desired for orientation of a drill
about the axial trajectory 406, whether the layer 420 is intended
to be cuttable for intra-operative modifications to the axial
trajectory 406, the type of drill or tool used, and so forth. All
such variations are intended to fall within this disclosure, and
may be readily distinguished from the surgical guides of the prior
art which purposefully and strictly constrain the position and
orientation of a matched drill bit along its entire length to the
axial trajectory 406.
[0063] As depicted in FIG. 4, the layer 420 may contact the target
surface 408 in an area such as the surface area, volume or other
space surrounding the hole(s) 412. This configuration may, for
example, be useful for positioning an initial pilot hole or the
like according to the axial trajectory 406. In other embodiments
described below, the layer 420 may be spaced apart from the target
surface in an area surrounding the hole, such as to impose the
second point 418 of the axial trajectory 406 onto a drill bit or
other tool with which the surgical guide 404 is used.
[0064] While a single axial trajectory 406 is depicted, it will be
understood that the surgical guide 404 may include a plurality of
holes 412 for a plurality of axial trajectories 406. The hole(s)
412 may be sized for a drill of a particular diameter, or the
hole(s) 412 may be sized for a thin, sharp instrument that can be
used to create a bleeding point or other mark at the first point
416 to assist a surgeon in creating an initial pilot hole or the
like. The surgical guide 404 may also or instead include a visible
marking such as an `x` or any other suitable marking(s) and/or
surface features to mechanically and/or visually guide a surgeon to
a correct starting location for a drill. It will be appreciated
that the bleeding point may also be established using a prior art
tube-type guide or any other technique, without departing from the
scope of this disclosure.
[0065] The first point 416 may be at a location where the axial
trajectory 406 intersects the target surface 408. This location
may, for example, include a dental implant site as generally
depicted in FIG. 4, and the axial trajectory 406 may be a
trajectory of a surgical drill into the dental implant site. More
generally, the location may be any surgical site, and the axial
trajectory 406 may be a trajectory of a surgical drill into the
surgical site. Still more generally, the principles disclosed
herein may be applied in any context, surgical or otherwise, where
constraints such as maneuvering room, visibility, and flexibility
can be usefully addressed with the methods and systems disclosed
herein.
[0066] In one aspect, the support 402 and/or the surgical guide 404
may be fabricated from a clear plastic or other transparent or
translucent material that permits a surgeon to view the target
surface 408 and/or surrounding areas during a procedure. The
support 402 and/or the surgical guide 404 may be formed of a
cuttable material to permit customization of the device 400, such
as according to a surgical plan that has been revised after
fabrication of the device 400. Where the device 400 is fabricated
from a cuttable material, the axial trajectory can be modified, for
example, by enlarging the hole with a drill or any other hand
cutting tool or powered cutting tool. In other embodiments, each
hole 412 may include a hardened ring of stainless steel or any
other cut-resistant, biocompatible material such as the materials
identified above to provide an abrasion-resistant sleeve. A variety
of cuttable, cut-resistant, biocompatible, and/or clear materials
are known in the art and may be suitably adapted to use with the
systems and methods disclosed herein.
[0067] FIG. 5 shows a device 500 including a support 502 and a
surgical guide 504. The support 502 and the surgical guide 504 may,
for example, be as shown and described with reference to FIG. 4,
with differences noted below.
[0068] A layer 506 of material that forms the surgical guide 504
may be spaced apart from a target surface 508 in an area 510 where
an axial trajectory 512 intersects the target surface 508, which
area 510 may include any surrounding surfaces and/or volume. The
layer 506 may be of any shape or size consistent with adequate
support of the surgical guide 504 in a manner to retain a drill or
other tool as described herein. In one aspect, the separation of
the layer 506 from the target surface 508 provides an interior
space 513 around the axial trajectory 512 including a working
volume that permits an insertion of a tool off-axis from the axial
trajectory 512. In addition, the layer 506 may be shaped to include
a window 514 with an opening for physical access to the space
between the layer 506 and the target surface 508. This window 514
may be used for access by a surgeon to the target surface 508 for
cleaning, inspection, irrigation, suction, material or tool
removal, or any other purpose. The window 514 may also or instead
provide an opening for visual inspection of the target surface 508
while the surgical guide 504 is in use (e.g., with a drill inserted
into one of the holes in the surgical guide 504). The window 514
may include an opening for visual inspection along some or all of
the axial trajectory 512 in the space between the target surface
508 and the layer 506 of material. It will be understood that the
window 514 or portions thereof may be formed of a clear material
that provides visual access into areas enclosed by the surgical
guide 504 and/or the support 502 without affording physical
access.
[0069] A hole 516 in the surgical guide 504 can serve to guide or
otherwise retain a tool (not shown) at a point above or otherwise
separated from the target surface 508. By using the device of FIG.
5 in combination with (e.g., sequentially with) the device of FIG.
4, the entire axial trajectory 512 of a surgical plan can be
enforced by using a first guide (such as the guide of FIG. 4) to
establish a point where the axial trajectory 512 intersects the
target surface 508 and using a second guide (such as the guide of
FIG. 5) to establish a second point along the axial trajectory 512.
By guiding a drill through the second guide into the drill hole
formed using the first guide, two points sufficient to establish
the axial trajectory 512 are imposed on a drill. Where a surgeon
wishes to make intra-operative modifications to the axial
trajectory 512, the first guide or the second guide may be modified
by cutting or otherwise enlarging or re-shaping the hole to shift
or re-orient the axial trajectory 512 at the first point, the
second point, or both. Similarly, a bleeding point may be used to
visually establish one point along the axial trajectory 512 on the
target surface 508, and the guide of FIG. 5 may be used to
establish another point along the axial trajectory 512. Either the
bleeding point or the hole may be modified intra-operatively as
desired by the surgeon.
