U.S. patent application number 10/543034 was filed with the patent office on 2006-10-26 for dental tool guides.
This patent application is currently assigned to TACTILE TECHNOLOGIES LLC. Invention is credited to Opher Kinrot, Uriel Weinstein, Yuval Yohai.
Application Number | 20060240378 10/543034 |
Document ID | / |
Family ID | 32735523 |
Filed Date | 2006-10-26 |
United States Patent
Application |
20060240378 |
Kind Code |
A1 |
Weinstein; Uriel ; et
al. |
October 26, 2006 |
Dental tool guides
Abstract
A method of dental registration, comprising, rigidly coupling a
base element to a maxillofacial area; inserting an object
comprising at least one of a tool and a tool guide into a mouth in
said maxillofacial area; and determining a position of said object
relative to said rigid element without a reference element outside
of said mouth.
Inventors: |
Weinstein; Uriel;
(Mazkeret-Batya, IL) ; Yohai; Yuval; (Rehovot,
IL) ; Kinrot; Opher; (Raanana, IL) |
Correspondence
Address: |
WOLF, BLOCK, SCHORR & SOLIS-COHEN LLP
250 PARK AVENUE
NEW YORK
NY
10177
US
|
Assignee: |
TACTILE TECHNOLOGIES LLC
LAS VEGAS
NV
|
Family ID: |
32735523 |
Appl. No.: |
10/543034 |
Filed: |
January 23, 2004 |
PCT Filed: |
January 23, 2004 |
PCT NO: |
PCT/IL04/00069 |
371 Date: |
April 20, 2006 |
Current U.S.
Class: |
433/76 ;
433/72 |
Current CPC
Class: |
A61B 5/1077 20130101;
A61B 2090/3925 20160201; A61B 5/4504 20130101; A61B 5/407 20130101;
A61B 90/06 20160201; A61B 2090/3937 20160201; A61C 1/084 20130101;
A61C 19/04 20130101; A61B 2562/17 20170801; A61B 2090/061 20160201;
A61B 17/17 20130101; A61B 2562/046 20130101; A61B 17/176 20130101;
A61B 90/39 20160201; A61B 5/6878 20130101; A61C 9/0046 20130101;
A61B 5/6862 20130101; A61B 5/103 20130101; A61B 2090/063 20160201;
A61B 90/11 20160201; A61B 2090/033 20160201 |
Class at
Publication: |
433/076 ;
433/072 |
International
Class: |
A61C 3/02 20060101
A61C003/02 |
Foreign Application Data
Date |
Code |
Application Number |
Jan 22, 2003 |
US |
10/350,288 |
Claims
1. A method of dental registration, comprising: rigidly coupling a
base element to a maxillofacial area; inserting an object
comprising at least one of a tool and a tool guide into a mouth in
said maxillofacial area; and determining a position of said object
relative to said rigid element without a reference element outside
of said mouth.
2. A method according to claim 1, wherein said base element
comprises a rigid element.
3. A method according to claim 1, comprising acquiring a 3D
radiological image of at least a part of said maxillofacial
area.
4. A method according to claim 3, comprising acquiring a
non-volumetric image of at least a part of said dental area
including at least a part of said base element.
5. A method according to claim 4, comprising: identifying at least
one registration mark of said rigid element on said non-volumetric
image; and registering said image to said 3D image, thereby
registering said registration mark to said area.
6. A method according to claim 1, comprising: acquiring a first
image of at least a part of said maxillofacial area; acquiring a
non-volumetric image of least a part of said dental area including
at least a part of said base element; identifying at least one
registration mark of said rigid element on said non-volumetric
image; and registering said image to said first image, thereby
registering said registration mark to said area.
7. A method according to claim 6, wherein said first image
comprises a surface image obtained using a plurality of measurable
pins which penetrate gum tissue to bone tissue.
8. A method according to claim 6, wherein said non-volumetric image
comprises a 2D transmission image.
9. A method according to claim 5, wherein determining comprises
setting a desired position, and comprising selecting a desired
relative position.
10. A method according to claim 5, wherein determining comprises
measuring an existing position.
11. A method according to claim 10, wherein determining comprises
adjusting said object to a new position responsive to said measured
position.
12. A method according to claim 5, wherein determining comprises
aiming said tool using said position, at said maxillofacial
area.
13. A method according to claim 5, wherein rigidly coupling
comprises inserting at least one pin into gum tissue of said
maxillofacial area.
14. A method according to claim 5, wherein rigidly coupling
comprises coupling using a clamp.
15. A method according to claim 5, wherein rigidly coupling
comprises releasing said base element to elastically engage said
maxillofacial area.
16. A method according to claim 5, wherein rigidly coupling
comprises attaching using at least one screw.
17. A method according to claim 5, wherein rigidly coupling
comprises attaching to a single portion of said maxillofacial
area.
18. A method according to claim 5, wherein rigidly coupling
comprises attaching said rigid element to be adjacent to at least
35% of a jawbone of said maxillofacial area.
19. A method according to claim 5, wherein rigidly coupling
comprises mounting on an unpeeled gum.
20. A method according to claim 5, wherein rigidly coupling
comprises mounting on a tooth.
21. A method according to claim 5, wherein said base element is
customized for a particular maxillofacial area.
22. A method according to claim 5, wherein said base element is
mass produced.
23. A method according to claim 5, wherein acquiring a
non-volumetric image comprises acquiring one or more 2D
transmission X-ray image of at least part of said maxillofacial
area.
24. A method according to claim 23, comprising viewing at least one
opaque portion of said base element to determine an allowed
drilling depth in said maxillofacial area.
25. A method according to claim 5, wherein acquiring a
non-volumetric image comprises optically scanning a surface of at
least part of said maxillofacial area.
26. A method according to claim 5, wherein acquiring a
non-volumetric image comprises reconstructing a surface geometry of
at least part of said maxillofacial area.
27. A method according to claim 5, wherein acquiring a
non-volumetric image comprises optically imaging at least part of
said maxillofacial area.
28. A method according to claim 5, wherein acquiring a
non-volumetric image comprises ultrasonically imaging at least part
of said maxillofacial area.
29. A method according to claim 5, wherein acquiring a
non-volumetric image comprises contact measurement using a
plurality of measured pins that penetrate gum tissue.
30. A method according to claim 12, wherein aiming comprises
adjusting one or more joints on said tool to achieve said
aiming.
31. A method according to claim 12, wherein said aiming comprises
aiming at least 2 degrees of freedom of movement and
orientation.
32. A method according to claim 12, wherein said aiming comprises
aiming at least 3 degrees of freedom of movement and
orientation.
33. A method according to claim 12, wherein said aiming comprises
aiming at least 5 degrees of freedom of movement and
orientation.
34. A method according to claim 12, wherein said aiming comprises
adjusting a depth of penetration of said tool.
35. A method according to claim 12, wherein said aiming comprises
planning a position and orientation of a tool path of said tool and
adjusting at least one of said position and orientation according
to said determining position.
36. A method according to claim 12, comprising monitoring at least
one of a position and orientation of said tool during said
aiming.
37. A method according to claim 36, wherein said monitoring
comprises displaying.
38. A method according to claim 37, wherein said displaying
comprises displaying an expected result of using said tool.
39. A method according to claim 37, wherein said displaying
comprises displaying a current effect of said tool.
40. A method according to claim 37, wherein said displaying
comprises displaying on a radiological image.
41. A method according to claim 37, wherein said displaying
comprises updating said display at least once per minute.
42. A method according to claim 37, wherein said displaying
comprises updating said display at least once per second.
43. A method according to claim 37, wherein said displaying
comprises calculating an expected layout of a dental prosthesis on
a bore formed using said tool; and displaying said expected layout
with said monitored position.
44. A method according to claim 37, wherein said displaying
comprises displaying a plurality of planned bores at different
locations simultaneously.
45. A method according to claim 5, comprising calculating an
expected layout of a dental prosthesis on a bore formed using said
tool; and displaying said expected layout with said determined
position.
46. A method according to claim 5, wherein said object is already
mounted on said base element during said rigidly coupling.
47. A method according to claim 5, comprising rigidly attaching
said object on said base element after said inserting.
48. A method according to claim 47, wherein attaching comprises
attaching to a predetermining place on said base element.
49. A method according to claim 47, wherein attaching comprises
attaching using an adhesive.
50. A method according to claim 47, wherein attaching comprises
attaching mechanically.
51. A method according to claim 5, wherein said object comprises a
dental soft tissue remover.
52. A method according to claim 5, wherein said object comprises a
needle.
53. A method according to claim 5, wherein said object comprises a
cutter.
54. A method according to claim 5, wherein said object comprises a
laser.
55. A method according to claim 5, wherein determining a position
comprises using a plurality of encoders embedded in said tool
guide
56. A method according to claim 5, wherein determining a position
comprises using a plurality of encoders embedded in said base.
57. A method according to claim 56, wherein said tool guide
comprises a drill guide and comprising adjusting said drill guide
to have a desired position and orientation.
58. A method according to claim 57, comprising attaching said
adjusted drill guide to a dental area.
59. A method according to claim 57, comprising locking said
adjusted drill guide to maintain its adjustment.
60. A method according to claim 12, wherein said tool comprises a
drill and comprising measuring a length of a drill burr of said
drill.
61. A method according to claim 5, wherein inserting an object
comprises fabricating said object.
62. A method according to claim 61, wherein fabricating comprises
drilling a bore in said object.
63. A dental tool guide base, comprising: a structure adapted to be
rigidly and removably attached to a gum-covered jaw; at least one
guide attachment point defined on said structure, which at least
one guide attachment point is adapted to rigidly attach a tool
guide section to said structure; and at least one registration mark
adapted to be identified relative to said structure.
64. A base according to claim 63, wherein said structure is
elastically distortable for said attaching.
65. A base according to claim 63, wherein said structure comprises
at least one attachment pin adapted for attaching to a gum covered
jaw.
66. A base according to claim 63, wherein said structure comprises
at least one attachment screw adapted for attaching to a gum
covered jaw.
67. A base according to claim 63, wherein said structure is in the
form of a stent.
68. A base according to claim 63, wherein said structure is adapted
to be attached to a small locality of said jaw.
69. A base according to claim 63, wherein said structure is
mass-produced.
70. A base according to claim 63, wherein said registration mark is
suitable for identification by optical surface scanning method.
71. A base according to claim 63, wherein said registration mark is
suitable for identification by an optical imaging method.
72. A base according to claim 63, wherein said registration mark is
suitable for identification by two-dimensional x-ray images.
73. A base according to claim 63, wherein said registration mark is
suitable for identification by ultra-sound imaging.
74. A base according to claim 63, wherein said attachment point is
a snap-locking attachment point.
