U.S. patent number RE44,509 [Application Number 10/436,806] was granted by the patent office on 2013-09-24 for surgical needle.
This patent grant is currently assigned to Inter-Med, Inc.. The grantee listed for this patent is Gary J. Pond. Invention is credited to Gary J. Pond.
United States Patent |
RE44,509 |
Pond |
September 24, 2013 |
Surgical needle
Abstract
An autoclavable needle assembly and method of making the same is
provided for endodontic surgical procedures. The needle assembly
includes a supporting hub member containing an adhesive in which
one end of the needle is embedded. The surgical needle is
preferably fabricated from NiTi alloy and includes, at its distal
end, a side vent in the form of a skived portion extending a
predetermined distance inwardly from the tip from the distal end of
the needle. One or more coatings may be applied to the needle. An
angle-adjustment sleeve can be bent to hold a desired angle in the
needle.
Inventors: |
Pond; Gary J. (Racine, WI) |
Applicant: |
Name |
City |
State |
Country |
Type |
Pond; Gary J. |
Racine |
WI |
US |
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Assignee: |
Inter-Med, Inc. (Racine,
WI)
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Family
ID: |
23729274 |
Appl.
No.: |
10/436,806 |
Filed: |
May 13, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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09435658 |
Nov 8, 1999 |
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Reissue of: |
09654201 |
Sep 1, 2000 |
6494713 |
Dec 17, 2002 |
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Current U.S.
Class: |
433/81;
433/224 |
Current CPC
Class: |
A61C
5/40 (20170201); A61M 5/158 (20130101); A61C
17/02 (20130101) |
Current International
Class: |
A61C
1/00 (20060101) |
Field of
Search: |
;433/81,224,80,91
;604/239,240,241,242,243,264,272,273,274,150,160,154.01,166.01
;606/167,170,185 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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0 294 210 |
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Dec 1988 |
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EP |
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0 440 948 |
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Aug 1991 |
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EP |
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0 604 062 |
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Jun 1994 |
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EP |
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0 604 062 |
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Jun 1994 |
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EP |
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0 440 948 |
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Aug 1995 |
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EP |
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0 529 675 |
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Feb 1996 |
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EP |
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0 696 213 |
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Feb 1996 |
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EP |
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08103456 |
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Apr 1996 |
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JP |
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Other References
Article "Parylene Conformal Coatings Specifications and Properties"
Date Nov. 1998 Specialty Coating Systems. cited by applicant .
Article "Parylene Confornal Coatings Specifications and Properties"
Date: Nov. 19, 1998 Specialty Coating Systems. cited by
applicant.
|
Primary Examiner: Lewis; Ralph
Attorney, Agent or Firm: Ryan Kromholz & Manion,
S.C.
Parent Case Text
This application claims the benefit of and is a
continuation-in-part of copending U.S. patent application Ser. No.
09/435,658 filed on Nov. 8, 1999, now abandoned.
Claims
What is claimed is:
.[.1. A surgical needle assembly for endodontic procedures, said
assembly comprising: a needle having one end encapsulated and
grippingly supported by a hub member and including a coextensive
bore; said needle further including a protruding hollow shaft
portion of predetermined length; an angle-adjustment sleeve
surrounding a portion of said needle; the distal end of said needle
including an arcuate longitudinal skived portion having an arcuate
height of a predetermined proportional ratio relative to the
diameter of said bore..].
.[.2. The needle assembly of claim 1, wherein the angle-adjustment
sleeve is formed from an annealed stainless steel..].
.[.3. The needle assembly of claim 1, wherein the angle-adjustment
sleeve is secured to said hub member..].
.[.4. The needle assembly of claim 1, wherein the angle-adjustment
sleeve is adhesively secured to said hub member..].
.[.5. The needle assembly of claim 1, wherein the angle-adjustment
sleeve is secured to said needle using a pressure stressed
connection..].
.[.6. The needle assembly of claim 1, wherein the angle-adjustment
sleeve surrounds approximately one-third of the needle protruding
hollow shaft portion..].