[0070] While each hole 516 is depicted as round, any regular or
irregular, polygonal or curvilinear, or other shape, or any
combination of the foregoing, may also or instead be employed. Thus
for example, one or more of the holes 516 may be a square, a
hexagon, or other shape capable of retaining a substantially
cylindrical drilling tool such as a drill or the like along a path
defined by the axial trajectory 512. In another aspect, the holes
516 may be rectangular (or any other shape with a pair of long,
parallel sides), thus permitting movement of the axis of a tool in
a single plane, e.g., for off-axis insertion of a drill or for
manual, intraoperative adjustments to the axial trajectory 512. In
such embodiments, alignment marks may be provided to indicate a
desired orientation within the plane for the axial trajectory
512.
[0071] Numerous variations to the device 500 are possible. For
example, the device 500 may include any number of holes 516 for any
number of axial trajectories 512. In one aspect, each hole 516 may
have a funnel-shaped interior wall as described in greater detail
below. It will also be understood that the guide 504 and support
502 may have a variety of physical shapes and configurations
without departing from the scope of this disclosure. For example,
while the device 500 is depicted as resting on a distal or
posterior region of the target surface 508, this supporting
structure may be removed, such as to provide a greater working
volume for off-axis insertion of a drill into one of the holes 516
in the posterior region.
[0072] It will be further understood that a number of devices may
be provided having progressively larger hole sizes for
progressively larger drills, such as a narrow guide for a pilot
hole and a larger guide for a final hole, as well as any number of
intervening sizes consistent with a particular cutting operation.
In another aspect, a first guide with a small diameter (e.g., 0.7
millimeters for creation of a bleeding point or two millimeters for
creation of a pilot hole) may be provided that rests on the target
surface 508 where the axial trajectory 512 intersects the target
surface 508, and a second guide with a larger hole (e.g., 5.5
millimeters for a final, largest drill size) may be provided that
is spaced away from the target surface 508. A narrow diameter pilot
drill may be placed into the hole 516 in the second guide and
maneuvered into the pilot hole or bleeding point previously
created. This second guide may include visual markers to assist a
user in centering the pilot drill and a series of progressively
larger drills until a final hole diameter is achieved. In another
aspect, this may include two or more of the device 400 depicted in
FIG. 4 and two or more of the device 500 depicted in FIG. 5. Thus
in one aspect there is disclosed herein a plurality of devices each
including a hole positioned to align one of a number of
progressively larger diameter drills to a first point (which may be
a point on the target surface 508 or a point away from the target
surface 508) on the axial trajectory 512. In another aspect, the
plurality of devices may include holes to align drills to a number
of different points on the axial trajectory 512, and/or holes to
align drills to a number of different axial trajectories.
[0073] FIG. 6 shows a method for performing a dental implant
procedure using the surgical guides described herein. More
generally, the following method 600 realizes an axial trajectory of
a cutting process, which may be usefully employed in a dental
implant procedure, or any other surgical procedure that includes
translating an axial trajectory from a surgical plan to a patient.
Still more generally, the method 600 may be usefully employed in
any context where an axial trajectory is transposed from a model to
a physical object.
[0074] As shown in step 602, the method 600 may begin with data
acquisition. This may include acquisition of three-dimensional data
from beneath a surface of a surgical site, such as interior data
obtained from within one or more dental structures (e.g., teeth,
bone, soft tissue, etc.) through x-ray tomography or any other
suitable subsurface imaging technology. This may also or instead
include an acquisition of three-dimensional surface data obtained
using any suitable surface scanning technology. This may also or
instead include an acquisition of two-dimensional radiographs such
as orthopantomographs or periapicals. This may also include an
acquisition of three-dimensional information in the form of
physical models such as casts, molds, or impressions representative
of a dental implant site and surrounding dentition, tissue, and the
like.
[0075] Thus it will be understood that data acquisition may take a
variety of forms. Data acquisition may include acquisition of a
physical or analog model of a surgical site and/or teeth using,
e.g., conventional dental impressioning to create a physical model
and/or a cast for same. Data acquisition may also or instead
include a three-dimensional surface scan (using, e.g., video-based
techniques, structured light techniques, or any other suitable
three-dimensional surface scanning techniques) of a surgical site,
or of a physical model produced from a dental impression, or of
interior surfaces of a cast for a physical model. Data acquisition
may also or instead include an x-ray tomographic scan or surface
scan of an acrylic shell or other vacuum-formed or similar thin
layer cast of a physical model or surgical site. Data acquisition
may also include a capture of supplemental data such as
prescription information derived from a patient interview,
questionnaire, or the like, or information received from another
treating physician.
[0076] As shown in step 604, the method 600 may include case
planning to determine a course of action for a dental procedure. In
the case of a dental implant, this may include selecting a suitable
implant and determining an axial trajectory for a hole to receive
an implant, or the like. In general, positioning of the axial
trajectory is influenced by a variety of factors such as the
position, shape, and size of teeth, the avoidance of vital
structures, and the existence of adequate bone volume around the
hole. Depending on the procedure, the axial trajectory may be
realized using any number of drills (e.g., one to seven) of
increasing size from a smallest size for a pilot hole to a largest
size for the final hole that will receive the implant. Case
planning may also include an identification of other pre-surgical
treatment(s) in preparation for an implant. Case planning may
include the use of case planning software, including any of a
variety of commercially available software tools, to assist in
assessment of a surgical site and three-dimensional positioning and
orientation of an axial trajectory.