75. A base according to claim 63, wherein said registration mark
and said guide attachment points are spatially separated.
76. A base according to claim 63, wherein said registration mark
and said guide attachment points are spatially overlapping.
77. A base according to claim 63, wherein said structure comprises
two opposing panels connected by at least one bridge element.
78. A base according to claim 77, wherein said structure comprises
two opposing panels connected by at least one bridge element.
79. A base according to claim 78, wherein said bridge includes an
aperture for guiding a drill bore therethrough.
80. A base according to claim 63, wherein said guide attachment
point is positioned to a side of said jaw when said structure is
attached to a gum-covered jaw.
81. A base according to claim 63, wherein said structure is adapted
to be attached to at least one tooth.
82. A base according to claim 63, wherein said structure is adapted
to mount on a gum.
83. A base according to claim 63, wherein said structure is
substantially transparent to x-rays, except for said registration
mark.
84. A base according to claim 77, comprising a radio-opaque grid on
at least one of said panels.
85. A base according to claim 77, comprising: a plurality of pins
in at least one of said panels, said pins being adapted to pierce
gum tissue but not bone; and at least one encoder which reads a
position of at least one of said pins.
86. A base according to claim 63, wherein said guide attachment
point is adapted to hold a block of material.
87. A base according to claim 63, comprising a solid block adapted
for engagement by said guide attachment point.
88. A dental tool guide, comprising: (a) a base section adapted to
be mechanically coupled to hard tissue; (b) an adjustable guide
section having a range of possible orientations in a vicinity of
said base section; and (c) at least one encoder adapted to fit in a
human mouth and configured to electronically report an orientation
of said guide section relative to said base section.
89. A tool guide according to claim 88, wherein said guide section
is mechanically coupled to said base section.
90. A tool guide according to claim 88, wherein said guide section
is mechanically decoupled from said base section.
91. A guide according to claim 88, comprising circuitry which
presents at least an indication of said orientation.
92. A guide according to claim 88, comprising circuitry which
transmits said report in a wireless manner.
93. A guide according to claim 88, comprising circuitry which
transmits said report in a wired manner.
94. A guide according to claim 88, wherein said base is in the form
of a surgical stent.
95. A guide according to claim 88, wherein said base is in the form
of a brace extending out of said mouth.
96. A guide according to claim 88, wherein said guide section
comprises at least one adjustable portion.
97. A guide according to claim 96, wherein said adjustable portion
is adapted to be locked.
98. A guide according to claim 97, wherein said locking comprises
mechanical locking.
99. A guide according to claim 97, wherein said locking comprises
locking by application of heat.
100. A guide according to claim 88, wherein said guide is opaque to
x-ray radiation.
101. A guide according to claim 88, wherein said guide is
transparent to x-ray radiation.
102. A guide according to claim 88, wherein said guide comprises at
least one radio-opaque marking.
103. A guide according to claim 88, wherein said encoder comprises
an optical encoder.
104. A guide according to claim 88, wherein at least one of said at
least one encoder is mounted on said base.
105. A guide according to claim 88, wherein at least one of said at
least one encoder is mounted on said guide.
106. A guide according to claim 88, wherein at least one of said at
least one encoder comprises at least two sensing parts, a sensed
part and a sensing part, each one of said parts mounted on a
different one of said guide and said base.
107. A guide according to claim 88, wherein said base is customized
to patient's jaw or teeth
108. A guide according to claim 88, wherein said base includes a
registration mark.
109. A guide according to claim 88, wherein said guide section is
in the form of an arm.
110. A guide according to claim 109, wherein said arm has at least
3 degrees of freedom relative to said base.
111. A guide according to claim 109, wherein said guide section
comprises: a plurality of joints which adjust said drill guide
section relative to said base; and a plurality of encoders which
directly measure orientation of said joints.
112. A guide according to claim 111, wherein said joints are
orthogonal to each other.
113. A guide according to claim 88, comprising a drilling depth
adjuster.
114. A dental tool guide aiming-device, comprising: a base adapted
to fixedly engage an adjustable tool guide; a guide holder adapted
to engage a guiding section of said tool guide; at least one
control adapted to move said guide holder and thereby change the
orientations of one or more joints of said drill guide.
115. An aiming device according to claim 114, wherein said guide
holder comprises a peg.
116. An aiming device according to claim 114, wherein said guide
holder prevents translation of said guide.
117. An aiming device according to claim 114, wherein said control
comprises a manual control.
118. An aiming device according to claim 114, wherein said control
comprises a motor.
119. An aiming device according to claim 114, comprising a
controlling attachment to a computer.
120. An aiming device according to claim 119, wherein said computer
includes a display adapted to display an effect of said
adjustment.
121. A aiming device according to claim 114, comprising a drill
depth adjuster.
122. An aiming device according to claim 121, comprising a set of
replaceable depth adjusters for different depths.
123. An aiming device according to claim 114, comprising a set of
sleeves for varying an outer diameter of said peg.
124. An aiming device according to claim 114, comprising a drill
length measuring element.
125. A dental tool guide, comprising: (a) a base section adapted to
be mechanically coupled to hard tissue; (b) an adjustable guide
section having a range of possible orientations in a vicinity of
said base section; and (c) a lock which selectively mechanically
locks said guide section to prevent further adjustment.
126. A guide according to claim 125, wherein said base is in the
form of a surgical stent.
127. A guide according to claim 125, wherein said base is in the
form of a brace extending out of said mouth.
128. A guide according to claim 125, wherein said guide section
comprises at least one adjustable portion.
129. A guide according to claim 125, wherein said locking comprises
mechanical locking.
130. A guide according to claim 129, wherein said locking comprises
tightening of a screw.
131. A guide according to claim 125, wherein said locking comprises
locking by application of heat.
132. A guide according to claim 125, wherein said guide is opaque
to x-ray radiation.
133. A guide according to claim 125, wherein said guide is
transparent to x-ray radiation.
134. A guide according to claim 125, wherein said guide comprises
at least one radio-opaque marking.
135. A guide according to claim 125, wherein said base is
customized to a patient's jaw or teeth.
136. A guide according to claim 125, wherein said base includes a
registration mark.
137. A guide according to claim 125, wherein said guide section is
in the form of an arm.
138. A guide according to claim 137, wherein said arm has at least
3 degrees of freedom relative to said base.
139. A guide according to claim 137, wherein said guide section
comprises a plurality of joints which adjust said drill guide
section relative to said base.
140. A guide according to claim 139, wherein said joints are
orthogonal to each other.
141. A guide according to claim 125, comprising a drilling depth
adjuster.
142. A guide according to claim 125, wherein said guide section is
permanently attached to said base.
143. A guide according to claim 125, wherein said guide section is
selectively attachable to said base.
Description
RELATED APPLICATIONS
[0001] This application is a continuation in part of U.S. Ser. No.
10/350,288, the disclosure of which is incorporated herein by
reference. This application is related to a PCT application filed
on Jan. 22, 2003, by same applicant in the Israel receiving office
and having attorney docket number 368-03870, the disclosure of
which is incorporated herein by reference.
FIELD OF THE INVENTION
[0002] The present application relates to the guiding of tools, for
example a dental drill.
BACKGROUND OF THE INVENTION
[0003] In manual applications where a high precision is required
over time, it is customary to use tool guides. For example, when
drilling holes in a jaw bone for tooth implants, a stent is
manufactured which fits the jaw and includes one or more bores
which serve to guide a drill in an exact trajectory towards the
jawbone.
[0004] Tool guides are also used in brain surgery, where a
sterotactic frame is mounted on a skull, imaged thereto and
registered to 3D images of the brain. A trajectory into the brain
is planned and the frame is set up to guide one or more tools along
this trajectory. Adjustable frames are also used for other organs,
such as the knee.
[0005] U.S. Pat. No. 5,562,448, the disclosure of which is
incorporated herein by reference describes a dental drill guide
positioning system using one or more position sensors to determine
a position of a dental drill and indicate, on an image, an expected
trajectory thereof.
SUMMARY OF THE INVENTION
[0006] A broad aspect of some embodiments of the invention relates
to tool guide sections which can be tracked and/or positioned
relative to a base station. In an exemplary embodiment of the
invention, such tracking is local and only includes determining
relative positions and/or orientations of elements in the immediate
vicinity of the tool guide section and the base section, for
examples in a mouth.
[0007] An aspect of some embodiments of the invention relates to
small and adjustable medical tool guides, for example for dental
use. In an exemplary embodiment of the invention, a tool guide
includes a base section for fixedly coupling to a human body
portion, and an adjustable guide section which can be adjusted in
at least three degrees of freedom relative to the base, after the
base is coupled to the body. Optionally, the degrees of freedom
include at least one position degree of freedom and at least one
orientation degree of freedom.
[0008] Optionally, the guide section and/or the base section
include one or more sensors which generate a signal responsive to
the adjustment of the guide section. Optionally, such indication is
transmitted using a wired or wireless transmitter provided in or
with the tool guide.
[0009] In an exemplary embodiment of the invention, the guide
section has the form of an articulating arm. Optionally, the arm is
lockable in position once adjusted. Optionally the tool guide is in
two separate parts where the guide section can be mounted on the
base section, for example after the base section is mounted to a
body and after the guide section is optionally locked in position.
In an alternative embodiment, the guide section has the form of a
rod extending from a box and including a tiltable tip.
[0010] In an exemplary embodiment of the invention, the tool guide
is designed to have an adjustment range smaller than 2 cm in
maximum extent. Optionally, the whole tool guide fits in a volume
suitable for fitting in a mouth, for example, smaller than 8 cm or
smaller than 5 cm in maximum extent. In one example, the guide is
used as a drill guide, small enough to fit in a mouth, with the
base being adapted to mount on a jaw or a tooth.
[0011] In an exemplary embodiment of the invention, the tool guide
is not mechanically coupled to the base. Instead, sensors (e.g.,
optical sensors) on the base and/or tool guide determine their
relative positions In an exemplary embodiment of the invention, the
tool guide sensors are mounted on a dental tool.
[0012] A broad aspect of some embodiments of the invention relates
to methods and apparatus for registering a base section to a hard
tissue, such as a jawbone. In an exemplary embodiment of the
invention, the base section is wholly contained in the mouth.
Optionally, the base section is registered to a previous image of
the hard tissue.
[0013] An aspect of some embodiments of the invention relates to a
method of registering a stent to an existing image of a jaw, for
example a 3D CT image data set. In an exemplary embodiment of the
invention, a stent is mounted on a jawbone after the existing image
is acquired. Optionally, this allows the acquisition of CT image to
be made without first committing to a particular dental treatment
process and/or at a different time and place. Optionally, however,
the CT image is acquired with the stent attached. Then, a
non-volumetric image of the stent and jawbone is acquired, for
example, a surface image acquired using optical scanning or using a
camera. Optionally, the stent includes one or more visible markers.