7. A method of fabricating a surgical needle assembly for
endodontic procedures including the steps of: providing a tubular
shaft; die cutting said shaft to provide a surgical needle of
predetermined length.Iadd., said needle having a first end and a
second end.Iaddend.; .[.machining one end of said needle to provide
a skived portion of predetermined length;.]. providing a hub member
having a cup-like interior; supplying an autoclavable adhesive to
the cup-like interior of said hub member; and inserting .[.the
opposite.]. .Iadd.said first .Iaddend.end .Iadd.of said needle
.Iaddend.in said adhesive for retention and support thereof by said
hub member; providing an angle-adjustment sleeve; placing said
angle-adjustment sleeve over the needle and into said adhesive for
retention and support thereof by said hub member.
8. A method of fabricating a surgical needle assembly for
endodontic procedures including the steps of: providing a tubular
shaft; die cutting said shaft to provide a surgical needle of
predetermined length.Iadd., said needle having a first end and a
second end.Iaddend.; .[.machining one end of said needle to provide
a skived portion of predetermined length;.]. providing a hub member
having a cup-like interior; supplying an autoclavable adhesive to
the cup-like .[.interior-of.]. .Iadd.interior of .Iaddend.said hub
member; and inserting .[.the opposite.]. .Iadd.said first
.Iaddend.end .Iadd.of said needle .Iaddend.in said adhesive for
retention and support thereof by said hub member; providing an
angle-adjustment sleeve; positioning said angle-adjustment sleeve
over said needle; forming a pressure stressed connection between
said angle-adjustment .Iadd.sleeve .Iaddend.and said needle by
deforming said angle-adjustment sleeve.
.Iadd.9. The method of claim 7, further including the step of
machining said second end of said needle to provide a skived
portion of predetermined length..Iaddend.
.Iadd.10. The method of claim 8, further including the step of
machining said second end of said needle to provide a skived
portion of predetermined length..Iaddend.
.Iadd.11. The method of claim 7, wherein the needle comprises a
nickel titanium alloy..Iaddend.
Description
BACKGROUND OF THE INVENTION
This invention relates to surgical needles, and in particular,
needles used for endodontic procedures, such as root canal surgery.
During endodontic procedures, such as root canals, it is necessary
to inject or applicate fluid into the dental pulp or root.
Presently, typical needles used for these types of procedures are
made from relatively inflexible stainless steel. This material has
been preferred for its ability to be autoclaved and its relatively
inexpensive cost; however, use over time in endodontic applications
has revealed several undesirable characteristics. For example, a
typical tooth has at least one root. Each root is not straight, but
curves toward the centerline of the tooth. The relative rigidity of
stainless steel has led to unwanted results when used in root canal
surgery due to the needle's inability to bend to the contour of the
curved root canal. During a root canal procedure, a dental
practitioner drills an opening in a patient's tooth surface enamel
and inner dentine to gain access to the dental pulp and surrounding
cavity. A hollow, stainless steel surgical needle is inserted into
the opening to remove decaying pulp tissue and irrigate the
surrounding cavity with sodium hypochlorite solution. The sodium
hypochlorite solution rids the canal of bacteria and other foreign
substances before sealant is injected into the canal. The dental
pulp cavity is curvately elongate and tapers into the root area of
the affected tooth. The rigid nature of a stainless steel needle
does not allow the flexion necessary to move through the delicately
curved root cavity to reach the most distal end. At present, the
dental practitioner must exert extreme care in using the stainless
steel needle to avoid puncture of the tooth wall and surrounding
jaw. Common dental practice at this time is to pre-bend the needle
prior to insertion using an X-ray image as a template. Although
pre-bending allows the dental practitioner to insert the needle
into the root canal somewhat farther than when the needle is left
straight, this method is crude at best and full access to the root
canal apex cannot be achieved. Should the dental practitioner meet
needle resistance during insertion, he must discontinue insertion
or risk damage of the tooth and surrounding area. If this occurs,
the practitioner must be satisfied with partial depth insertion and
subsequent partial irrigation. The tip of the root cannot be
accessed so completely so full aspiration and irrigation cannot be
accomplished. If the dental practitioner continues insertion after
meeting curvature resistance, the risk of punching a hole in the
tooth wall becomes great.