[0077] As shown in step 606, the method 600 may include fabricating
a number of surgical guides such as any of the guides described
herein. This may for example include interim steps such as a
creation of stereolithography fabrication files, milling machine
instructions, or the like to control a computerized fabrication
system including without limitation a stereolithography system, a
digital light processing system, a computer-controlled milling
machine, a three-dimensional printing system, or any other
computer-driven process such as a computer-controlled drill, lathe,
and so forth, as well as any combination of the foregoing. This may
also include manual fabrication based upon a physical model of a
surgical site. For example a material such as any pliable, curable
material may be placed on the physical model to capture a
complementary shape, and then cured to a sufficient hardness for
use as a support structure. Similarly, a sheet of material such as
plastic, which may be clear plastic, may be formed to the physical
model using vacuum forming or the like to produce the support
structure. In one aspect, fabrication may include a combination of
manual and automated steps. It will also be appreciated that
fabrication as contemplated herein may include any number of
interim fabrication and data acquisition steps, such as fabricating
an arch model using stereolithography (or any other suitable
technique for converting a digital model into a physical model),
and using the physical arch model for subsequent scanning or
fabrication steps such as preparing a shell that will be further
processed to fabricate a drill guide.
[0078] For example, a thin-layer guide such as various guides
described above may be fabricated from a plaster model or the like
to provide a form for a tooth support. The resulting cast may form
a shell that maps the contours of a surgical site in a physical
form. The shell may then be subjected to further computerized
processing to provide a surgical guide. For example, an axial
trajectory determined using three-dimensional data and case
planning software may be mapped to the manually fabricated support
structure or shell and used with a computer-controlled milling
machine or the like to accurately position and create a hole for a
surgical guide in the support. In another aspect, fabricating the
surgical guide(s) may include fabricating the shell or support with
an automated fabrication process and subsequently milling the
hole(s) with a manual or automated milling process or the like. In
general, creating a hole with a computer-controlled machine as
described herein may include any suitable computer-controlled
apparatus, such as a computer-controlled milling machine, a
computer-controlled drilling machine, a hole punch, a heated probe
(where the support is formed of a meltable plastic or similar
material), or any other machine that can be programmed or operated
with a computer to place a hole with a desired size in a desired
location.
[0079] As shown in step 608, the method 600 may include guiding a
first cutting tool with a first guide, such as any of the surgical
guides described herein. This may include guiding the first cutting
tool at a first point along the axial trajectory where the axial
trajectory intersects a target surface while permitting movement of
the first cutting tool away from the axial trajectory at one or
more other points along the axial trajectory. The first cutting
tool may, for example, be a surgical drill. In another aspect, the
first cutting tool may be a hand dental tool such as an osteotome
or other tool used to manually bore a hole for a dental implant. As
another example, the first cutting tool may be a sharp, pointed
hand tool used to create a bleeding point at a desired location.
More generally, the first cutting tool may include a drill, a
surgical drill, a rotary tool, a surgical hand tool, or any other
tool that might be guided along an axial trajectory. The target
surface may be a dental implant site, or more generally any
surgical site.
[0080] As shown in step 610, the method 600 may include guiding a
second cutting tool with a second guide such as any of the surgical
guides described herein. This may include guiding the second
cutting tool at a second point along the axial trajectory spaced
apart from the target surface while permitting movement of the
second cutting tool away from the axial trajectory at the one or
more other points along the axial trajectory, such as using one of
the thin-layer guides described above. The first cutting tool may
be the same as the second cutting tool, such as where guides are
sequentially applied to establish a point on the target surface and
then a point away from the target surface for a particular drill.
Or the first cutting tool and the second cutting tool may be
different cutting tools. For example, the second cutting tool may
have a larger diameter than the first cutting tool, such as with a
series of progressively larger cutting tools that result in a final
hole size suitable for a dental implant (or other implant anchor or
the like). In another aspect, the second guide may be used to guide
a plurality of progressively larger diameter drills. This may be
suitable where, for example, the first guide centers a pilot hole
or a bleeding point, and the hole in the second guide is over-sized
relative to the pilot hole or bleeding point, but may nonetheless
enforce the desired axial trajectory on a final drill matched to
the size of the hole in the second guide. In this example, a
dentist or surgeon may insert the smaller drill into the hole in
the second guide and maneuver the tip of the drill into the pilot
hole or bleeding point and center the smaller drill in the second
guide by eyesight, or with the aid of visual alignment marks or the
like on the second guide, aligning the drill with the axial
trajectory. In general, the second cutting tool may include a
drill, a surgical drill, a rotary tool, a surgical hand tool, or
any other tool that might be guided along an axial trajectory.
[0081] In one aspect, the first guide and the second guide may be
separate guides as generally discussed above. In another aspect,
the first guide and the second guide may be integrated into a
single physical device such as the two-layer device described
below.
[0082] As shown in step 612, the method 600 may optionally include
providing and using a plurality of guides with a respective
plurality of progressively larger holes for at least one of the
first point and the second point along the axial trajectory. Thus
any number of progressively larger drills may be guided with
suitably matched surgical guides.
[0083] As shown in step 614, after a hole of suitable diameter
centered on the axial trajectory has been prepared, a dental
implant may be inserted into the resulting hole. This may include,
for example, a self-tapping implant screw or any other suitable
implant.
[0084] As shown in step 616, any number of finishing steps may be
performed including steps performed immediately after placement and
steps performed at a later time such as steps relating to, e.g.,
aesthetics and fit of a crown, abutment, or other dental object
affixed to an implant.