A jaw bone portion of the acquired surface image is then correlated
to the existing image. In an exemplary embodiment of the invention,
the stent includes a mounting point for a tool guide section, which
mounting point is suitable for rigid coupling of the tool guide
section to the jaw bone. In an exemplary embodiment of the
invention, the tool guide section is an adjustable arm of the type
described herein.
[0014] An aspect of some embodiments of the invention relates to a
registerable dental stent. In an exemplary embodiment of the
invention, the stent includes one or more x-ray opaque markers
arranged so that the stent position and/or orientation can be seen
in a 2D x-ray transmission image. Optionally, the stent is
otherwise partially or completely transparent to x-rays.
Optionally, the stent includes a marking which is identifiable
using optical surface scanning.
[0015] In an exemplary embodiment of the invention, the stent is
used to determine a depth to a mandibular canal. Optionally, the
stent includes means for determining a surface geometry of
underlying bone.
[0016] A broad aspect of some embodiments of the invention relates
to methods of using a base section and/or a tool guide section, for
example for dental applications.
[0017] An aspect of some embodiments of the invention relates to a
guiding stent for dental applications in which a jaw area or tooth
to be worked on is un-obscured. In one exemplary embodiment of the
invention, the stent includes two opposing base sections for
engaging a jaw bone on either side of the jaw and one or more
bridge sections which attach the base sections while leaving a
central area between the bridge sections un-obscured. A guide
section is optionally and/or selectively mountable on one of the
base sections so that it blocks access from at most one side of the
jaw bone. In an alternative embodiment of the invention, a base
section is adapted to be mounted on a tooth that is near the work
area on a jaw bone and includes a cantilevered section which acts
as a guide section and/or on which a guide section may be
mounted.
[0018] A broad aspect of some embodiments of the invention relates
to methods of adjusting and/or positioning of tool guide sections
relative to base sections.
[0019] An aspect of some embodiments of the invention relates to a
device for adjusting tool guides. In an exemplary embodiment of the
invention, the device includes a receptacle for holding at least
part of a guide section and a plurality of actuators, each adapted
to affect at least one degree of freedom of the guide section. In
an exemplary embodiment of the invention, the adjusting device
includes a manual or automated input interface, operative to
control the actuators, for example a port for an external
controller or a set of dials.
[0020] In an exemplary embodiment of the invention, the adjuster
device holds a base section and a guiding section of a tool guide
and, by user or machine manipulation, the relative positions and
orientations of the base and guiding sections are changed.
Optionally, the tool guide bends at its joints to conform to the
relative positions, such that for any particular relative position,
there may be more than one arm adjustment. In some implementations,
this method generally depends on the number of degrees of freedom
of the arm and the number of degrees of positional and
orientational change the adjuster is capable of.
[0021] In an exemplary embodiment of the invention, the adjuster
device includes two translation tables, each corresponding to a
different point along a desired bore and also includes means for
relative translation of the tables. In other embodiments of the
invention various hexapod designs are used.
[0022] In an exemplary embodiment of the invention, the adjuster
includes a receptacle adapted to measure a length of drill
guide.
[0023] There is thus provided in accordance with an exemplary
embodiment of the invention, a method of dental registration,
comprising:
[0024] rigidly coupling a base element to a maxillofacial area;
[0025] inserting an object comprising at least one of a tool and a
tool guide into a mouth in said maxillofacial area; and
[0026] determining a position of said object relative to said rigid
element without a reference element outside of said mouth.
Optionally, said base element comprises a rigid element.
[0027] In an exemplary embodiment of the invention, the method
comprises acquiring a 3D radiological image of at least a part of
said maxillofacial area. Optionally, the method comprises acquiring
a non-volumetric image of at least a part of said dental area
including at least a part of said base element. Optionally, the
method comprises:
[0028] identifying at least one registration mark of said rigid
element on said non-volumetric image; and
[0029] registering said image to said 3D image, thereby registering
said registration mark to said area.
[0030] In an exemplary embodiment of the invention, the method
comprises:
[0031] acquiring a first image of at least a part of said
maxillofacial area;
[0032] acquiring a non-volumetric image of least a part of said
dental area including at least a part of said base element;
[0033] identifying at least one registration mark of said rigid
element on said non-volumetric image; and
[0034] registering said image to said first image, thereby
registering said registration mark to said area. Optionally, said
first image comprises a surface image obtained using a plurality of
measurable pins which penetrate gum tissue to bone tissue.
[0035] In an exemplary embodiment of the invention, said
non-volumetric image comprises a 2D transmission image.
[0036] In an exemplary embodiment of the invention, determining
comprises setting a desired position, and comprising selecting a
desired relative position.
[0037] In an exemplary embodiment of the invention, determining
comprises measuring an existing position. Optionally, determining
comprises adjusting said object to a new position responsive to
said measured position.
[0038] In an exemplary embodiment of the invention, determining
comprises aiming said tool using said position, at said
maxillofacial area.
[0039] In an exemplary embodiment of the invention, rigidly
coupling comprises inserting at least one pin into gum tissue of
said maxillofacial area.
[0040] In an exemplary embodiment of the invention, rigidly
coupling comprises coupling using a clamp.
[0041] In an exemplary embodiment of the invention, rigidly
coupling comprises releasing said base element to elastically
engage said maxillofacial area.
[0042] In an exemplary embodiment of the invention, rigidly
coupling comprises attaching using at least one screw.
[0043] In an exemplary embodiment of the invention, rigidly
coupling comprises attaching to a single portion of said
maxillofacial area.
[0044] In an exemplary embodiment of the invention, rigidly
coupling comprises attaching said rigid element to be adjacent to
at least 35% of a jawbone of said maxillofacial area.
[0045] In an exemplary embodiment of the invention, rigidly
coupling comprises mounting on an unpeeled gum.
[0046] In an exemplary embodiment of the invention, rigidly
coupling comprises mounting on a tooth.
[0047] In an exemplary embodiment of the invention, said base
element is customized for a particular maxillofacial area.
[0048] In an exemplary embodiment of the invention, base element is
mass produced.
[0049] In an exemplary embodiment of the invention, acquiring a
non-volumetric image comprises acquiring one or more 2D
transmission X-ray image of at least part of said maxillofacial
area. Optionally, the method comprises viewing at least one opaque
portion of said base element to determine an allowed drilling depth
in said maxillofacial area.
[0050] In an exemplary embodiment of the invention, acquiring a
non-volumetric image comprises optically scanning a surface of at
least part of said maxillofacial area.
[0051] In an exemplary embodiment of the invention, acquiring a
non-volumetric image comprises reconstructing a surface geometry of
at least part of said maxillofacial area.
[0052] In an exemplary embodiment of the invention, acquiring a
non-volumetric image comprises optically imaging at least part of
said maxillofacial area.
[0053] In an exemplary embodiment of the invention, acquiring a
non-volumetric image comprises ultrasonically imaging at least part
of said maxillofacial area.
[0054] In an exemplary embodiment of the invention, acquiring a
non-volumetric image comprises contact measurement using a
plurality of measured pins that penetrate gum tissue.
[0055] In an exemplary embodiment of the invention, aiming
comprises adjusting one or more joints on said tool to achieve said
aiming.
[0056] In an exemplary embodiment of the invention, said aiming
comprises aiming at least 2 degrees of freedom of movement and
orientation.
[0057] In an exemplary embodiment of the invention, said aiming
comprises aiming at least 3 degrees of freedom of movement and
orientation.
[0058] In an exemplary embodiment of the invention, said aiming
comprises aiming at least 5 degrees of freedom of movement and
orientation.
[0059] In an exemplary embodiment of the invention, said aiming
comprises adjusting a depth of penetration of said tool.
[0060] In an exemplary embodiment of the invention, said aiming
comprises planning a position and orientation of a tool path of
said tool and adjusting at least one of said position and
orientation according to said determining position.
[0061] In an exemplary embodiment of the invention, the method
comprises monitoring at least one of a position and orientation of
said tool during said aiming. Optionally, said monitoring comprises
displaying. Optionally, said displaying comprises displaying an
expected result of using said tool. Alternatively or additionally,
said displaying comprises displaying a current effect of said tool.
Alternatively or additionally, said displaying comprises displaying
on a radiological image. Alternatively or additionally, said
displaying comprises updating said display at least once per
minute. Alternatively or additionally, said displaying comprises
updating said display at least once per second. Alternatively or
additionally, said displaying comprises calculating an expected
layout of a dental prosthesis on a bore formed using said tool; and
displaying said expected layout with said monitored position.
Alternatively or additionally, said displaying comprises displaying
a plurality of planned bores at different locations
simultaneously.
[0062] In an exemplary embodiment of the invention, the method
comprises calculating an expected layout of a dental prosthesis on
a bore formed using said tool; and displaying said expected layout
with said determined position.
[0063] In an exemplary embodiment of the invention, said object is
already mounted on said base element during said rigidly
coupling.
[0064] In an exemplary embodiment of the invention, the method
comprises rigidly attaching said object on said base element after
said inserting. Optionally, attaching comprises attaching to a
predetermining place on said base element. Alternatively or
additionally, attaching comprises attaching using an adhesive.
Alternatively or additionally, attaching comprises attaching
mechanically.
[0065] In an exemplary embodiment of the invention, said object
comprises a dental soft tissue remover. Alternatively or
additionally, said object comprises a needle. Alternatively or
additionally, said object comprises a cutter. Alternatively or
additionally, said object comprises a laser.
[0066] In an exemplary embodiment of the invention, determining a
position comprises using a plurality of encoders embedded in said
tool guide
[0067] In an exemplary embodiment of the invention, determining a
position comprises using a plurality of encoders embedded in said
base. Optionally, said tool guide comprises a drill guide and
comprising adjusting said drill guide to have a desired position
and orientation. Optionally, the method comprises attaching said
adjusted drill guide to a dental area. Alternatively or
additionally, the method comprises locking said adjusted drill
guide to maintain its adjustment.
[0068] In an exemplary embodiment of the invention, said tool
comprises a drill and comprising measuring a length of a drill burr
of said drill.
[0069] In an exemplary embodiment of the invention, inserting an
object comprises fabricating said object. Optionally, fabricating
comprises drilling a bore in said object.
[0070] There is also provided in accordance with an exemplary
embodiment of the invention, a dental tool guide base,
comprising:
[0071] a structure adapted to be rigidly and removably attached to
a gum-covered jaw;
[0072] at least one guide attachment point defined on said
structure, which at least one guide attachment point is adapted to
rigidly attach a tool guide section to said structure; and
[0073] at least one registration mark adapted to be identified
relative to said structure. Optionally, said structure is
elastically distortable for said attaching. Alternatively or
additionally, said structure comprises at least one attachment pin
adapted for attaching to a gum covered jaw. Alternatively or
additionally, said structure comprises at least one attachment
screw adapted for attaching to a gum covered jaw.