The practice of using endodontic surgical needles fabricated from
nickel titanium (NiTi) stainless steel is known under the teachings
of U.S. Pat. No. 5,000,912 issued to Bendel et al among others, in
addition to other nickel titanium alloys disclosed in U.S. Pat.
Nos. 4,337,000; 4,565,589; 4,505,767; 4,770,725 and European Patent
EP 0 529 675 B1, also granted to Bendel et al. The use of this
alloy in connection with conventional endodontic needles has not
achieved desired results. The present invention contemplates
fabrication of endodontic surgical needles of an alloy of nickel
and titanium, per se, including a stainless steel sleeve to allow
for manual fixed-angle adjustments in the upper portion of the
needle, and a modification of the distal end of the needle to
provide a skived, side-vented area.
SUMMARY OF THE INVENTION
It is therefore an object of this invention to provide an
autoclavable endodontic needle assembly capable of curving to the
configuration of a root canal while being inserted therein. The
needle is preferably fabricated from a binary NiTi alloy. The
preferred binary NiTi alloy contains 55.8 weight percent Nickel.
The needle of the present invention may be produced to be pre-bent
to a desired angle; the preferred angle chosen is 45 degrees. The
present invention may also include an angle-adjustment sleeve
around a portion of the needle to allow for manual adjustment of
the pre-bent angle. An adhesive-filled supporting hub member
grippingly engages the needle shaft to provide connection to a
conventional luer lock. The supporting hub configuration may also
be pre-bent to a desired angle, such as 45 degrees, with the
protruding needle shaft being straight. The options of straight or
pre-angled needle, straight or pre-angled hub portion, and manually
adjustable angling sleeve are conceived to give the dental
practitioner convenient options for ease of use while working
within the awkward confines of a patient's mouth.
Sodium hypochlorite solution, depending upon the solution strength,
can be a caustic solution and may have an adverse affect on the
preferred binary NiTi alloy. To substantially eliminate the
possibility of the solution corroding or deteriorating the NiTi
alloy, a coating, such as a parylene polymer, is applied to the
needle during its manufacture. While parylene polymers are the
preferred coatings, there are other commercially available coatings
that provide the same protection. The coating prevents the sodium
hypochlorite solution from adversely affecting the physical
properties of the dental needle.
It is a further object of the present invention to provide a unique
tip for the needle. The tip portion of the present invention
includes a skived area at the most distal end of the needle. The
skived area allows side venting of irrigation fluid and prevents
vacuum build up during aspiration of the root canal. The unique tip
is further capable of functioning within the narrow and curved
confines of a root canal.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a longitudinal cross sectional view of a tooth and its
normal environment and showing a prior art endodontic needle
disposed therein during said procedure.
FIG. 2 is a longitudinal cross sectional view of a tooth and its
normal environment and showing a prior art endodontic needle
disposed therein during said procedure.
FIG. 3 is a longitudinal cross section the improved needle of the
present invention disposed within the tooth cavity.
FIG. 4 is an elevational view of the needle and supporting device
of the present invention.
FIG. 4a is an elevational view similar to the view of FIG. 4, and
illustrating an alternate needle and supporting device but with the
needle being bent to a predetermined angle.
FIG. 5 is a cross sectional view taken along lines 5-5 of FIG.
4.
FIG. 6 is an elevational view of the present invention showing a
hydrophobic layer coated on the exterior surface of the supported
needle.
FIG. 7 is a cross sectional view taken along line 7-7 of FIG.
6.
FIG. 8 is a perspective view of the distal end portion of the
coated shaft of the surgical needle made according to the present
invention.
FIG. 9 illustrates a conventional luer connector modified to
include a bend intermediate its ends and arranged to receive and
secure the surgical needle as shown in preceding figures.