[0085] As described above, the first cutting tool and the second
cutting tool may be the same or different, and may include any tool
usefully employed by a surgeon including without limitation a
drill, a surgical drill, a rotary tool, and a surgical hand tool.
The present invention is in no way limited by the type of surgical
tools or instruments employed. Additionally, as noted above, the
guides or guide layers employed may include any of the surgical
guides and/or supports described herein. More generally, the order
in which the steps of the present method are performed is purely
illustrative in nature, and the individual steps may be re-ordered,
removed, supplemented, modified, or otherwise altered without
departing from the scope of this disclosure.
[0086] For example, in one aspect, a bleeding point may be manually
positioned by a surgeon without the assistance of a guide, and the
"second guide" described above may be used with the manually
positioned bleeding point to align a drill to the axial trajectory.
Thus in one aspect there is disclosed herein a method that includes
creating a bleeding point at a first point on a target surface and
guiding a drill with a guide that includes a hole spaced away from
the target surface. The guide may include a thin layer guide with a
computer-positioned hole that is created using any of the
techniques described above.
[0087] By way of further example, a variety of combinations of
automated and manual steps, and/or combinations of computerized and
physical manipulations may be used consistent with the scope of
this disclosure. A physical impression may be used to create a
shell for a thin layer guide, or the thin layer guide may be
fabricated using stereolithography or any other suitable
computerized fabrication technique from a digital model that
includes the guide holes or a combination of these techniques may
be employed. In another aspect, a physical dental model (e.g., from
a physical impression) may be scanned to digitize surface data, and
this data may be combined with CT scan data to plan a trajectory
for a procedure, after which a digital model of a guide including
one or more guide holes may be directly fabricated using any
suitable computerized fabrication technique. Or a shell for a
physical thin layer guide may be obtained from a physical dental
model and digitized with any suitable scanning technique such as a
surface scanning technique or x-ray tomography to provide a digital
model of the shell, and holes may be placed within the shell in a
computer modeling environment. In this latter example, the
resulting digital drill guide model may be used to place holes in
the physical thin layer guide (with a computerized or manual
fabrication step), or the digital drill guide model may be used for
direct fabrication of an entire, final drill guide. In another
aspect, a three-dimensional surface scanning technique may be used
to obtain an initial, digital impression of the surgical site (and
surrounding dentition), which may in turn be used to fabricate a
physical model using any suitable computerized fabrication
technique. This physical model may be used in lieu of the physical
impression in any of the foregoing procedures. Still more
generally, the guides described herein may be fabricated using many
combinations of steps with physical and/or digital models, based
upon many combinations of source data (e.g., surface scans, CT
scans, etc.), and using a variety of computerized and/or manual
fabrication techniques. All such combinations that can be used to
obtain a physical realization of a guide as described herein are
intended to fall within the scope of this disclosure.
[0088] By way of further example, a variety of combinations of
automated and manual steps, and/or combinations of computerized and
physical manipulations may be used consistent with the scope of
this disclosure. A physical impression may be used to create a
shell for a thin layer guide, or the thin layer guide may be
fabricated using stereolithography or any other suitable
computerized fabrication technique from a digital model that
includes the guide holes, or a combination of these techniques may
be employed. In another aspect, a physical dental model (e.g., from
a physical impression) may be scanned to digitize surface data, and
this data may be combined with CT scan data to plan a trajectory
for a procedure, after which a digital model of a guide including
one or more guide holes may be directly fabricated using any
suitable computerized fabrication technique. In another aspect, a
shell may be obtained from a physical dental model, and the shell
may be digitized using any suitable three-dimensional scanning
technique such as a three-dimensional surface scan or x-ray
tomography to provide a digital model of the shell, and holes may
be placed within the digital model of the shell in a computer
modeling environment to provide a digital drill guide model. A
physical drill guide may then be fabricated from the digital drill
guide model using stereolithography or any other suitable rapid
prototyping or fabrication technique. The digital drill guide model
may also or instead by used to control an automated drilling
machine to place holes in the shell, thus converting the shell into
a thin layer guide as described above.
[0089] In another aspect, a three-dimensional surface scanning
technique may be used to obtain an initial, digital impression of
the surgical site (and/or surrounding dentition), which may in turn
be used to fabricate a physical model using any suitable
computerized fabrication technique. This physical model may be used
in lieu of the physical impression in any of the foregoing
procedures. Still more generally, the guides described herein may
be fabricated using many combinations of steps with physical and/or
digital models, based upon many combinations of source data (e.g.,
surface scans, CT scans, etc.), and using a variety of computerized
and/or manual fabrication techniques. All such combinations that
can be used to obtain a physical realization of a guide as
described herein are intended to fall within the scope of this
disclosure.
[0090] More generally, numerous methods may be employed for
fabricating surgical guides as described herein. By way of further
illustrative example, and not by way of limitation, a number of
additional, specific methods are now described. In one embodiment,
three-dimensional data may be obtained from a patient's dental arch
with a physical dental impression, which may in turn be used to
fabricate a physical model of the arch. An acrylic sheet or the
like may then be formed onto the physical model to obtain a shell.
The shell may then be used to fabricate a radiographic stent that
includes a radiopaque marker of the future tooth position and one
or more fiduciary markers (e.g., three fiduciary markers).
Three-dimensional x-ray tomography data may then be obtained
directly from the patient while the patient is wearing the
radiographic stent (e.g., the shell with the fiduciary markers).