[0074] In an exemplary embodiment of the invention, said structure
is in the form of a stent.
[0075] Optionally, said structure is adapted to be attached to a
small locality of said jaw.
[0076] In an exemplary embodiment of the invention, said structure
is mass-produced.
[0077] In an exemplary embodiment of the invention, said
registration mark is suitable for identification by optical surface
scanning method.
[0078] In an exemplary embodiment of the invention, said
registration mark is suitable for identification by an optical
imaging method.
[0079] In an exemplary embodiment of the invention, said
registration mark is suitable for identification by two-dimensional
x-ray images.
[0080] In an exemplary embodiment of the invention, said
registration mark is suitable for identification by ultra-sound
imaging.
[0081] In an exemplary embodiment of the invention, said attachment
point is a snap-locking attachment point.
[0082] In an exemplary embodiment of the invention, said
registration mark and said guide attachment points are spatially
separated.
[0083] In an exemplary embodiment of the invention, said
registration mark and said guide attachment points are spatially
overlapping.
[0084] In an exemplary embodiment of the invention, said structure
comprises two opposing panels connected by at least one bridge
element. Optionally, said structure comprises two opposing panels
connected by at least one bridge element. Optionally, said bridge
includes an aperture for guiding a drill bore therethrough.
[0085] In an exemplary embodiment of the invention, said guide
attachment point is positioned to a side of said jaw when said
structure is attached to a gum-covered jaw.
[0086] In an exemplary embodiment of the invention, said structure
is adapted to be attached to at least one tooth.
[0087] In an exemplary embodiment of the invention, said structure
is adapted to mount on a gum.
[0088] In an exemplary embodiment of the invention, said structure
is substantially transparent to x-rays, except for said
registration mark.
[0089] In an exemplary embodiment of the invention, the base
comprises a radio-opaque grid on at least one of said panels.
[0090] In an exemplary embodiment of the invention, the base
comprises:
[0091] a plurality of pins in at least one of said panels, said
pins being adapted to pierce gum tissue but not bone; and at least
one encoder which reads a position of at least one of said
pins.
[0092] In an exemplary embodiment of the invention, said guide
attachment point is adapted to hold a block of material.
[0093] In an exemplary embodiment of the invention, the base
comprises a solid block adapted for engagement by said guide
attachment point.
[0094] There is also provided in accordance with an exemplary
embodiment of the invention, a dental tool guide, comprising:
[0095] (a) a base section adapted to be mechanically coupled to
hard tissue;
[0096] (b) an adjustable guide section having a range of possible
orientations in a vicinity of said base section; and
[0097] (c) at least one encoder adapted to fit in a human mouth and
configured to electronically report an orientation of said guide
section relative to said base section. Optionally, said guide
section is mechanically coupled to said base section.
[0098] In an exemplary embodiment of the invention, said guide
section is mechanically decoupled from said base section.
[0099] In an exemplary embodiment of the invention, said guide
comprises circuitry which presents at least an indication of said
orientation.
[0100] In an exemplary embodiment of the invention, said guide
comprises circuitry which transmits said report in a wireless
manner.
[0101] In an exemplary embodiment of the invention, said guide
comprises circuitry which transmits said report in a wired
manner.
[0102] In an exemplary embodiment of the invention, said base is in
the form of a surgical stent.
[0103] In an exemplary embodiment of the invention, said base is in
the form of a brace extending out of said mouth.
[0104] In an exemplary embodiment of the invention, said guide
section comprises at least one adjustable portion. Optionally, said
adjustable portion is adapted to be locked. Optionally, said
locking comprises mechanical locking. Alternatively or
additionally, said locking comprises locking by application of
heat.
[0105] In an exemplary embodiment of the invention, said guide is
opaque to x-ray radiation.
[0106] In an exemplary embodiment of the invention, said guide is
transparent to x-ray radiation.
[0107] In an exemplary embodiment of the invention, said guide
comprises at least one radio-opaque marking.
[0108] In an exemplary embodiment of the invention, said encoder
comprises an optical encoder.
[0109] In an exemplary embodiment of the invention, at least one of
said at least one encoder is mounted on said base.
[0110] In an exemplary embodiment of the invention, at least one of
said at least one encoder is mounted on said guide.
[0111] In an exemplary embodiment of the invention, at least one of
said at least one encoder comprises at least two sensing parts, a
sensed part and a sensing part, each one of said parts mounted on a
different one of said guide and said base.
[0112] In an exemplary embodiment of the invention, said base is
customized to a patient's jaw or teeth.
[0113] In an exemplary embodiment of the invention, said base
includes a registration mark.
[0114] In an exemplary embodiment of the invention, said guide
section is in the form of an arm. Optionally, said arm has at least
3 degrees of freedom relative to said base.
[0115] In an exemplary embodiment of the invention, said guide
section comprises:
[0116] a plurality of joints which adjust said drill guide section
relative to said base; and
[0117] a plurality of encoders which directly measure orientation
of said joints. Optionally, said joints are orthogonal to each
other.
[0118] In an exemplary embodiment of the invention, said guide
comprises a drilling depth adjuster.
[0119] There is also provided in accordance with an exemplary
embodiment of the invention, a dental tool guide aiming-device,
comprising:
[0120] a base adapted to fixedly engage an adjustable tool
guide;
[0121] a guide holder adapted to engage a guiding section of said
tool guide;
[0122] at least one control adapted to move said guide holder and
thereby change the orientations of one or more joints of said drill
guide. Optionally, said guide holder comprises a peg.
[0123] In an exemplary embodiment of the invention, said guide
holder prevents translation of said guide.
[0124] In an exemplary embodiment of the invention, said control
comprises a manual control.
[0125] In an exemplary embodiment of the invention, said control
comprises a motor.
[0126] In an exemplary embodiment of the invention, the device
comprises a controlling attachment to a computer. Optionally, said
computer includes a display adapted to display an effect of said
adjustment.
[0127] In an exemplary embodiment of the invention, the device
comprises a drill depth adjuster. Optionally, the device comprises
a set of replaceable depth adjusters for different depths.
[0128] In an exemplary embodiment of the invention, the device
comprises a set of sleeves for varying an outer diameter of said
peg.
[0129] In an exemplary embodiment of the invention, the device
comprises a drill length measuring element.
[0130] There is also provided in accordance with an exemplary
embodiment of the invention, a dental tool guide, comprising:
[0131] (a) a base section adapted to be mechanically coupled to
hard tissue;
[0132] (b) an adjustable guide section having a range of possible
orientations in a vicinity of said base section; and
[0133] (c) a lock which selectively mechanically locks said guide
section to prevent further adjustment. Optionally, said base is in
the form of a surgical stent.
[0134] In an exemplary embodiment of the invention, said base is in
the form of a brace extending out of said mouth.
[0135] In an exemplary embodiment of the invention, said guide
section comprises at least one adjustable portion.
[0136] In an exemplary embodiment of the invention, said locking
comprises mechanical locking. Optionally, said locking comprises
tightening of a screw.
[0137] In an exemplary embodiment of the invention, said locking
comprises locking by application of heat.
[0138] In an exemplary embodiment of the invention, said guide is
opaque to x-ray radiation.
[0139] In an exemplary embodiment of the invention, guide is
transparent to x-ray radiation.
[0140] In an exemplary embodiment of the invention, said guide
comprises at least one radio-opaque marking.
[0141] In an exemplary embodiment of the invention, said base is
customized to patient's jaw or teeth
[0142] In an exemplary embodiment of the invention, said base
includes a registration mark.
[0143] In an exemplary embodiment of the invention, said guide
section is in the form of an arm. Optionally, said arm has at least
3 degrees of freedom relative to said base.
[0144] In an exemplary embodiment of the invention, said guide
section comprises a plurality of joints which adjust said drill
guide section relative to said base. Optionally, said joints are
orthogonal to each other.
[0145] In an exemplary embodiment of the invention, the guide
comprises a drilling depth adjuster.
[0146] In an exemplary embodiment of the invention, said guide
section is permanently attached to said base.
[0147] In an exemplary embodiment of the invention, said guide
section is selectively attachable to said base.
BRIEF DESCRIPTION OF THE FIGURES
[0148] Non-limiting embodiments of the invention will be described
with reference to the following description of exemplary
embodiments, in conjunction with the figures. The figures are
generally not shown to scale and any sizes are only meant to be
exemplary and not necessarily limiting. In the figures, identical
structures, elements or parts that appear in more than one figure
are preferably labeled with a same or similar number in all the
figures in which they appear, in which:
[0149] FIG. 1 is a schematic illustration of a dental guiding
system in accordance with an exemplary embodiment of the
invention;
[0150] FIG. 2 is a flowchart of a process of dental drill guiding,
in accordance with an exemplary embodiment of the invention;
[0151] FIGS. 3A-3C are schematic views of a dental tool guide, in
accordance with an exemplary embodiment of the invention;
[0152] FIG. 3D is a schematic showing of a tool guide base with
various registration marks, in accordance with an exemplary
embodiment of the invention;
[0153] FIG. 4A is an schematic external view, and FIG. 4B a
cross-sectional schematic view of a tool guide section, in
accordance with an exemplary embodiment of the invention;
[0154] FIG. 5A is an schematic external view and FIG. 5B a
cross-sectional schematic view of a guiding section adjusting
device, in accordance with an exemplary embodiment of the
invention;
[0155] FIG. 6A is a schematic side cross-sectional view of a
pin-based dental positioning device, in accordance with an
exemplary embodiment of the invention;
[0156] FIG. 6B is a blow-apart view of an exemplary implementation
of a tool guide, in accordance with an exemplary embodiment of the
invention;
[0157] FIGS. 7A and 7B show a side schematic view and a top
schematic view of a side-mounted guide, in accordance with an
exemplary embodiment of the invention;
[0158] FIG. 8A shows a schematic tool guide having only single
wing, in accordance with an exemplary embodiment of the
invention;
[0159] FIG. 8B shows a denture-based tool guide, in accordance with
an exemplary embodiment of the invention;
[0160] FIG. 8C shows a brace-based tool guide, in accordance with
an exemplary embodiment of the invention;
[0161] FIG. 9A shows a schematic smart guide section, in which one
or more sensors are included to report on joint positions of the
guide, in accordance with an exemplary embodiment of the
invention;
[0162] FIG. 9B is a cross-sectional view of the guide section of
FIG. 9A, in accordance with an exemplary embodiment of the
invention;
[0163] FIG. 10 shows a schematic tool guide including an x-ray
opaque grid, in accordance with an exemplary embodiment of the
invention;
[0164] FIG. 11 is a schematic showing of a tool guide including a
custom bored guide section, in accordance with an exemplary
embodiment of the invention;
[0165] FIGS. 12 and 13 illustrate a contact-less sensing tool
guide, in accordance with an exemplary embodiment of the invention;
and
[0166] FIG. 14 illustrates an alternative contact-less sensing tool
guide, in accordance with an exemplary embodiment of the
invention.
DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS
General Overview of System
[0167] FIG. 1 is a schematic illustration of a dental guiding
system 100 in accordance with an exemplary embodiment of the
invention. A dental treatment, for example tooth implantation or
prosthesis attachment, is desired at a treatment location/area 104
of a jawbone 102 (lower jaw bone shown for clarity). As will be
described below in more detail, a dental tool guide 106 comprising
a base section 108 and an adjustable guide section 110 is mounted
adjacent location 104. A drill 112 (or other dental tool, for
example), is guided by guide section 110. A scanner 114 is
optionally used for registration, as described below. A computer
126 or other controller is optionally provided, for example, for
planning and/or displaying a path (bore) 122 on a radiological
image 124 using an optional display 120, for controlling an
optional tool guide adjuster 132, for receiving and/or for sending
data using an optional wireless or wired link 128. A user input
device, such as a keyboard 130 is optionally provided.
Exemplary Guiding Process
[0168] FIG. 2 is a flowchart 200 of a process of dental drill
guiding, in accordance with an exemplary embodiment of the
invention.
[0169] At 202, a patient is diagnosed as requiring some dental
treatment, for example, a tooth implantation.
[0170] At 204, a radiological image of jaw 102 including treatment
area 104 is acquired, for example, a 3D CT image. In some
embodiments, this image is not essential, for example, by using a
pin array, for example as described in U.S. Ser. No. 10/350,288,
the disclosure of which is incorporated herein by reference, to
acquire a map of the bone surface.
[0171] At 206, the location of the implant and/or a suitable bore
to be made in the jaw are planned, for example, based on the image.
In some cases, several possible bores (or a range of bores) are
planned, with the final bore being selected later, for example,
during drilling.
[0172] At 208, tool guide 106 is attached to jaw 102, typically at
or adjacent area 104. In some embodiments, only base section 108 is
attached. In an exemplary embodiment of the invention, tool guide
106 is only attached at the vicinity, for example, within a
distance of 1-3 teeth form the implant area. In other embodiments,
the attachment can be to a greater portion of the jaw, for example,
35%. In an exemplary embodiment of the invention, the gum is not
peeled prior to attachment, but in some embodiments it may be.
Optionally, base section 108 is attached to a bone. In some
embodiments of the invention, base section 108 is adapted to attach
to various structures, for example, implants, crowns, teeth and
jaws. Optionally, base section 108 includes modular attachment
elements, one on either side (e.g., along the line of the jaw), so
that section 108 can attach to one structure on one end thereof and
to a second structure at a different end thereof. Such modular
attachment elements can be, for example, attached by a snap-fitting
or a screw to the body of base section 108.
[0173] At 210, part of jaw 102 is scanned, at least including a
part of tool guide 106. In one example, guide 106 includes one or
more marker or feature which can be identified on the scan and
whose position and/or orientation relative to features of the jaw
can be determined from the scan. In an exemplary embodiment of the
invention, an optical scanner 114 is used for the scanning.
Alternatively, a 2D X-ray system is used for the scanning. In an
exemplary embodiment of the invention, a further volumetric
radiological image, for example x-ray CT, with its associated cost
and inconvenience, is avoided.
[0174] Optionally, instead of scanning inside the mouth, an
impression (e.g., using impression clay) is taken of the mouth
while base section 108 is mounted in the mouth. This impression is
then scanned outside the body, where it is more accessible.
[0175] In an exemplary embodiment of the invention, the scanner
used is a line scanner.
[0176] In another embodiment an ultrasound imager is used, for
example an imager which generates a topographical map of the
surface, or an imager which generates an image of the inside of the
jaw.
[0177] In another embodiment, a contact scanner is used, optionally
with a position sensor which allows the position of a contact point
of the scanner to be tracked in space.
[0178] In another embodiment, an imaging sensor is used for
scanning.
[0179] In an exemplary embodiment of the invention, the scanned
data is used to reconstruct a surface geometry (i.e., topographical
map) of at least a part of area 104, including base section 108.
Various surface matching and image correlation methods known in the
art may used be to combine the acquired data into a surface map
and/or for registering the acquired data to the 3D image
(below).
[0180] Exemplary scanner include: (a) FastSCAN Cobra by Polhemus,
described at http://www.polhemus.corn/fastscan.htm; (b) Freepoint
3D hand held Sonic Digitizer by GTCO, described at
http://www.gtco.com/productfreepoint3d.htm; (c) Pix--4/30 by Roland
DGA: a DESKTOP 3d Active Piezo Sensor scanner, described at
http://www.rolanddga.com/products/3D/scanners/pix4.sub.--30/default.asp;
and (d) A stylus device which can be used to touch landmarks in
mouth and on bridge, for example, Microscribe by Immersion,
described in http://www.immersion.com/digitizer/.
[0181] At 212, a drill type to use and/or an implant to use are
optionally selected. Alternatively or additionally, this may be
performed earlier, for example as part of optional planning 206, or
later, after registration.
[0182] At 214, tool guide 106 is registered to the earlier acquired
3D image, for example using the surface scan acquired at 210. In an
exemplary embodiment of the invention, one or more registration
marks on guide 106 are used to identify the position and/or
orientation of guide 106 in the surface map. Alternatively, the
outside contour of guide 106 may be used for this purpose. Other
registration techniques may be used as well. Once this registration
is complete, a display of the image, showing both tool guide 106
and a planned bore may be generated (e.g., bore 122). In some
embodiments, planning of drilling trajectory is performed at this
point in time.
[0183] At 216, guide section 110 is optionally adjusted to fit the
planned drilling trajectory. In some embodiments of the invention,
an external adjusting tool is used, into which guide section 110 is
placed. In other embodiments of the invention, guide section 110
includes one or more sensors which report its position, e.g., via
wireless link 128. Optionally, the guide section is manipulated and
display 120 shows a resulting bore in real-time. At the end of the
adjusting, guide section 110 is optionally locked to have a frozen
guiding configuration. Reference 118 is a cross-sectional view of
jaw 102 along bore 122, showing bore 122.
[0184] At 218, guide section 110 is optionally rigidly attached to
base section 108, for example, if it was not so attached
before.
[0185] At 220, a physician uses tool guide 106 to guide drilling
and/or other procedures, such as tissue punching. An exemplary and
non-limiting list of tools which may be optionally guided using the
methods described herein are: drill guide, soft tissue remover,
tool guide, needle, cutter, laser, marking pointer and/or ruler
[0186] In an exemplary embodiment of the invention, the display is
updated rapidly, for example, faster than once a minute, once a
second or even 10 times a second or faster. Such an update rate
allows a substantially real time display of the tool position on
the display.
[0187] In an exemplary embodiment of the invention, guide section
110 is locked. However, in other embodiments, for example if the
attachment of base 108 to the jaw is not strong, guide section 110
is left free. In this case, it is the user's responsibility to
maintain a correct trajectory. Optionally, the display can be used
to guide the user as to the effect and/or as to any deviations from
the planned trajectory. Optionally, the tool acts as a user input
device to manipulate the display, for example, by moving the bore
and thus a resulting position of the mounted prosthesis.
[0188] In an exemplary embodiment of the invention, an effect of
the procedure is shown on the display, for example an angle or
position of an implant. In an exemplary embodiment of the
invention, a complete restoration is planned, for example, one
including two tooth implants. A display can show the expected
position of the implants and any prosthesis attached to them. Thus,
a user can estimate the effect on the final result of the dental
restoration, caused by changing a tool trajectory. Optionally, any
planned prosthesis is digitally scanned so that it can be displayed
and manipulated.
[0189] At 222, tool guide 106 is optionally removed from jaw
102.
[0190] At 224, some or all of tool guide 106 is optionally disposed
of, for example, to ensure sterility, sharpness and/or having a
correct spatial configuration. Alternatively or additionally, some
or all of tool guide 106 is sterilized and reused.
Two Wing Tool Guide
[0191] FIGS. 3A-3C shows tool guide 106 in an exemplary two wing
implementation thereof. FIG. 3A is an isometric view. FIG. 3B is a
side view (along a jaw) and FIG. 3C is a top view (from above a
lower jaw).
[0192] The general structure shown is two side panels 308 and 310
interconnected by two wings 314 and 316. In an exemplary embodiment
of the invention, the wings are positioned so that they do not
interfere with dental operations and/or viewing of the treated
area.
[0193] A guide section 110, described in more detail below, is
rigidly attachable to guide 106, for example on top of panel 310.
While a variety of attachment mechanisms may be used, in this
embodiment, a small base 302 of guide section 110 fits in a recess
301 formed in panel 310 and is locked into position by a movable
flap 304 which is pivotally attached to base section 108 by
pin-hinges 306. Optionally, flap 304 is elastically urged towards
panel 310, to enhance the attachment rigidity.
[0194] Optionally, the wings protect guide section 110 from contact
of the opposing jaw and/or tools.
[0195] In an exemplary embodiment of the invention, wings 314 and
316 provide some degree of elasticity. When mounted on a jaw, if
the jaw is wider than the distance between panels 308 and 310, the
panels move apart, while being elastically urged towards each
other, and the jaw, by the wings. Possibly, different sized tool
guides are provided for different locations and/or patient sizes.
It should be noted, however, that it may not be necessary to inform
the computerized system of the particular size selected, for
example, if the registration point is always at a same location
relative to the guide section. In an exemplary embodiment of the
invention, the registration point is provided adjacent (and
optionally rigidly coupled) the working area, to reduce errors.
[0196] Optionally, a plurality of nubs 312 are formed on the panels
and provide a better engagement of gum tissue. Alternatively or
additionally, one or more of the nubs serves to limit the depth of
insertion of the tool guide, by preventing tool guide 106 from
being pushed down (or up, in an upper jaw) too far.
[0197] Optionally, alternatively or additionally to nubs 312, one
or more attachment screws may be provided, for example, a screw
320, which pass through one or both of panels 308 and 310 and can,
for example depending on the design, penetrate to the jaw bone or
stay on the gum. Alternatively or additionally, one or more clamp
elements may be provided.
[0198] FIG. 3D is a schematic showing of tool guide base 108 with
various registration marks, in accordance with an exemplary
embodiment of the invention.
