U.S. patent application number 09/838681 was filed with the patent office on 2002-10-24 for anatomically shaped sectional matrix band retainers.
Invention is credited to Bills, Dan J..
Application Number | 20020155410 09/838681 |
Document ID | / |
Family ID | 25277787 |
Filed Date | 2002-10-24 |
United States Patent
Application |
20020155410 |
Kind Code |
A1 |
Bills, Dan J. |
October 24, 2002 |
Anatomically shaped sectional matrix band retainers
Abstract
The invention comprises improved matrix band retainers for use
in dental procedures. The matrix band retainers comprise a pair of
tines that are anatomically configured to be inserted into the
interproximal spaces between teeth for holding a matrix band in
proper alignment during a dental filling procedure and for keeping
the matrix band retainer from slipping out of position. The tines
may be curved and/or include a wedge-shaped portion to facilitate
insertion of the tines into the interproximal spaces between two
adjacent teeth. The matrix band retainers also comprise two
apertures that are configured in size and shape to receive the
prongs of a rubber dam clamp or other tine-spreading device for
enabling the rubber dam clamp to spread the tines of the matrix
band retainer in a safe and secure manner.
Inventors: |
Bills, Dan J.; (Salt Lake
City, UT) |
Correspondence
Address: |
WORKMAN NYDEGGER & SEELEY
1000 EAGLE GATE TOWER
60 EAST SOUTH TEMPLE
SALT LAKE CITY
UT
84111
US
|
Family ID: |
25277787 |
Appl. No.: |
09/838681 |
Filed: |
April 19, 2001 |
Current U.S.
Class: |
433/153 ;
433/139; 433/155 |
Current CPC
Class: |
A61C 5/85 20170201 |
Class at
Publication: |
433/153 ;
433/155; 433/139 |
International
Class: |
A61C 005/04; A61C
003/00 |
Claims
What is claimed and desired to be secured by United States Letters
Patent is:
1. An apparatus for retaining a matrix band against a tooth
comprising: a flexible member, and first and second tines connected
by the flexible member, wherein each of said first and second tines
comprises at least one of a curved body or a wedge-shaped body in
order to facilitate retention of a matrix band within the
interproximal spaces between a pair of adjacent teeth.
2. An apparatus as defined in claim 1, wherein each of said first
and second tines comprises a curved body, said body extending
between a proximal end and a distal end.
3. An apparatus as defined in claim 1, wherein each of said first
and second tines comprises a wedge-shaped body having an angled
edge portion that is oriented so as to be inserted into the
interproximal spaces between the pair of adjacent teeth, said
angled edge portion having an angle in the range of about
30.degree. to about 90.degree..
4. An apparatus as defined in claim 3, wherein the wedge-shaped
body comprises a substantially triangular cross-sectional area.
5. An apparatus as defined in claim 1, wherein the flexible member
comprises two apertures extending therethrough, and wherein each of
said apertures is configured to receive a prong of a tool that is
used to bend the flexible member, such that the tool spreads the
first and second tines apart.
6. An apparatus as defined in claim 5, wherein said tool is a
rubber dam clamp.
7. An apparatus as defined in claim 1, wherein the flexible member
comprises stainless spring steel.
8. An apparatus as defined in claim 1, wherein the distal end of at
least one of either said first and second tines further comprises a
foot.
9. An apparatus as defined in claim 8, wherein the foot protrudes
away from the at least one of either the first and second tines
towards the distal end of the other of the first or second
tines.
10. An apparatus as defined in claim 1, wherein the flexible member
comprises an arcuate member.
11. An apparatus as defined in claim 2, wherein said first and
second tines are positioned substantially perpendicular to the
flexible member.
12. An apparatus for retaining a matrix band against a tooth
comprising: a flexible member interconnecting a first tine and a
second tine, each of said first and second tines comprising a
wedge-shaped body having an acutely-angled edge portion oriented so
as to facilitate insertion of the wedge-shaped body into
interproximal spaces between two adjacent teeth.
13. An apparatus as defined in claim 12, wherein each tine is
further curved so as to more closely approximate the anatomy of the
two adjacent teeth.
14. An apparatus as defined in claim 12, wherein said flexible
member comprises two apertures extending through the flexible
member, and wherein each of said two apertures is configured to
receive a prong of a tool that is used bend the flexible member to
increase a distance separating the first tine from the second
tine.