Three-dimensional x-ray tomography data may also be obtained from
the radiographic stent alone (e.g., without the patient's
dentition) to provide source data for the drill guide. Implant
planning software may then be used to determine an implant
trajectory to provide implant data, and the implant data may be
combined with the three-dimensional data from the radiographic
stent alone to provide a digital model. The drill guide may then be
fabricated from this three-dimensional data set (the digital model
of the drill guide), with any suitable modifications, adaptations,
or other processing for output to a stereolithography system or
stereolithography design environment. In the stereolithography
design environment, which may be conventional stereolithography
software or software customized for designing and fabricating drill
guides as described herein, implant trajectories in the form of
guide holes may be imposed on the digital model based open the
implant trajectories. The shell may also be further modified to
remove or add to surfaces thereof, such as to provide windows,
alignment marks, and so forth, or to remove portions of the shell
that are not required for support of the guide or otherwise not
desired. The resulting digital model, with any modifications as
described above, may then be fabricated using stereolithography or
any other suitable fabrication technique.
[0091] In another aspect, an initial digital model of a patient's
dental arch may be obtained directly from the patient using any
suitable three-dimensional surface scanning technique such as
video-based scanning, structured light scanning, and so forth. A
shell may be created from the initial digital model within a
computer design environment, and used to fabricate a shell
corresponding to the patient's dental arch with, e.g.,
stereolithography. The shell may then be used to create a
radiographic stent and the method may proceed as described
above.
[0092] In another aspect, the drill guide may be more generally
hand-tooled. For example, three-dimensional surface data may be
obtained from a patient's dental arch with a physical dental
impression, which may be used in turn to fabricate a physical
dental model using known techniques. A shell may be vacuum formed
to the physical dental model, and the shell may be used to
fabricate a radiographic stent as described above.
Three-dimensional data may then be captured of a patient wearing
the radiographic stent, and the resulting data set may be used
within implant planning software to determine an appropriate
implant trajectory. The coordinates that define the implant
trajectory may be physically transferred to the shell using any
suitable technique, and one or more holes may be manually drilled
or otherwise created in the shell to provide a drill guide.
[0093] As previously noted, these specific examples are not
intended to limit the generality of the invention. Numerous other
variations and adaptations to the foregoing are possible, and all
such variations that are apparent to one of ordinary skill in the
art are intended to fall within the scope of this disclosure.
[0094] It will also readily be appreciated that a kit may be
provided for a surgical procedure according to any of the
foregoing. The kit may, for example, include one or more of the
guides described above, such as a number of guides with
progressively larger holes for an axial trajectory. The kit may
also include a corresponding collection of drills, such as
disposable drills, or the holes may be sized for a standard dental
or surgical drill set. The kit may also or instead include a number
of drill stops to achieve a predetermined drill depth for a
particular procedure, or drill stops for a surgeon to variably
control depth. In another aspect, the corresponding collection of
drills may be fabricated to include a drill stop, such as by
manufacturing drill bits with varying diameter sections. The kit
may also or instead include a variety of related components, such
as written instructions for a procedure, computerized instructions
for a procedure (on a compact disk or other storage medium),
sterilization materials, dental models, implant screws, and so
forth. The kit, or portions thereof, may be packaged in a sterile
packaging. More generally, any assembly and packaging of components
and materials to accompany the drill guides described herein may
usefully be provided as a kit for dental or other surgical use.
[0095] FIG. 7 shows a two-layer surgical guide. As depicted, a
device 700, which may include some or all of the features of any of
the devices described herein, may include two or more separate
layers integrated into a single guide. More specifically, the
device 700 may include a first hole 702 in a first layer 704
positioned to align a tool or the like to an axial trajectory at a
first point along the axial trajectory and a second hole 706 in a
second layer 708 spaced apart from the first layer, the second hole
708 positioned to align the tool to the axial trajectory at a
second point along the axial trajectory, all as generally discussed
above. More specifically, the first layer 704 may be vertically
spaced apart from the second layer 708 along the axial trajectory
so that the first hole 702 and the second hole 706 can fully define
the axial trajectory as generally described herein. Any number of
additional holes for additional axial trajectories may also be
included. The device 700 may include a support 710, such as any of
the supports described above, to secure the surgical guide in
relation to a location where the axial trajectory meets a target
surface of a surgical site. As depicted, the first layer 704 may be
attached to the support 710 on a single end thereof to provide full
physical and visual access to the surgical site and surrounding
areas. In another aspect, a second end of the first layer 704 may
include a further support structure attached to the second layer,
such as along a rear edge of the layers, for additional structure
support and rigidity. In another aspect, the device 700 may include
side walls between the first layer 704 and the second layer 708
fully or partially enclosing a space between the two layers. More
generally, a variety of supporting configurations and structures
may be included in the device 700, and all such variations are
intended to fall within the scope of this disclosure.
[0096] The first hole 702 may have the same diameter as the second
hole 706. In other embodiments, the second hole 706 may have a
smaller diameter than the first hole 702 (or alternatively stated,
the first hole 702 may have a larger diameter than the second hole
706) so that, for example, a drill stop or the like may be used
with a drill, where the drill stop is sized to fit through the
first hole 702 but not through the second hole 706. The first layer
704 and the second layer 708 may be sufficiently spaced apart to
provide a space for an insertion of a tool into the first hole 702
off-axis from the axial trajectory.
[0097] In one aspect, the guide may be fabricated using two
separate physical models of the surgical site. For example a first
model may be obtained with tooth or teeth that are to be replaced
by an implant-supported crown. A layer formed on this first model
may provide a layer away from the target surface to define a first
point along the axial trajectory. A second model may be obtained
with the tooth (or teeth) removed so that a layer formed on this
model rests directly against the target surface of the surgical
site. The first layer may then be molded onto or otherwise attached
to the second layer in various support areas to provide a one
piece, two layer guide. In another aspect, the entire device 700
may be fabricated from a computerized model or the like as
generally discussed above.