FIG. 10 is a sectional view taken along lines 10-10 of FIG. 9.
FIG. 11 is an elevational view of the needle, angle-adjustment
sleeve and supporting device of the present invention.
FIG. 12 is an elevational view similar to the view of FIG. 11, and
illustrating the angle-adjustment sleeve bent to a desired angle of
approximately 45 degrees.
FIG. 13 is an elevational view similar to the view of FIG. 11, and
illustrating the angle-adjustment sleeve bent to a desired angle of
approximately 70 degrees.
FIG. 14 is a fragmentary perspective view of the present invention,
wherein the angle-adjustment sleeve is secured using an
adhesive.
FIG. 15 is a fragmentary perspective view of an alternative
embodiment of the present invention, wherein the angle-adjustment
sleeve is secured using a pressure stressed connection.
FIG. 16 is a fragmentary perspective view of an alternative
embodiment of the present invention, wherein the angle-adjustment
sleeve is secured using a pressure stressed connection
DETAILED DESCRIPTION
Although the disclosure hereof is detailed and exact to enable
those skilled in the art to practice the invention, the physical
embodiments herein disclosed merely exemplify the invention which
may be embodied in other specific structure. While the preferred
embodiment has been described, the details may be changed without
departing from the invention, which is defined by the claims.
FIGS. 1 and 2 illustrate a prior art dental needle 10' used for
endodontic procedures. Needles of this type have been made of
relatively rigid stainless steel. This rigidity has created
difficulty for the dental practitioner due to their inability to
flex and conform to the contours of a typical root canal. As seen
in FIG. 1, the prior art needle 10' may puncture the root canal
wall 12 if undue pressure is exerted in an attempt to insert the
needle 10' farther into a tooth 14 than its capability to flex.
FIG. 2 illustrates the prior art needle 10' as inserted to its
maximum depth, without puncture of the root canal wall 12; however,
the needle 10' is unable to reach the apical constrictive terminus
16 of the root canal 18 of tooth 14. Partial insertion of the
needle 10' results in incomplete irrigation and aspiration of the
root canal 18 and prevents the complete removal of decay and dental
pulp material required in a successful root canal procedure.
Referring to FIG. 3, the needle 10 of the present invention is
shown. The needle 10 conforms to the curved contour of the root
canal 18 and is thus able to reach the apical constrictive terminus
16 of the root 18 without interruption or diametral confinement.
Further, the modified tip 20 allows side venting, thereby reducing
undue vacuum and pressure during aspiration and irrigation.
As seen in FIG. 4, a preferred embodiment of the needle 10 of the
present invention is shown. The needle 10 is preferably mounted in
a hub member or apparatus 22. The hub apparatus 22 is preferably
provided with a cup-like interior and further includes a
conventional LUER.RTM. connector 24. The connector 24 is also
commonly referred to as a slip LUER.RTM. or a LUER.RTM. lock
fitting. The hub apparatus 22 is molded from autoclavable material,
such as Ultim 1000, obtainable from General Electric Corporation.
The total needle shaft length, (L) may be of any useful length,
although the preferred length is 32.26 mm. A portion of the total
shaft length (L'), shown in phantom, is it grippingly supported by
the hub portion 22. The shaft length (L') is secured to the hub
portion 22 with an adhesive (not shown) capable of withstanding
autoclavable temperatures as for instance, 135.degree. C. An
example adhesive is part number 302-3M, obtained from Epoxy
Technology of Billerica, Mass. The length of the supported portion
(L') may be of any practical length, but in the present embodiment
is preferably 7 mm. The shaft length (L) is further portioned into
a distal end skived portion 20 which, in the preferred embodiment
is 1/25 of the needle shaft portion (L) minus the length of the
supported portion (L'). In the preferred embodiment (see also FIG.
8), this ratio calculated results in a skived portion length (1) of
approximately 1 mm.
FIG. 4a illustrates an alternate embodiment needle 10 wherein the
needle shaft length (L) is pre-bent for ease of use. Although the
shaft length (L) could be pre-bent to any convenient angle, the
preferred angle is approximately 45 degrees.