15. An apparatus as defined in claim 12, wherein the acutely-angled
portion has an angle in a range of about 30.degree. to about
90.degree..
16. An apparatus for retaining a matrix band against a tooth
comprising: a flexible member; first and second tines extending
from the flexible member, each of said tines including: a proximal
end connected to the flexible member; a distal end opposite the
proximal end; and a curved body extending between the proximal and
distal ends, said curved body being sized and shaped to
approximately conform to the shape of interproximal spaces between
two adjacent teeth.
17. An apparatus as defined in claim 16, wherein the curved body of
each of said first and second tines further includes a wedge-shaped
cross-sectional area oriented to facilitate insertion of the curved
body into the interproximal spaces.
18. An apparatus as defined in claim 17, wherein the wedge-shaped
cross-sectional area includes an angled edge having an angle in a
range of about 30.degree. to about 90.degree..
19. An apparatus as defined in claim 16, wherein said flexible
member comprises two apertures extending through the flexible
member spaced and configured so as to receive corresponding prongs
of a tine-spreading device.
20. An apparatus as defined in claim 19, wherein the tine-spreading
device is a rubber dam clamp.
Description
BACKGROUND OF THE INVENTION
[0001] 1. The Field of the Invention
[0002] The present invention is in the field of matrix band
retainers for use in dental procedures. In particular, the present
invention relates to matrix band retainers that are configured to
be inserted into the interproximal spaces between teeth to hold a
matrix band in proper placement during dental filling procedures.
More particularly, the matrix band retainers of the present
invention are preferably anatomically configured to conform to the
shape of teeth.
[0003] 2. The Prior State of the Art
[0004] In the field of dentistry, dental practitioners often treat
patients who have developed cavities in a tooth. In order to treat
cavities the dental practitioner removes the infected portion of
the tooth and then deposits a filling material such as a composite,
a resinous material, or an amalgam into the tooth preparation.
[0005] During the dental filling procedure, a matrix band is
typically placed against the side of the tooth to approximately
define the desired shape of the restored tooth and to keep the
filling material from flowing beyond the desired tooth boundary. A
matrix band typically comprises a thin metallic or plastic strip
that is flexible and can be bent around the tooth being restored.
The matrix band is particularly useful because it provides form for
the desired shape of the resultant filling. However, if the matrix
band is not properly held in place then too much or too little
filling material may be deposited into the tooth preparation,
thereby distorting the configuration of the restored tooth.
[0006] An improper filling can lead to dental discomfort,
misaligned teeth, capture of food particles, infections, and other
dental problems. To avoid these problems and to fix a distorted
dental filling, it may be necessary to grind or drill the filling
material down to the proper shape. It is desirable, however, to
avoid this process because it increases the time and cost of
performing the filling procedure and can create anxiety and
discomfort for the patient.
[0007] In order to place the matrix band into a desired placement,
it is sometimes necessary to separate the teeth by placing small
dental wedges in the interproximal spaces between the teeth. One
inherent problem with the use of matrix bands and dental wedges,
however, is that they are susceptible to moving and slipping out
from between the teeth. In an attempt to avoid this problem, dental
practitioners have used clamps, commonly known as matrix band
retainers, to hold the matrix band and dental wedges in place
during the filling procedure.
[0008] Conventional matrix band retainers consist of a rigid,
cylindrical wire bent so as to have a generally circular body and
one of two generally straight tines extending perpendicularly from
each end of the circular body. During use, the tines are spread
open and placed in the interproximal spaces between the tooth being
repaired and an adjacent tooth. One problem with such matrix band
retainers is that the tines do not anatomically conform to the
shape of the teeth. This results in inadequate retention of the
matrix band such that the matrix band in an anatomically correct
conformation. In addition, such matrix bands can easily slip out of
position.
[0009] Another problem concerns the initial placement of the
conventional matrix band retainer. The flexible frame or body of
conventional matrix band retainers is typically a rigid,
cylindrical wire that has been bent to have a generally circular
configuration. The rigidity of the wire helps create a strong,
spring-like action. It also, however, makes it difficult to spread
the tines apart by hand.