[0098] FIG. 8 is a cross-sectional view of a two-layer surgical
guide. The device 800 may include any of the devices or features
described herein. As shown, the device 800 may include a first
guide 802 formed by a first hole 804 in a first layer 806 and a
second guide 808 formed by a second hole 810 in a second layer 812
which may include any of the guides, holes, and layers described
above. The first guide 802 and the second guide 808 may be
integrated into a single device to provide a full spatial
definition for an axial trajectory 816 for a tool 818. Thus for
example, the first guide 802 may align the tool 818 at a point away
from a target surface 814 while the second guide 808 may align the
tool 818 where the axial trajectory 816 meets the target surface
814.
[0099] This arrangement may advantageously reduce the number of
separate devices required for a surgical procedure. For example,
the device 800 may permit an off-axis insertion of the tool 818
along a second axis 820 as depicted, thus decreasing the intraoral
clearance required to insert the tool 818 into the device 800. The
space between the first layer 806 and the second layer 812 may also
be accessible through a window or the like to provide physical
and/or visual access to the surgical site and/or the axial
trajectory 816. In general, the device 800 may be formed to rest
upon a target surface 814 and provide tooth support, soft tissue
support, and/or bone support as generally discussed above. It will
be noted that the device 800 is depicted with side walls for
support of the first guide 802 that might run along a dental arch,
while the device 700 of FIG. 7 provides end support for an upper
guide. In general, side walls, end walls, or any other supporting
structure(s), as well as combinations of these, may also or instead
be employed to secure a guide in a desired location away from a
target surface, and all such variations are intended to fall within
the scope of this disclosure. It will further be appreciated that,
while two side walls are depicted in the cross-sectional view of
FIG. 8, a cross section of the guide may include a window or
opening on either side or both sides, as shown for example in the
figures above. Thus while the first hole 804 and the second hole
810 are generally fixed relative to one another in a two-layer
guide, there is no requirement of any particular shape or
arrangement of supporting structure(s) used to maintain this
spatial relationship unless otherwise explicitly stated to the
contrary.
[0100] Numerous variations will be readily appreciated. In one
aspect, the device 800 may include any number of additional layers,
each providing a guide at a different distance from the target
surface 814. In another aspect, one or more of the plurality of
guides may be formed of a cuttable material while one or more other
ones of the plurality of guides may be formed of a cut-resistant
material, or include a sleeve or the like to resist cutting. Where
a cuttable material is used, the guide(s) may be modified before or
during use by cutting or otherwise modifying the hole(s)
therein.
[0101] FIG. 9 is a cross-sectional view of a two-layer surgical
guide. The device 900 may be any of the surgical devices described
above, such as the device 800 of FIG. 8. As shown in FIG. 9, after
a tool 902 is inserted into a first hole of the device 900 (either
on-axis or off-axis), a tip of the tool 902 may be directed toward
the second hole, thus bringing the tool into alignment with a
desired axial trajectory.
[0102] It will be appreciated from the foregoing that a window may
be usefully incorporated into a surgical guide for visual and/or
physical access to a surgical site. Using a thin-layer construction
as described, for example, with reference to FIG. 5, a window may
be formed directly in the surgical guide (or the surrounding
support) from an opening between the layer and the target surface,
or for a two-layer guide, between a first layer and a second layer.
For physical access, the window may include a physical opening in
the device. For visual access, a clear or transparent region of
material may also or instead be used. In another aspect, the entire
device 900 may be fabricated of a clear plastic or other
transparent material. The window may provide a view of the axial
trajectory where the axial trajectory intersects the layer, or
anywhere else between the layer and the target surface, and may
generally provide for visual access or physical access to the
surgical site.
[0103] FIG. 10 shows a surgical guide with a window. In general, a
device 1000 may include a surgical guide and a support as described
above. The device 1000 may also include a window 1002 bounded, for
example, on four sides by the walls of the surgical guide. The
window 1002 may provide a view of the axial trajectory where the
axial trajectory intersects the target surface. The window 1002 may
also or instead provide a view of any other portions of the axial
trajectory, or a drill or other tool inserted into the surgical
guide and traveling along the axial trajectory. The window 1002 may
be formed with a transparent material in the surgical guide, or the
window 1002 may include a physical opening in the surgical guide or
the support that provides a view of the space surrounding the axial
trajectory as well as physical access to the space. More generally,
the window may include any structures and/or materials that provide
visual and/or physical access to an interior space 1004 of the
device 1000. The interior space 1004 may be coextensive with a hole
used to guide a drill, or the interior space 1004 may include
additional interior volume(s) of the device 1000, such as regions
that accommodate off-axis insertion of a tool as generally
discussed above.
[0104] FIG. 11 depicts another embodiment of a window 1100 in a
surgical guide 1102. As shown in FIG. 11, the window 1100 may be
formed from a slit or other opening bounded on two substantially
vertical sides by the walls of the surgical guide 1102 (or
support). This window 1100 may proceed from a top to a bottom of
the surgical guide 1102 or along any other length of the walls. In
one aspect, the window 1100 may reach at least to the target
surface in order to provide visual inspection of a drill or other
tool as it contacts the target surface.
[0105] FIG. 12 is a cross-sectional view of a surgical guide. It
will be noted that some of the surgical guides described above are
designed to guide a tool or the like at a first point along an
axial trajectory while permitting excursions of the tool away from
the axial trajectory at other points along the axial trajectory.