[0199] As noted above, in an exemplary embodiment of the invention,
optical registration is used to determine a position of tool guide
106 relative to jaw 102. Optionally, an optically visible
registration mark 350 is provided in recess 301. Other possible
positions for reference marks includes marks 352 and 354 near
recess 301 and marks 358 and 356 on the wings. Other reference
positions may be provided as well. In an exemplary embodiment of
the invention, panel 310 is thin, for example, between 0.5 and 2
mm, where it contacts the jaw. In such an embodiment, a
registration mark 360 is optionally provided thereon. Optionally,
the marks are engraved. Alternatively, the marks are colored in or
painted on.
[0200] Optionally, one or more holes 330 are provided in tool guide
106, for example in wings 314 and/or 316. In an exemplary
embodiment of the invention, holes 330 may be engaged by a suitable
tool which spreads apart panels 308 and 310. When released, wings
314 and 316 elastically urge nubs 312 against gum tissue and lock
device 300 in place.
[0201] Regarding fixation strength. In some embodiments of the
invention, the fixation of device 106 to the gum is strong enough
to withstand moments and forces typical of drilling. In other
embodiments, the fixation is strong enough to prevent inadvertent
movement, but cannot withstand strong moments typical of drilling.
Optionally, when weaker fixation is used, the tool guide section
(described below) is not locked, but is associated with sensors
which report its position to a user.
[0202] As noted above, other tool guide designs may be used, and
several variations are shown below. In some embodiments of the
invention, what is desirable about a tool guide is that it be
rigidly attachable to a jaw, that a guide section thereof be
rigidly coupled to it, and through it to the jaw and that the tool
guide be registerable.
Guide Section
[0203] FIGS. 4A and 4B are a side isometric view and a matching
cross-sectional view of guide section 110, in accordance with an
exemplary embodiment of the invention.
[0204] The general structure shown is a an articulated arm having
base 302 at one end and a guide tube 402 at another end, which tube
serves as a guide for a drill. Optionally, one or more lumen
reducing or modifying inserts 450 are provided in guide tube 402.
In the design shown, locking of the guide section to a particular
configuration is achieved by rotating a screw 410 so that two
opposing side sections of the arm are brought together, increasing
friction in all the other joints, which are formed of balls which
can rotate in spaces defined between the two opposing side
sections.
[0205] In the particular embodiment shown, two 2D joints and one 1D
joint are provided. In other embodiments, a different number and/or
types of joints may be used. Tube 402 is attached to an arm segment
406 by a joint 404 containing a ball 418 (e.g., a ball pivot
joint). Arm segment 406 is attached to an arm segment 412 by a
plain joint 408, in which screw 410 acts as a hinge and locking
element. Arm segment 412 is attached to base 302 by a joint 414
including an internal ball 420. The two side sections of the arm
are schematically indicated as references 416 and 422. Screw 410
optionally screws into an element 440 (FIG. 4B).
[0206] In an alternative implementation of a locking mechanism, a
pair of crescent-shaped stops 444 and 442 are provided (other
shapes may be used), each such stop selectively coupling element
440 to balls 418 and 420. Optionally, element 440 is in the shape
of a cone, so that as screw 410 is tightened, stops 442 and 44 are
pressed outwards from the cone element towards balls 418 and
420.
[0207] Optionally, a different locking mechanism is used. In one
example, a magnetic locking mechanism is used. In another example,
the arm is crimped, to effect locking. In another example, an
adhesive drop is applied to the joint(s). In another example, the
arm is heated so that a meltable material or a glue flows and locks
the joints. Optionally, an electric resistor is provided in the arm
(not shown) and is electrified to provide the heat. In an
embodiment where an adjuster is used (FIG. 5, below), the adjuster
may apply current and/or heat. Similar mechanisms (e.g., magnetic
attraction, adhesive, heat-flowing glue) may be used to attach the
arm to base section 108.
[0208] Guide 106 may be formed of any dentally acceptable material,
for example, titanium, ceramic, stainless steel and/or plastic.
Typically, disposable parts will be made of cheaper materials,
non-disposable parts will be made of sterilizable materials, and
parts which are elastic will be made of metal, however, this is not
essential.
[0209] Referring back to insert 450, In an exemplary embodiment of
the invention, insert 450 includes a handle 452 that extends out of
a mouth of the patient and is optionally held by a dentist. This
insert may also have one or both of the following functions:
protecting guide 402 from the drill and stabilizing the drilling
direction.
[0210] In an exemplary embodiment of the invention, insert 450
comprises a tube 456 having an inner diameter matched to the drill
bit being used. Optionally, tube 456 is coated on the inside with a
friction reducing coating. A flange 454 on insert 450 optionally
has a thickness which determines a drilling depth.
Guide Section Adjuster
[0211] FIG. 5A is an outside view and FIG. 5B a cross-sectional
views of a guide section adjusting device 500 used to set guide
section 110, in accordance with an exemplary embodiment of the
invention.
[0212] Adjuster 500 works under the following principle, base 302
and guiding tube 402 of guide section 110 are first mounted on
adjuster 500 so that each is held in place. Then the relative
positions and orientations of base 302 and guiding tube 402 are
modified so that if base 302 were attached to base section 108,
guiding tube 402 would point along bore 122. Then, guide section
110 is optionally locked and removed from adjuster 500.
[0213] In device 500, base 302 is mounted in a base station 502 and
guiding tube 402 is mounted on a spindle 504. Base 302 optionally
snap-fits to base station 502. Optionally a locking mechanism (not
shown) is used. Other connection methods may be alternatively or
additionally used as well, for example a magnetic attachment.
Spindle 504 includes a bottom stop 506 on which guide tube 402 can
rest. Optionally, an upper stop 508 is provided to prevent guide
tube 402 from slipping off. Optionally, stop 506 and/or stop 508
can have their axial positions adjusted, for example, by being
threaded to spindle 504.
[0214] Device 500 comprises two plane control units, 510 and 560,
both of which are optionally of similar design and each of which
optionally controls the position and orientation of spindle 504 in
one of two perpendicular planes which intersect at spindle 504.
[0215] FIG. 5B shows a cross-section view of device 500 along the
plane controlled by control unit 510. The following discussion
focuses on control unit 510, but it should be understood that in
this embodiment of the invention, control unit 560 operates in a
same manner.
[0216] Spindle 504 is held by two X-Y tables 512 and 514. Control
unit 510 controls the absolute and relative "X" position of the two
tables, thereby setting the spindle position and angle in the "X"
plane. Spindle 504 is held in table 512 by a joint 516 and in table
514 by a joint 518. Various types of joints may be used, for
example a ball in socket joint for joint 516, or a cylindrical
joint. A rod 520 couples control unit 510 to table 512 and a
control rod 522 couples control unit 512 to table 514.
[0217] Referring to the manipulation of control rod 522 first,
control unit 510 comprises a block 524 having a bore 526 in which
rod 522 fits. A knob 528 can be rotated to advance rod 522 relative
to block 524. Optionally, a threaded rod 530 is provided for
rotation by knob 528, which rod 530 abuts and/or is axially coupled
to control rod 522.
[0218] Referring to the manipulation of control rod 520, a sleeve
538 is fit inside a bore 539 of block 524. A pin 532 (or other
means) locks the position of sleeve 538 to that of control rod 522.
A slot 534 and a slot 536 are optionally provided for allowing
motion of pin 532 with rod 522. Sleeve 538 includes an inner bore
542 in which rod 520 lies and also including a knob 540 and a
threaded rod 544 for adjustment of the position of rod 522 relative
to the position of sleeve 538.
[0219] As noted, tables 512 and 514 can also move in a Y direction,
optionally decoupled from "X" direction motion. In an exemplary
embodiment of the invention, rods 520 and 522 have a sliding
connection to the tables. In the example shown, rod 520 is attached
to a block 550 with a bore matching a perpendicular (e.g., in the
"Y" direction) rod 552. "Y" direction motion of table 512 will have
block 550 slide in a "Y" direction along rod 522, without affecting
an "X" direction effect of control unit 510. Table 514 can be
coupled to rod 522 by a block 546 with a perpendicular rod 548.
[0220] Adjustment along the axis of spindle 504 ("Z" direction") is
optional, and may be achieved using movable stops 506 and 508.
Optionally, such adjustment is provided to ensure that guide tube
402 will have clearance. Optionally, setting of drilling depth is
provided by setting such a "Z" position. Optionally, "Z" setting is
provided by placing a fitting on stop 506, to effectively increase
its axial thickness. Optionally, a fitting (or one of stops 508 and
508) is used to match an inner diameter of tube 402 to an outer
diameter of spindle 502. Alternatively, even if "Z" position is not
modified, knowledge of the "Z" position is used to determine an
insert for guiding tube 402 or other means of setting drilling
depth.
[0221] In a simplest implementation, guiding tube 402 is adjusted
by eye, e.g., using knobs 540 etc., until tube 402 is oriented
correctly. Optionally, feedback is provided from a display (e.g.,
on adjuster 500 or display 120, to show the effect of the
adjustment).
[0222] In another implementation, knobs 540, etc., include markings
to show their effect on the layout of tube 402. Optionally,
computer 126 is used to generate a set of values for a user to set
the knobs to (e.g., based on a table or a calculation that
translates a position and orientation to knob settings).
[0223] In another implementation, computer 126 directly sets knobs
540, etc., for example using stepper motors (not shown) controlled
via a connector (not shown). In a particular implementation, the
stepper motors are provided instead of rods 530 and 544. Knobs 528
and 540 may be used for further manual adjustment. Alternatively to
stepper motors, linear actuators may be used. Optionally, no
controller is provided, alternatively, an internal control may be
provided. Optionally, one or more sensors, for example optical
encoders (for example on the rods) are provided for reporting on
the relative and/or absolute positions of parts of adjuster 500.
Optionally, a user may still manipulate tube 402, for example to
prevent the computer controlled stepper motors from bending the
guiding section in a manner for which it was not designed or to try
out variations. One reason for manual adjustment of tube 02 and/or
the knobs is to allow a user to make changes, for example to
provide a more esthetic implantation location or angle or a
location better optimized for improved restoration.
[0224] In another implementation, the guiding section may include
one or more sensors that report on its joint positions. The
reported values may be used, for example for displaying feedback or
for feeding a computer controlled feedback loop used for
controlling the tube adjustment. Alternatively or additionally,
such sensors may be provided in adjuster 500, and may for example
provide feedback only on device 500 (e.g., if it includes a
display), or may be provided to computer 126.
[0225] It should be appreciated that the illustrated adjuster 500
is just one type of adjuster that can be used. In general, many
hexapod designs are known, many of which may be modified for use
with the present invention (e.g., modified to hold the guiding
section)
[0226] In an alternative adjuster design, guiding section 110 is
placed inside an outer sleeve and the outer sleeve is manipulated
to adjust each joint of section 110 separately.