[0010] To provide additional leverage to spread the tines apart,
conventional rubber dam clamps may be used to spread the tines by
flexing or bending the flexible frame or body of the matrix band
retainer. Although rubber dam clamps can be used to spread the
tines apart, existing matrix band retainers are not specifically
configured to receive the prongs of the rubber dam clamp.
Accordingly, the use of a rubber dam clamp to spread the tines can
be unsafe. For example, it has been found that the matrix band
retainer can slip off the prongs of the rubber dam clamp, making
the procedure both difficult and unsafe.
[0011] Accordingly, there is currently a need in the art for
improved matrix band retainers that are configured to better fit
within the interproximal spaces between teeth so as to better hold
matrix bands in desired and proper placement during dental
procedures. It would also be desirable to provide improved matrix
band retainers that are specifically configured to more securely
and reliably receive the prongs of a conventional rubber dam clamp
or other spreading tool. Such improved matrix band retainers are
disclosed and claimed herein.
SUMMARY OF THE INVENTION
[0012] The present invention is directed to improved matrix band
retainers for use in dental filling procedures. The matrix band
retainers of the invention comprise tines that are anatomically
configured in size and shape to better fit within the interproximal
spaces between teeth for providing increased contact with the
surfaces against which the matrix band retainer is placed. Such
matrix bands are better able to retain a matrix band in an
anatomically correct configuration during a dental filling
procedure. The matrix band retainers of the invention are also
specifically configured to more securely receive the prongs of a
rubber dam clamp for spreading the tines of the matrix band
retainer in a safe and secure manner.
[0013] In one preferred embodiment of the invention, the matrix
band retainer comprises two tines that are connected to an arcuate
member comprising stainless spring steel. Each tine comprises a
curved and/or wedge-shaped body that is anatomically configured to
be inserted into the interproximal spaces between teeth.
[0014] In a first embodiment, the tines are curved so as to
approximate the curvature of teeth, typically molars or bicuspids.
In this manner, each tine provides an anatomical bearing surface
that urges the matrix band to better conform to the shape of the
tooth being restored, particularly, the outer curved surface of the
tooth.
[0015] In the same or alternative embodiment, the tines may be
approximately wedge-shaped so that an acutely angled edge portion
of each tine can be inserted more deeply into the corresponding
interproximal space between the tooth being filled and an adjacent
tooth. The acutely angled edge portion is generally defined by a
pair of opposing sides that intersect at a predetermined edge
angle. The predetermined edge angle between the sides is preferably
within the range of about 30.degree. to about 90.degree., with a
more preferred range of about 45.degree. to about 75.degree., and a
most preferred angle of about 60.degree..
[0016] According to a preferred embodiment, the flexible member
also comprises means for securely receiving the prongs of a rubber
dam clamp. An example of such means is a pair of apertures
extending through the body member. During use, the prongs of a
rubber dam clamp are inserted into the apertures and a spreading
force is applied with the rubber dam clamp, causing the member to
flex outwardly and the tines to spread apart. Once the tines are
sufficiently spread apart they are placed into the interproximal
spaces between the matrix band and adjacent tooth. The rubber dam
clamp is removed and the spring-back force of the arcuate member
effectively holds the matrix band in an appropriate placement for
providing form for receiving a dental filling.
[0017] One benefit of the invention is that it generally enables
the tines of the matrix band retainer to be spread apart with a
rubber dam clamp in a safe and secure manner. The invention also
generally provides tines that are anatomically configured to be
more easily inserted into the interproximal spaces between teeth
for providing increased contact between a matrix band and the tooth
being filled so as to urge the matrix band into a more anatomically
correct configuration, while reducing the likelihood that the
matrix band retainer will slip out of its holding position.
[0018] These and other features and advantages of the present
invention will become more fully apparent from the following
description and appended claims, or may be learned by practicing
the invention as set forth below.