This feature may be achieved using a thin layer as discussed
generally above. In another aspect, this feature may be achieved
using a relatively thicker guide (e.g., of a thickness used in
prior art drill guides) with a funnel-shaped or similar geometry
for a hole in the guide 1200. This geometry may confine a tool (not
shown) at one point along the axial trajectory 1202, while
permitting excursions such as off-axis insertion or use, at other
points. For example, as depicted in FIG. 12, a tool inserted into
the guide 1200 may be confined at a point 1203 away from a target
surface 1204, but permitted to move away from the axial trajectory
at other locations, such as positions closer to (or farther from)
the target surface, or more generally to move away from the axial
trajectory within a space 1206 within the guide 1200. Thus in one
aspect a surgical guide disclosed herein may include a hole that is
tapered into a funnel shape. The guide may be thicker than the
diameter of the funnel at its narrow end 1208 or, using a different
benchmark, thicker than a diameter of a tool matched to the guide
1200. It will be understood that while a linear funnel shape is
depicted, any similar shape, such as an arc, a parabola, or any
other regular or irregular wall profile that joins a wider hole on
one side of the surgical guide to a narrower hole on an opposing
side (e.g., a drill entry side and a drill exit side or the like)
may be similarly employed without departing from the scope of this
disclosure.
[0106] FIG. 13 is a cross-sectional view of a surgical guide. As
with FIG. 12 above, the surgical guide 1300 of FIG. 13 guides a
tool at one point along an axial trajectory while permitting
movement of the tool at other points along the axial trajectory.
More specifically with reference to FIG. 13, the surgical guide
1300 guides a tool of matched diameter where an axial trajectory
1302 intersects a target surface 1304, while permitting excursions
of the tool off the axial trajectory 1302 away from the target
surface 1304. Numerous similar arrangements will be readily
appreciated and are intended to fall within the scope of this
disclosure, such as any cross-sectional profile that confines a
tool to an axial trajectory at one or more points along the axial
trajectory while permitting off-axis movement at other points along
the axial trajectory. In other embodiments, a narrowest portion of
the hole may be between a top and bottom opening of the surgical
guide. So for example, the hole may be wide at a top surface, taper
to a narrower diameter in an interior portion of the guide, and
then widen again to a relatively wider opening at a bottom surface.
Still more generally, any profile for the taper or interior shape
of the hole consistent with the uses of a drill guide described
herein may be suitably incorporated into the device without
departing from the scope of this disclosure.
[0107] The funnel shape may also be usefully incorporated into a
thin layer guide, such as to steer a tool into a hole or to narrow
a layer at the hole to provide greater freedom of off-axis movement
for a matched-diameter tool inserted therein. In addition, while
the holes described herein may useful employ a linear taper to
provide a funnel shape as generally shown and described above, it
will be understood that other tapers may also or instead be
employed, such as curvilinear tapers or compound tapers that
variously increase and decrease as the hole is traversed from a top
surface of the layer (e.g., away from the target surface) or a
bottom surface (e.g., adjacent to the target surface). Thus the
hole may more generally include a tapered wall with a diameter that
varies along an axis passing through the hole. The diameter may,
for example, vary from a widest diameter on top to a narrowest
diameter on the bottom (as in FIG. 13), or the diameter may range
from a narrowest diameter on the top to a widest diameter on the
bottom (as in FIG. 12). The narrowest diameter may instead be
between the top and bottom surfaces of the layer to provide a
dual-funnel shape. In another aspect, the narrowest section may
extend from within the hole to a bottom surface of the guide. This
configuration may be employed in a relatively thick tube guide or
the like to accommodate off-axis insertion in a top, open funnel
portion of the guide, while providing longer side walls to axially
constrain a drill in a lower, cylindrical portion of the guide.
Thus more generally a variety of shapes for the hole may be
provided that vary from a narrowest diameter section (to guide a
drill) and wider diameter sections (to accommodate off-axis
movement of the drill when the guide is in use), and all such
variations are intended to fall within the scope of this
disclosure.
[0108] In this context, the "shape" refers to the cross-sectional,
vertical profile as depicted in FIGS. 12 & 13. Each hole also
has a z-axis shape, e.g., a cross-sectional, horizontal profile, as
depicted for example in FIG. 14. As discussed above, this latter
shape may be any closed, two-dimensional shape, and it should be
understood that the horizontal profile may vary as the hole is
traversed along an axis passing through the hole from surface to
surface of the guide. Thus for example, the hole may have an
elliptical or elongated shape on the top surface to accommodate
off-axis insertion of a drill, and may converge on a circular shape
at a bottom surface of the guide (where the guide contacts a target
surface) to accurately position a drill on the target surface.
[0109] In one aspect, the layer may have a thickness less than the
diameter at the narrowest section. The layer may instead have a
thickness greater than the diameter at the narrowest section. The
layer may also or instead have a thickness greater or less than the
diameter at the widest section. The diameter at the widest section
may be at least ten percent greater than the diameter at the
narrowest section, twenty five percent greater than the diameter at
the narrowest section, fifty percent greater than the varying
diameter at the narrowest section, or any other ratio suitable for
use as generally described herein. The widest section may be on a
top layer of the guide and the narrowest section may be on the
bottom layer of the guide. Alternatively stated, the narrowest
section may be at a surface of the guide proximal to a location
where an axial trajectory meets a target surface of a surgical
site. Or the narrowest section may be at a surface of the guide
distal to the location where the axial trajectory meets the target
surface of the surgical site. In other embodiments, the narrowest
section may be between a top surface and a bottom surface of a
layer of the guide, such as with the compound profiles discussed
above.