[0227] Optionally, adjuster 500 is attached or adapted to be
attached (e.g., size and/or magnetic attraction) to a dental tool
tray.
[0228] Optionally, adjuster 500 includes a ruler for measuring the
length of the drill burr. In an exemplary embodiment of the
invention, a plain ruler is marked and a user enters the result
using user input 130. Alternatively, the resulting length may be
used to choose a matching drill length insert 450.
[0229] In an alternative embodiment of the invention, a
spring-based ruler is used. In one example, a bore 572 is formed in
adjuster 500. When a drill burr is inserted through an aperture 570
thereof, it presses against a spring 574. A marker 576 can indicate
the length on a suitable graded window.
[0230] In an exemplary embodiment of the invention, a pressure
sensor 578 senses the tension in the spring an generates a signal
indicative of the length. Other measuring methods may be used as
well.
[0231] As noted above, in some embodiments of the invention,
adjuster 500 applies heat, for example to melt glue in arm 110. In
an exemplary embodiment of the invention, heat is applied at
spindle 504 and base station 502. Such heat is optionally conducted
by metal parts of arm 110 (if a metal arm is used). Alternatively,
a heat lamp may be used. In an exemplary embodiment of the
invention, arm 110 is formed of a strip of heat-trainable material,
such as a shape memory material or a heat-softened plastic, which,
once heated above a training temperature, retains that shape, and
which interconnects base 302 and guide 402 (or serves as a joint).
In use, adjuster 500 is used to distort the strip. Optionally, the
strip is made thinner at the attachment to base 302 and tube 402.
Then, heat is applied to train the arm to its new
configuration.
[0232] In another embodiment, a goose-neck arm (such as used in
goose-neck lamps, but smaller) is used and adhesive is flowed
between the chinks of the goose-neck to lock the arm in a certain
configuration.
Self Mapping Guide
[0233] FIG. 6A is an isometric view of a pin-based dental
positioning device 600, in accordance with an exemplary embodiment
of the invention. This implementation is described in more detail
in U.S. Ser. No. 10/350,288. In general, two panels 602 and 604
each include a plurality of pins 606. In an exemplary embodiment of
the invention, each panel includes a two dimensional array of pins.
When pressed against hard tissue, the relative positions of the
pins indicate a topography of the hard tissue surface. In an
exemplary embodiment of the invention, the pins have associated
with each one an optical encoder 620 which reads a pin position
and/or movement from lines 622 engraved on the pin. Other read-out
methods are possible. In an alternative implementation, the pins
are locked in place and then the panel removed and read outside the
body. Optionally, the pins are arranged in modules which can be
removed without detaching device 600 from the jaw. Then, a tool may
be provided through a side panel to a desired location on the hard
tissue. A tool guide section is optionally mounted on a bridge 605
between the two panels. Optionally, one or both of panels 602 and
604 can be moved linearly (e.g., on a rail or along a screw) along
bridge 605 towards the other panel. In the implementation shown, an
air inlet 614 is used to provide pneumatic pressure to advance pins
606 through gum tissue and to a bone. Not described are elements
607, 616, 610, 618, 612 and 609 described in the above mentioned US
patent application.
[0234] In an exemplary embodiment of the invention, pins 606 are
used to acquire a surface image of the jawbone instead of using a
CT image.
[0235] In an alternative implementation, the pins give a bone
surface image which can be correlated or otherwise matched to a CT
image, so that a surface scanning is not required.
[0236] In another embodiment, a surface map acquired by pins is
combined with an x-ray image showing a mandibular canal on the
background of device, 600, giving a more or less complete
information useful for making dental decision.
[0237] While any of the guide sections described herein may be
used, In an exemplary embodiment of the invention, the guide
section comprises a hollow ball joint that is mounted on bridge
605, for example, if bridge 605 is a tube with an aperture at its
top. The ball can be rotated in one, two or three degrees of
orientation freedom, depending on the implementation. Optionally,
linear motion along the bridge is also allowed.
[0238] Optionally, one or more optical encoders are provided in the
bridge, for example to read position markings off of the ball and
indicate its orientation and/or position.
[0239] In an alternative implementation, the ball is replaced by a
tube axially positioned in the bridge tube (and which supports
rotation and/or axial motion) and a cylindrical joint which rotates
in a direction of the axis of the bridge tube. FIG. 6B shows an
exemplary such implementation. The reference numbers are described
in the above referenced US application by the applicant.
[0240] It should be noted that pins 606 can be used for surface
mapping also for other applications, in one example, pins 606 are
used to track bone loss. In another, the pins are used to track the
effect of bone enhancement (e.g., by periodic checking).
Optionally, a panel is also provided on the top of the implant. For
correlation purposes, possibly a single panel can suffice.
Side Mounted Guide
[0241] FIGS. 7A and 7B show a side schematic view and a top
schematic view of a side-mounted guide 706, in accordance with an
exemplary embodiment of the invention. In this design, a base
section 708 is mounted to a tooth 701 adjacent the treatment area.
A guiding section, for example section 110 described above, is
mounted on an extension 726 of base section 708, so that a base
portion 302 of section 110 is at approximately a same position
relative to the treatment area as in device 106.
[0242] Base section 708 includes a ring section 720 adapted to hold
tooth 701. For example, ring section 720 may comprise two band
parts 721 and 722 which can be attached by a lock 724, which
optionally applies tension and/or selectively shortens ring section
720. Many band (or other) mechanisms for holding teeth are known in
the art and may be used. Optionally, ring section 720 is thin
enough, at least at some parts thereof, so it can fit between two
teeth.
[0243] In an alternative implementation, ring section 720 is
elastic and can be held open to be placed around the tooth and then
released to close and lock tightly to the tooth. To this end, a
hole is optionally provided in each of band parts 721 and 722, to
serve as a force application point for a pliers like tool that
opens ring section 720.
[0244] Base plate 302 of guiding section 110 is optionally mounted
in a depression 704, for example, as provided for in FIG. 3.
[0245] It should be noted that the length of extension 726 (i.e.,
offset from tooth 701) maybe varied for various implanting
situations.
[0246] One potential advantage of the guide 706 is that there are
fewer elements in the mouth which might block a view or access to
the implant area.
Single Wing Guide and Other Guide Variations
[0247] FIG. 8A shows a tool guide 806 similar to guide 106, except
that only single wing 316 is provided. This may reduce interference
with view and/or access to the treatment area.
[0248] FIG. 8B shows a denture-based tool guide 810, in accordance
with an exemplary embodiment of the invention. In this
implementation, a denture like base section 812 is provided. this
has the potential advantage of being fixed to a relatively large
portion of a jaw, for example, 35% or more, so that a single
reference frame can be used for multiple treatments. In the example
shown, a wide work aperture 816 is provided. One or more tool guide
sections (not shown) optionally mount on one or more rails 814.
Optionally, the tool guide(s) can be moved along the rails, for
example from one position to a next position. Alternatively or
additionally, multiple tool guides are used together, for example
to setup simultaneous bores for two implant locations.
[0249] FIG. 8C shows a brace-based tool guide 830, in accordance
with an exemplary embodiment of the invention. A brace mounting
allows the tool guide to be coupled to bone not at the treatment
area. In the example, shown, a rail 832 contacts a lower jaw at a
rest 834, for example, a padded fork. An inner jaw extension 840
optionally engages the front of the jaw, from the inside. An
extension 836 optionally contacts the bottom of the jaw, at a
padded contact 838. A knob 842 is optionally provided for
controlling the length of rail 832. Typically, a pair of such
extensions and contacts is used, so that both sides of the jaw are
engaged at once. Other designs may be provided.
[0250] A tool guide is optionally mounted on rail 832 or on another
part of brace guide 830.
[0251] Other types of bases and attachment methods may be used as
well. In one example, the base has a layer of dental impression
material (such as Impregum). In another example, one or more
suction cups or adhesive areas are used to provide attachment. In
another example, base section 108 is adapted to attach to an
implant or to a temporary splint. In another example, base 108 is a
stent, for example formed by impression or other methods known in
the art, and including an attachment area.
[0252] For example, stent 106 can be a mass-produced item or a
customized item. For example, a customized brace or a customized
stent may be used. Alternatively, one or more standard sizes of
stents are provided (e.g., standard gap widths and standard
heights, for a dentist to select from.
Smart Guide
[0253] FIG. 9A shows a smart guide section 910, in which one or
more sensors are included to report on joint positions of the
guide, in accordance with an exemplary embodiment of the invention.
Such sensors can be incorporated in guide section 110, however, it
should be noted that guide section 910 also illustrates a simpler
design, with fewer degrees of freedom. Fewer degrees of freedom may
allow the use of fewer sensors and possibly lower cost.
[0254] In the embodiment shown, four degrees of freedom are
provided:
[0255] (a) a guiding tube 902 can be pivoted around a Y axis at a
tilt joint 920;
[0256] (b) tube 902 along with joint 920 can further be moved along
an X axis or rotated around the X axis at a joint 930; and
[0257] (c) joint 930 can be translated along a Y axis at a sliding
joint 940.
[0258] The design shown is tube 902 mounted on a rod 926, which rod
is movable in a box 928 having a tail section 934 and a bottom
section 936. In an exemplary embodiment of the invention, the one
or more of the following sensors are provided:
[0259] (a) a tilt sensor 922 reads a tilt of tube 902 relative to a
pin 924 which couples tube 902 to rod 926;
[0260] (b) an extension sensor 932 which measures an extension of
rod 926 relative to box 928;
[0261] (c) a rotation sensor 938 which measures a rotation of rod
926 around its axis; and
[0262] (d) a translation sensor 942 which measures translation of
bottom section 936 along joint 940, relative to a separate base
portion 950 with one or more rails 952.
[0263] The sensors can be, for example one or more of optical
sensors, magnetic sensors, capacitance sensors, piezoelectric
sensors and potentiometers. Various translation and rotation
methods and devices may be used as well, for example, linear and
rotational encoders or imaging detectors.
[0264] A potential disadvantage of guiding section 906 is that it
is flat and cannot bypass obstacles. Optionally, the base section
used is positioned so that depression 304 is at a plane or above a
plane of tissue at the implant area.
[0265] In operation, tilting and rotation of tube 902 set the
orientation of the bore of a drill. Translation of rod 926 and box
928 set the position of one point along the bore. Optionally, the
electronics for the sensors is in tail section 934. Optionally,
tail section 934 also includes a wired or wireless transmitter.
Alternatively, tail section 934 includes an indication of correct
positioning, for example a LED which lights when a current position
and/or orientation of tube 902 does not match a planned trajectory.
For example, tail section 934 may include a wired or wireless
receiver, or contacts for programming a desired orientation, and
one or more LEDs or other light sources on section 906 change their
illumination if the sensors are within a tolerance of their correct
orientation. Alternatively or additionally, computer 126 may attend
to reporting the position, for example as bore marking on display
120, or using an audio display.