BRIEF DESCRIPTION OF THE DRAWINGS
[0019] A more extensive description of the present invention,
including the above-recited features and advantages, will be
rendered with reference to the specific embodiments that are
illustrated in the appended drawings. Because these drawings depict
only exemplary embodiments, the drawings should not be construed as
imposing any limitation on the present invention's scope. As such,
the present invention will be described and explained with
additional specificity and detail through use of the accompanying
drawings in which:
[0020] FIG. 1A is a side view of a tooth having a cavity and two
adjacent teeth;
[0021] FIG. 1B is a top view of the tooth of FIG. 1A and two
adjacent teeth;
[0022] FIG. 1C is a top view of the tooth of FIG. 1A with a
hollowed out dental preparation existing in the general area of the
cavity of FIG. 1B and a matrix band placed between the tooth having
the dental preparation and an adjacent tooth;
[0023] FIG. 2 is a top perspective view of one embodiment of the a
matrix band retainer of the invention that includes two tines
having curved and wedge-shaped bodies which are connected by a
flexible member;
[0024] FIG. 3 is a top view of one embodiment of the matrix band
retainer of the invention that includes two apertures that are
configured to receive the prongs of a rubber dam clamp;
[0025] FIG. 4 is a front view of one embodiment of the matrix band
retainer of the invention that comprises two tines that each have a
curved body;
[0026] FIG. 5 is a front view of one embodiment of the matrix band
retainer of the invention that comprises two tines, each having a
curved body and a protruding foot which generally points towards
the foot of the alternate tine;
[0027] FIG. 6 is front view of two teeth and two tines positioned
in the interproximal spaces between the teeth;
[0028] FIG. 7A is a top view of one embodiment of the tine of the
matrix band retainer of the invention that has a cross-sectional
area resembling a right triangle that is inserted within the
interproximal space between two adjacent teeth;
[0029] FIG. 7B is a top view of one embodiment of the tine of the
matrix band retainer of the invention that has a cross-sectional
area resembling an equilateral triangle that is inserted within the
interproximal space between two adjacent teeth;
[0030] FIG. 7C is a top view of one embodiment of the tine of the
matrix band retainer of the invention that has a cross-sectional
area resembling a cone that is inserted within the interproximal
space between two adjacent teeth; and
[0031] FIG. 7D is a top view of one embodiment of the tine of the
matrix band retainer of the invention that has a cross-sectional
area resembling a square that is inserted within the interproximal
space between two adjacent teeth; and
[0032] FIG. 8 is a top perspective view of the matrix band retainer
of the invention positioned about two teeth with the tines of the
matrix band retainer inserted within the interproximal spaces
between the teeth, while holding a matrix band in place against one
of the teeth that has a hollow dental preparation suitable for
receiving a filling material.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0033] The present invention relates to improved matrix band
retainers for use in dental filling procedures. More particularly,
the present invention relates to matrix band retainers having tines
that are anatomically configured to be inserted into the
interproximal spaces between teeth for holding a matrix band in
proper placement against a tooth receiving a dental filling. The
matrix band retainers of the invention are also preferably
configured to receive the prongs of a rubber dam clamp for
spreading the tines in a safe and secure manner.
[0034] In order to clarify and define the terms that are used in
the present application, FIGS. 1A-1C are provided. FIG. 1A shows a
side view of a tooth 10 having a cavity 12 and adjacent teeth 14
and 16. As shown, an interproximal space 30 exists between tooth 10
and each of the adjacent teeth 14 and 16. The term "interproximal
space," as used herein, should be generally construed to include
any space between two adjacent teeth, including spaces existing
proximate the gingiva, lingual surfaces, buccal surfaces, labial
surfaces, and any other space existing between two adjacent
teeth.
[0035] FIG. 1B shows a top view of the teeth of FIG. 1A. As shown,
an interproximal space 30 exists between tooth 10 and each of the
adjacent teeth 14 and 16.
[0036] FIG. 1C illustrates a dental preparation or hollow 32 formed
within tooth 10. Dental preparation 32 is created by removing
portions of tooth 10 with a drill or another suitable device.
Typically, a dental preparation is formed to remove infected and
damaged portions of a tooth, such as cavity 12 of FIG. 1B. Once a
dental preparation is formed, a matrix band is placed against the
tooth for providing form for receiving a filling material within
the dental preparation. FIG. 1C illustrates how a matrix band 34
might be placed between two adjacent teeth in preparation for
receiving a dental filling. In order to place matrix band 34,
conventional dental wedges (not shown) may optionally be used to
further separate teeth 10 and 14 if needed. The matrix band
retainers of the present invention may be used to retain any thin,
flexible matrix band in place in a more anatomically correct
fashion. Anatomical matrix bands that better conform to the shape
of teeth are set forth in co-pending U.S. application Ser. No.,
______ filed Apr. 19, 2001 and entitled "Anatomically Contoured
Matrix Bands for Use in Dental Restoration Procedures". For
purposes of disclosure, the foregoing application is incorporated
herein by reference.