[0110] The surgical guide 1300 may also include alignment marks
(not shown), such as the alignment marks described below, to assist
a user in aligning a tool to a desired trajectory.
[0111] FIG. 14 shows alignment marks for a hole in a surgical
guide. A device 1400 may include a surface 1402, which may be a top
or visible surface that can be viewed by a user of the surgical
guide during use. The device 1400 may include a hole 1404 that
serves as a surgical guide as generally described above. In
addition, the device may include one or more visible alignment
marks 1406 to assist a user in locating a center of the hole 1404
during use, or otherwise assist a user in centering a tool such as
a cutting tool on the axial trajectory. While depicted in a
crosshair pattern, it will be appreciated that more or fewer marks
may be provided such as a grid or other regular pattern of lines or
other shapes. The visible alignment marks 1406 may include raised
or lowered (e.g., three-dimensional) surface features and/or
colored or other visual markings rendered in ink, or any other
suitable markings, surface treatment or the like that are visible
to a user. While a single layer is depicted, it will be further
understood that the visible alignment marks 1406 may be provided on
one or more layers of a multi-layer surgical guide, or any of the
other guide devices described herein.
[0112] FIG. 15 shows a system for creating a surgical guide. The
above methods for fabricating guides may in general be realized
using a system 1500 with a variety of components. For example, the
system 1500 may include a data acquisition system 1502, a
processing system 1504, and a computerized fabrication system
1506.
[0113] The system 1500 may optionally include a data acquisition
system 1502. The data acquisition system 1502 may, for example,
include any of the data acquisition systems described above. This
may include three-dimensional scanning systems for obtaining
surface data from dentition and surrounding dental structures, or
this may include computerized tomography systems for capturing
volumetric data and/or subsurface structural data (e.g., from
beneath the target surface of a surgical site) that may be usefully
employed in the methods described herein. The data acquisition
system 1502 may also or instead, include a physical interface such
as a keyboard and mouse for manual entry of information concerning
a patient, a guide, a surgical plan, and so forth.
[0114] The system 1500 may optionally include a processing system
1504 such as a computer or other suitable processor or processing
circuitry for performing functions associated with the fabrication
of a surgical guide. This may include, for example a computer
executing case planning software or providing other tools to assist
a clinician or lab technician in receiving data, planning a
surgical procedure, and specifying a drill guide for the surgical
procedure.
[0115] The system 1500 may optionally include a computerized
fabrication system 1506. This may be any computer-controlled
fabrication system including rapid prototyping systems using, e.g.,
stereo-lithography, three-dimensional printing, computerized
milling, and so forth, or any other computer-controlled machine or
combination of machines described herein. It will also be
appreciated from the methods described above, that many steps in
the methods described above may also, or instead, include manual
procedures such as the creation of vacuum-formed molds from dental
models and so forth.
[0116] It will be appreciated that many of the above systems,
devices, methods, processes, and the like may be realized in
hardware, software, or any combination of these suitable for the
control, data acquisition, and data processing described herein.
This includes realization in one or more microprocessors,
microcontrollers, embedded microcontrollers, programmable digital
signal processors or other programmable devices or processing
circuitry, along with internal and/or external memory. This may
also, or instead, include one or more application specific
integrated circuits, programmable gate arrays, programmable array
logic components, or any other device or devices that may be
configured to process electronic signals. It will further be
appreciated that a realization of the processes or devices
described above may include computer-executable code created using
a structured programming language such as C, an object oriented
programming language such as C++, or any other high-level or
low-level programming language (including assembly languages,
hardware description languages, and database programming languages
and technologies) that may be stored, compiled or interpreted to
run on one of the above devices, as well as heterogeneous
combinations of processors, processor architectures, or
combinations of different hardware and software. At the same time,
processing may be distributed across devices such as the various
systems described above, or all of the functionality may be
integrated into a dedicated, standalone device. All such
permutations and combinations are intended to fall within the scope
of the present disclosure.
[0117] In other embodiments, disclosed herein are computer program
products comprising computer-executable code or computer-usable
code that, when executing on one or more computing devices (such as
the devices/systems described above), performs any and/or all of
the steps described above. The code may be stored in a computer
memory, which may be a memory from which the program executes (such
as random access memory associated with a processor), or a storage
device such as a disk drive, flash memory or any other optical,
electromagnetic, magnetic, infrared or other device or combination
of devices. In another aspect, any of the processes described above
may be embodied in any suitable transmission or propagation medium
carrying the computer-executable code described above and/or any
inputs or outputs from same.
[0118] It will be appreciated that the methods and systems
described above are set forth by way of example and not of
limitation. Numerous variations, additions, omissions, and other
modifications will be apparent to one of ordinary skill in the art.
Thus, for example, while dental implant procedures are clearly
contemplated, this disclosure is not limited to oral surgery, but
may facilitate any osteotomy, bone surgery, bone replacement, or
other surgical procedure requiring drilling into bone or hard
tissue, or more generally any procedure involving alignment of a
tool to a desired trajectory. In addition, the order or
presentation of method steps in the description and drawings above
is not intended to require this order of performing the recited
steps unless a particular order is expressly required or otherwise
clear from the context.
[0119] While particular embodiments of the present invention have
been shown and described, it will be apparent to those skilled in
the art that various changes and modifications in form and details
may be made therein without departing from the spirit and scope of
the invention as defined by the following claims. The claims that
follow are intended to include all such variations and
modifications that might fall within their scope, and should be
interpreted in the broadest sense allowable by law.
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