[0266] In an exemplary embodiment of the invention, the sensors
used are optical encoders reading on optical encoding off of a part
of the joint. Many types of optical encoders which are suitable are
known, for example, fiber optic sensors with control electronics in
tail section 934 may be used. Alternatively, other, relative or
absolute sensors may be used. Optionally, box 928 serves to protect
some or all of the sensors from the environment.
[0267] FIG. 9B is a cross-sectional view of guide section 910,
showing locking and encoding details. In particular, a plurality of
line engraving reference areas 923 939 and 933 are shown
respectively for sensors 924, 938 and 932. Optionally, a rail 964
has marking 943 thereon for sensor 942. In an exemplary embodiment
of the invention, rail 964 (optional two are provided) is designed
to rigidly engages bases section 108.
[0268] An exemplary and optional locking mechanism is shown as
well. When a knob 980 is rotated, a threaded inner rod 962 is
pulled back, urging pin 924 towards knob 980. This increases
friction in guide section 910, locking it in place. Rotational and
axial locking is optionally provided by a screw (not shown) which
selectively engages rod 926 when rotated and is inserted, for
example, through the top of box 928 and perpendicular to rod
926.
Contact-Less Position Sensor Based Guiding
[0269] In the embodiments described above, sensors are provided in
the arm that moves. In alternative embodiments of the invention,
contact-less sensors are used. In an exemplary embodiment of the
invention, one sensor portion is provided on a base section and
another on the part whose position relative to the base needs to be
determined.
[0270] FIGS. 12 and 13 illustrate a contact-less sensing tool
guide, in accordance with an exemplary embodiment of the
invention.
[0271] FIG. 12 shows a sensor 1202 mounted on a stylus 1214. A
panel 1206 with markings 1208 is provided on the base section, for
example on a wing thereof, so that the signals generated by sensor
1202 relate to the relative position and/or orientation of sensor
1202 and panel 1206. Various sensor types may be used, for example,
sensor 1202 may be an imaging sensor. In another embodiment, sensor
1202 is a linear or scalar optical detector. Relative and absolute
sensors may be used. If a relative sensor is used (e.g., one which
detects motion), a zeroing step of moving the sensor to a known
"zero" position may be used to prevent accumulation of errors.
Optionally, sensor 1202 includes an illumination for panel 1206. In
an alternative embodiment, panel 1206 is self illuminated.
Alternatively, external or no illumination is provided.
[0272] Other types of sensors may be used, for example, magnetic
sensors or ultrasonic time of flight sensors. While generally not
desirable as it may reduce accuracy and be cumbersome, in an
exemplary embodiment of the invention, a magnetic field sensors is
used which measures an externally applied (e.g., from outside of
the mouth) magnetic field.
[0273] Optionally, a second (or more) sensors 1204 with a matching
panel 1210 and markings 1212, is provided.
[0274] Optionally, an inclination sensors 1214 is provided on the
base section and a second inclination sensor 1216 is provided on
stylus 1214, so that their relative inclinations may be determined.
It should be noted that for implant boring, the range of angles is
generally not very great, due to mechanical constraints of the
jaw.
[0275] FIG. 13 shows stylus 1214 mounted in a tool guide section
110 as described above, and which can be used to generate position
information while guide section 110 is being manipulated by stylus
1214. Optionally, this allows the stylus to be used as a user input
to control display 120. In an alternative embodiment, sensors 1202
and 1204 are mounted on tube 402 of guide section 110.
Alternatively, the sensors are mounted on a drill handle or a
handle for other dental tools.
[0276] Contact-less sensors may be used in various configurations.
In a first set of configurations, a guide arm 110 (or the like is
provided). If arm 110 is lockable, contacts-less sensors can be
operated much as other sensors. In an exemplary embodiment of the
invention, however, stylus 1214 is used to manipulate arm 110 and
once a correct positional and angular configuration is achieved,
guide arm 110 is locked, for example, using an electric current to
melt glue therein. This may be achieved, for example, under
computer control and optionally using a power source wholly
included in the tool guide, such as a battery. Optionally, this
allows arm 110 to be permanently fixed to the base section. It
should be noted that in such an application, longer sensor
integration times may be allowed, as real-time updating of display
120 may be less important. If guide arm 110 is not lockable,
sensors 1202 and 1204 may be used to provide real-time updating of
the position of arm 110 in space, as described above. It should be
noted that arm 110 can be made cheaper, as it can be made with no
sensors.
[0277] In a second set of configurations, no guide arm, per se, is
provided. instead, sensors 1202 and 1204 are used to detect a
position and/or orientation in space of stylus 1214 (or a tool or a
sleeve adapted to be mounted on a tool) relative to the base
section.
[0278] FIG. 14 illustrates an alternative contact-less sensing tool
guide 1400, in accordance with an exemplary embodiment of the
invention. In this embodiment, sensors 1402 and 1404 are mounted on
a base section 1409 of guide 1400, and panels 1406 and 1408 are
provided on tool guide section 110. As shown in this embodiment,
the markings can, for example, be two dimensional, so that each
sensor might provide 2 or 3 dimensions of information. Panels such
as panels 1406 and 1408 may also be provided on a sleeve, as
stickers, on a drill, on a dental tool or on a tool holder. As
described above, inclination sensors are optionally provided. As
described above, illumination is optionally provided.
[0279] While the sensors are optionally provided calibrated to the
markings, optionally a calibration procedure can be used, for
example, contacting stylus 1214 to one or more predefined points on
the stent. Optionally, a form is provided that fits in the stents,
so that an orientation of stylus 1214 can also be controlled, for
example, as shown in FIG. 11, but not blocking the field of view of
the sensors.
[0280] Similarly to guide section 108, contact-less sensors may be
used in adjuster 500, to report on the position of guide tube 402.
Optionally, adjuster 500 will include in such a case only a heating
element for fixing guide arm 110 in place, rather than the knob and
x-y table arrangement described.
X-ray Registration Guide
[0281] In an exemplary embodiment of the invention, 2D x-ray
transmission images are used for registering the tool guide to a
known jaw geometry (e.g., a geometry provided by a CT image). FIG.
10 shows a tool guide 1006 including an x-ray opaque grid 1008, in
accordance with an exemplary embodiment of the invention. The rest
of guide 1006 can be transparent to x-ray, for example being made
of plastic, and optionally transparent to light, at least in some
parts thereof. The grid can be, for example, lines of a known
length and/or one or more crosses.
[0282] In use, two linear grids are provided on either side of the
jaw (e.g., grid 1008 and a grid 1014, not visible), and an image is
acquired through the jaw and the tool guide, for example using a
reusable or non-reusable x-ray plate 1010. Plate 1010 is optionally
attached to one side of guide 1006, for example using an attaching
and/or aligning element 1016. Optionally, guide 1006 includes an
x-ray plate holder. Optionally, an external aiming element is
attached or attachable to guide 1006, and includes an extension out
of a mouth and including a ring or other target at its end for
aiming an x-ray tube. In the resulting images, the grids show the
layout of guide 1006 relative to the jaw structures, in a certain
projection direction. The relationship between the two grids
indicates the direction.
[0283] In an alternative embodiment of the invention, one of the
opaque grids, for example a grid 1012 is provided on plate
1010.
[0284] In an alternative use, such a grid is used instead of one or
more CT images. For example, such a grid can indicate a relative
depth to a mandibular canal.
[0285] If a pin based device as shown in FIG. 6 is used, a complete
data set may be obtained. The pins provide a surface image and the
x-ray grid shows an allowed depth (to the mandibular canal). This
data is good enough to generate a cross-section view of area 104,
in which the possibilities of drilling a bore are shown.
[0286] Alternatively to plain x-ray images, more complex images,
such as panoramic, and periapical x-ray images may be used.
Optionally, the grids are used as an aiming tool, in which a user
can pierce plate 1010 to reach the desired treatment area through
the body of guide 1006. Guide 1006 may have a soft section or an
aperture or a removable cover (e.g., removing pin modules from the
embodiment of FIG. 6) to prevent damage and/or dislodgment of guide
1006.
Fabricated Guide
[0287] FIG. 11 shows a tool guide 1100, having a custom fabricated
guide section 1104 adapted to mount on a standard base section
1102, in accordance with an exemplary embodiment of the
invention.
[0288] In the example shown, guide section 1104 comprises a block
of material in which a bore 1108 has been drilled, to achieve a
desired drilling direction. In an exemplary embodiment of the
invention, an insert 450 is provided, for example, to prevent
damage to guide section 1104 by a drill burr 1110 and/or to adapt
its diameter and/or a drilling depth.
[0289] In the embodiment shown, one or more spring clamps 1106 is
used to hold guide section 1104 in place.
[0290] In an exemplary embodiment of the invention, guide section
1104 is fabricated in the following manner. A block of solid
material, such as plastic, is placed on an X-Y table and is moved
relative to a drill, for example, under manual or computer control.
The drill is then powered and advanced to drill through the block,
for example using a drill-press. Optionally, the drill is mounted
on gimbals to control its orientation. Alternatively, the X-Y table
is so mounted. In one example, a hexapod structure, of which many
are known in the art for three dimensional positioning, is used.
Other positioning and orientating methods described herein or known
in the art may be used instead of an X-Y table, for example, an
articulated arm. In one example, a positioning system as described
herein is used to control or display the position and orientation
of a dental drill of a large bore, which drill is used for drill
1110.
[0291] It will be appreciated that the above described methods of
bone surface measurement and tool guiding may be varied in many
ways, including, changing the order of steps and the types of tools
used. In addition, a multiplicity of various features, both of
method and of devices have been described. In some embodiments
mainly methods are described, however, also apparatus adapted for
performing the methods are considered to be within the scope of the
invention. It should be appreciated that different features may be
combined in different ways. In particular, not all the features
shown above in a particular embodiment are necessary in every
similar embodiment of the invention. Further, combinations of the
above features are also considered to be within the scope of some
embodiments of the invention. Also within the scope of the
invention are surgical kits which include sets of medical devices
suitable for performing a single or a small number of measurements,
tool guiding and/or implantation. Also, within the scope is
hardware, software and computer readable-media including such
software which is used for carrying out and/or guiding the steps
described herein, such as surface matching and bore selection.
Section headings are provided for assistance in navigation and
should not be considered as necessarily limiting the contents of
the section. When used in the following claims, the terms
"comprises", "includes", "have" and their conjugates mean
"including but not limited to".
[0292] It will be appreciated by a person skilled in the art that
the present invention is not limited by what has thus far been
described. Rather, the scope of the present invention is limited
only by the following claims.
* * * * *
References