[0037] Although dental filling procedures requiring the use of
matrix band retainers are generally limited to the restoration of
bicuspids and molars, it should be appreciated that the present
invention is not limited to any particular dental procedure nor to
the application of a dental procedure to any particular type of
tooth.
[0038] Turning now to FIG. 2, one presently preferred embodiment of
a matrix band retainer 40 of the invention is illustrated. As
shown, a first tine 50 and a second tine 60 are connected together
by a flexible and resilient arcuate member, designated as member
70. The first and second tines 50 and 60 comprise proximal ends 52
and 62, respectively, which are attached to member 70, and opposing
distal ends 54 and 64, respectively. The first and second tines 50
and 60 also comprise bodies 56 and 66 that extend between proximal
ends 52 and 62 and distal ends 54 and 64, respectively.
[0039] In one embodiment, member 70 and tines 50 and 60 are formed
by shaping a single piece of generally rigid wire. In one presently
preferred embodiment, matrix band retainer 40 comprises stainless
spring steel for providing member 70 with flexibility and
resiliency. It should be appreciated, however, that any appropriate
material can be used to form matrix band retainer 40 and
corresponding components. Suitable materials can include metals,
plastics, and flexible ceramics. In the present embodiment, member
70 also comprises twisted segments 72 and 74 which are formed by
twisting tines 50 and 60 perpendicular to member 70 during
manufacture of the matrix band retainer 40.
[0040] Member 70 also preferably comprises two apertures 76 and 78
which extend completely through member 70. In one preferred
embodiment, apertures 76 and 78 are rounded and are specifically
configured in size and shape to receive the prongs of a rubber dam
clamp. During use, the prongs of a rubber dam clamp are inserted
into apertures 76 and 78 and a spreading force is applied with the
rubber dam clamp that forces member 70 to bend outwardly, causing
tines 50 and 60 to spread apart. Once tines 50 and 60 are
sufficiently spread apart they can be inserted into the
interproximal spaces existing between a tooth and a matrix band for
holding the matrix band in proper placement for receiving a dental
filling, as will be shown and described in reference to FIGS. 6
thru 7D.
[0041] FIG. 3 is a top view of a matrix band retainer according to
the present embodiment. As shown, member 70 has a generally curved
shape and resembles a C-ring. This is merely illustrative, however,
and should not be construed as a limitation. In particular, member
70 can embody virtually any shape so long as it is appropriately
configured for use in dental procedures and provides the desired
spring-back force. For example, in one alternative embodiment,
member 70 comprises a substantially rectilinear shape.
[0042] FIG. 4 is a front view of one embodiment of the matrix band
retainer of the invention in which tines 50 and 60 comprise curved
bodies 56 and 66, respectively. The curvature of tine bodies 56 and
66 is formed by bending tines 50 and 60 during a manufacturing
process. The exact radius of the curvature can be predetermined and
may vary from one embodiment to another for enabling the matrix
band retainer to conform to the size and shape of different teeth.
It should also be appreciated that the radius of curvature of tine
body 56 can vary from the radius of curvature of tine body 66. In
one presently preferred embodiment, however, the radius of
curvature for each of the tine bodies 56 and 66 is the same and is
approximately 1/2 inch. The curvature of tine bodies 56 and 66 is
such that when tines 50 and 60 are inserted in the interproximal
spaces between teeth, proximal and distal ends 52, 62, 54, and 64
make contact with the surfaces against which the tines 50 and 60
are placed. It should be appreciated that curved tines 50 and 60
more closely approximate the tooth anatomy than do straight tines.
Because tines 50 and 60 are curved, they are able to tightly wrap
around the teeth against which they are placed, thereby holding the
matrix band retainer in place and urging the matrix band into a
more anatomically correct configuration against the side of the
tooth being restored.
[0043] The shape and size of the tines can vary to accommodate the
anatomical shape of any tooth. In some instances, the base of the
exposed tooth, near the gingiva, is recessed significantly. In
these instances, for example, the distal end of the tine may
optionally be configured with a protruding foot, as illustrated in
FIG. 5, for providing additional contact with the tooth surface
against which the tine is placed.