As seen in FIGS. 5 and 7, a cross section of the modified tip 20
shows the skived portion 26 having an arcuate height (d) of
approximately 2/3 the diameter (D) of the needle bore 28. In the
preferred embodiment, the diameter (D) of the needle bore 28 is
approximately 0.3 mm, although it is to be understood that a
greater or lesser bore diameter may also be employed.
Another embodiment of the present invention is seen in FIGS. 6 and
7. The needle 10 may be provided with a coating 30 to prevent the
possibility of corrosion or deterioration of the needle 10 when
exposed to a caustic solution such as sodium hypochlorite. One such
acceptable coating 30 is a parylene polymer. Parylene polymers have
a very low permeability to moisture and other corrosive gases and
fluids. A substantially pin hole free coating can be applied to the
exposed metallic surfaces of the NiTi needle 10. It has been found
that the coating 30 is most effective in the thickness range of 0.1
to 2.0 microns. Parylenes resist room temperature chemical attack
and are insoluble in all organic solvents up to 150 degrees
Celsius. The polymer is also resistant to permeation by solvents.
The ability to deposit parylene as a truly conformal, thin,
continuous uniform adherent coating permits enhances its
application to the needle 10.
In addition or in lieu of the polymer coating, the needle 10 may be
provided with a hydrophobic lubricant 30 to aid in smooth and fluid
insertion into the tooth (not shown in this view). The hydrophobic
lubricant 30 also helps prevent residual tissue from re-adhering to
itself during aspiration.
With reference to FIGS. 9 and 10, it will be observed that the
supporting hub portion 22, itself, may be bent to a predetermined
angle, which may be 45.degree.. When the hub portion 22 is bent the
needle 10 to be utilized is preferably straight.
As depicted in FIGS. 11 through 13, inclusive, the present
invention may also include an angle-adjustment sleeve 34 for
manually pre-bending the needle 10. The adjustment sleeve 34 is
preferably made from a fairly rigid material capable of holding the
needle 10 at a desired angle, while at the same time being pliable
enough to allow for quick adjustment without using tools. It must
not kink or bend sharply, but must curve gradually without pinching
or compressing the needle 10. The adjustment sleeve 34 may be of
any suitable length to hold a desired angle in a desired portion of
the needle 10, may be positioned anywhere along the length of the
needle 10, and may extend from inside the hub member 22. In the
preferred embodiment, the sleeve 34 is made from an annealed
stainless steel. It begins just inside the hub member 22 and
extends approximately one-third of the exposed length "L" of the
needle 10.
The adjustment sleeve 34 may be attached to the needle 10, hub
member 22, or both in any conventional fashion. Referring to FIG.
14, a method of securing the sleeve 34 includes using an adhesive
36 capable of withstanding autoclavable temperatures as described
above, which may or may not be the same adhesive used to secure the
needle 10 to the hub member 22. In the preferred embodiment, the
adhesive 36 is used to secure, the sleeve 34 to both the hub member
22 and the needle 10.
Referring to FIGS. 15 and 16, an alternative embodiment of the
present invention is depicted, wherein the adjustment sleeve 34 may
be secured to the needle with a pressure stressed connection 38.
The connection 38 is a deformation in the sleeve 34, such as a
crimped or swaged connection, that prevents the sleeve 34 from
moving relative to the needle 10. Although the connection 38
secures the sleeve 34 tightly, it does not cause a notable
deformation in the needle 10, or prevent dental material from
passing through the needle 10. The stressed connection 38 may be
made at any location along the length of the sleeve 34, and two
included locations are depicted in FIGS. 15 and 16.
The foregoing is considered as illustrative only of the principles
of the invention. Furthermore, since numerous modifications and
changes will readily occur to those skilled in the art, it is not
desired to limit the invention to the exact construction and
operation shown and described. While the preferred embodiment has
been described, the details may be changed without departing from
the invention, which is defined by the claims.
* * * * *