[0044] As shown in FIG. 5, distal ends 54 and 64 include feet 54B
and 64B, respectively. Feet 54B and 64B extend away from their
respective distal ends 54 and 64 towards the alternate distal end
54 or 64. The configuration of feet 54B and 64B and the curvature
of the tine bodies 56 and 66 generally approximate the anatomical
shape of the interproximal spaces between teeth, such that when
tines 50 and 60 are inserted into interproximal spaces, feet 54B
and 64B and bodies 56 and 66 make contact with matrix band and
tooth surfaces from within the interproximal spaces between the
teeth. This feature of the invention is useful because it
substantially secures the matrix band retainer in the latitudinal
direction, reducing the likelihood that the matrix band retainer
will slip out of place, and enables the matrix band retainer to
urge the matrix band into an anatomically correct configuration
against the surface of the tooth that is being restored during the
dental filling procedure.
[0045] FIG. 6 further illustrates how the tines of the matrix band
retainer of the invention are anatomically configured to be
inserted into the interproximal spaces between teeth. By way of
comparison, a straight tine 86 and a curved tine 88 are placed in
interproximal spaces 30 between tooth 10 and adjacent tooth 14.
Like most bicuspids and molars, teeth 10 and 14 have profiles that
are generally rounded and trapezoidal.
[0046] Curved tine 88, which is one embodiment of the tine of the
matrix band retainer of the invention, is curved so as to be
anatomically configured to the shape of the interproximal spaces 30
between teeth 10 and 14. As shown, curved tine 88 makes contact
with the surface of tooth 10 over a region that substantially
extends the entire length of curved tine 88. Contact region 92
shows the region of contact that curved tine 88 makes with tooth
10. Curved tine 88 also makes similar contact with adjacent tooth
14. When a matrix band is placed between curved tine 88 and tooth
10 then curved tine 88 urges the matrix band into an anatomically
correct configuration against the surface of tooth 10 for providing
form for receiving a dental filling.
[0047] Straight tine 86, which is another embodiment of the tine of
the matrix band retainer of the invention, has a cross-sectional
area that is anatomically configured to be inserted into the
interproximal spaces 30 between teeth 10 and 14. The
cross-sectional shape of straight tine 86 is generally wedge-shaped
and enables straight tine 86 to be inserted securely into the
interproximal spaces between teeth.
[0048] FIGS. 7A-7D show four embodiments of the tine of the matrix
band retainer of the invention in which each of the tines 100, 110,
120, and 130 is configured with a wedge-shaped body.
[0049] FIG. 7A illustrates a tine 100 comprising a cross-sectional
area that generally resembles a right triangle. An acutely angled
edge 132 of tine 100 exists between contact surfaces 136 and 138
and has an angle is defined by the orientation of contact surfaces
136 and 138. According to this embodiment, acutely angled edge 132
has an angle 134 of about 30.degree.. The term "about", as used in
the specification and appended claims, is generally defined as
.+-.10.degree..
[0050] Contact surface 136 is biased against the surface of tooth
10 while contact surface 138 is biased against the surface of
matrix band 140. It should be appreciated that the wedge-shaped
body of tine 100 enables contact surfaces 136 and 138 to make
better contact with the surfaces of matrix band 140 and tooth 10
then they could make if tine 100 were round. Tine 100 is a
practical embodiment for use in circumstances when the
interproximal spaces between teeth are narrow and deep.
[0051] FIG. 7B illustrates another embodiment of the tine of the
present invention. As shown, tine 11O has a cross-sectional area
approximating an equilateral triangle. An acutely angled edge 142
of tine 110 exists between contact surfaces 146 and 148. In this
embodiment, acutely angled edge 142 has an angle 144 of about
60.degree.. Contact surface 146 is biased against the surface of
tooth 1O while contact surface 148 is biased against the surface of
matrix band 140. Tine 110 is a practical embodiment for use in
circumstances when the interproximal spaces between teeth are
shallow and wide.
[0052] In another embodiment, shown in FIG. 7C, tine 120 has a
cross-sectional area that is substantially triangular and resembles
a cone with rounded backside 150. An acutely angled edge 152 of
tine 120 exists between contact surfaces 156 and 158. In this
embodiment, acutely angled edge 152 has an angle 154 of about
60.degree.. Contact surface 156 is biased against the surface of
tooth 10 while contact surface 158 is biased against the surface of
matrix band 160. This embodiment is preferred in some circumstances
because the rounded backside 150 of tine 120 provides a smooth
surface against which the patient's tongue or cheek can come in
contact without becoming agitated.
[0053] In yet another embodiment, shown in FIG. 7D, tine 130 has a
square cross-sectional area. An acutely angled edge 162 of tine 130
exists between contact surfaces 166 and 168. According to this
embodiment, acutely angled edge 162 has an angle 164 of 90.degree..
Contact surface 166 is biased against the surface of tooth 10 while
contact surface 168 is biased against the surface of matrix band
140. This embodiment may be preferred for manufacturing
reasons.
[0054] It should be appreciated that because the wedge-shaped
design of the tines shown in FIGS. 7A-7D enables the tines to be
inserted deep into the interproximal spaces between the teeth,
thereby securing the matrix band retainer in the latitudinal
direction. The predetermined edge angle formed by the junction of
the contact surfaces of the wedge-shaped tine is preferably within
the range of about 30.degree. to about 90.degree., with a more
preferred range of about 45.degree. to about 75.degree., and a most
preferred angle of about 60.degree..
[0055] The wedge-shaped tine is also useful for providing flat
contact surfaces that frictionally engage the surfaces against
which the tine is placed, thereby keeping the matrix band retainer
in a desired position, without slipping, and urging the matrix band
to conform to the shape of the tooth against which it is placed. In
other embodiments, not shown, the contact surfaces comprise
contours that better approximate the generally round circumference
of a tooth and provide even more frictional contact and holding
capabilities.
[0056] It should be appreciated that although the tines have been
shown in certain embodiments to comprise specific shapes that the
tines of the matrix band retainer of the present invention are not
limited to any predefined shape. Instead, the tines can comprise
any shape that is configured to conform to the anatomical shape of
teeth and to be inserted into the interproximal spaces between
teeth. In some embodiments, this is accomplished by providing tines
that are curved. In other embodiments, this is accomplished by
providing tines that are wedge-shaped. In yet other embodiments,
this is accomplished by providing tines that are both curved and
wedge-shaped.
[0057] Although certain figures of the application illustrate tines
of the matrix band retainer inserted within the interproximal
spaces between teeth comprising bicuspids and molars, it should be
appreciated that the invention is not limited to the practice of
dental procedures to any particular type of tooth. Accordingly, the
tines of the matrix band retainer of the invention can also be
appropriately configured to conform to the anatomical shape of the
interproximal spaces between cuspids, laterals, and centrals.
[0058] Furthermore, it should also be appreciated that references
to tines of the matrix band retainer being inserted into the
interproximal spaces between a matrix band and an adjacent tooth
are only illustrative and not restrictive. In particular, the tines
of the matrix band retainer of the invention can be placed into the
interproximal spaces between two adjacent matrix bands, or between
a tooth and a dental wedge, or between a dental wedge and a matrix
band, or between two dental wedges, or between any combination of
the foregoing and any other device that is used for dental
procedures involving the use of a matrix band retainer.
[0059] For example, as shown in FIG. 8, matrix band retainer 40 can
also be used to hold a matrix band 170 in a desired placement
against a tooth 180 for providing form for filling a hollow dental
preparation 172 with a filling material. According to the present
embodiment, tines 50 and 60 of matrix band retainer 40 are both
curved and wedge-shaped. As shown, tines 50 and 60 are inserted
within the interproximal spaces between teeth 180 and 190. From
this position, tines 50 and 60 apply a direct contact force to
matrix band 170, thereby holding matrix band 170 in a desired
placement.
[0060] The invention, as it has been described herein, generally
enables a matrix band retainer to be conformingly inserted into the
interproximal spaces between teeth. The invention also enables the
tines of the matrix band retainer to be spread apart by using a
rubber dam clamp in a secure and safe manner. It should be
appreciated that these benefits of the invention are advantages
over the prior art.
[0061] It should also be appreciated that the present invention may
be embodied in other forms without departing from its spirit or
essential characteristics. As properly understood, the preceding
description of specific embodiments is illustrative only and in no
way restrictive. The scope of the invention is, therefore,
indicated by the appended claims as follows.
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