NZ604244A - Dental matrix band - Google Patents
Dental matrix bandInfo
- Publication number
- NZ604244A NZ604244A NZ604244A NZ60424412A NZ604244A NZ 604244 A NZ604244 A NZ 604244A NZ 604244 A NZ604244 A NZ 604244A NZ 60424412 A NZ60424412 A NZ 60424412A NZ 604244 A NZ604244 A NZ 604244A
- Authority
- NZ
- New Zealand
- Prior art keywords
- dental matrix
- apertures
- micro
- centre
- metal substrate
- Prior art date
Links
- 239000011159 matrix material Substances 0.000 title claims abstract description 231
- 239000002184 metal Substances 0.000 claims abstract description 135
- 239000000758 substrate Substances 0.000 claims abstract description 133
- 239000011347 resin Substances 0.000 claims abstract description 78
- 229920005989 resin Polymers 0.000 claims abstract description 78
- 229920000642 polymer Polymers 0.000 claims abstract description 60
- 239000000463 material Substances 0.000 claims abstract description 19
- 239000011248 coating agent Substances 0.000 claims description 29
- 238000000576 coating method Methods 0.000 claims description 29
- NBVXSUQYWXRMNV-UHFFFAOYSA-N Fluoromethane Chemical group FC NBVXSUQYWXRMNV-UHFFFAOYSA-N 0.000 claims description 17
- 239000002131 composite material Substances 0.000 claims description 13
- 238000001259 photo etching Methods 0.000 claims description 10
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 10
- -1 polytetra- fluoroethylene Polymers 0.000 claims description 9
- 229940058401 Polytetrafluoroethylene Drugs 0.000 claims description 8
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 8
- 238000003892 spreading Methods 0.000 claims description 7
- 239000011888 foil Substances 0.000 claims description 6
- 229910001220 stainless steel Inorganic materials 0.000 claims description 5
- 239000010935 stainless steel Substances 0.000 claims description 5
- 229920002068 Fluorinated ethylene propylene Polymers 0.000 claims description 3
- 239000004812 Fluorinated ethylene propylene Substances 0.000 claims description 3
- 229920001774 Perfluoroether Polymers 0.000 claims description 3
- 210000003660 Reticulum Anatomy 0.000 claims description 3
- HQQADJVZYDDRJT-UHFFFAOYSA-N ethene;prop-1-ene Chemical group C=C.CC=C HQQADJVZYDDRJT-UHFFFAOYSA-N 0.000 claims description 3
- 238000010438 heat treatment Methods 0.000 claims description 3
- 229920000728 polyester Polymers 0.000 claims description 3
- 238000005507 spraying Methods 0.000 claims description 3
- 210000000515 Tooth Anatomy 0.000 description 33
- 238000004519 manufacturing process Methods 0.000 description 8
- 238000000034 method Methods 0.000 description 8
- 238000005530 etching Methods 0.000 description 7
- 229920002120 photoresistant polymer Polymers 0.000 description 7
- 238000004140 cleaning Methods 0.000 description 5
- 238000005520 cutting process Methods 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 238000003384 imaging method Methods 0.000 description 3
- 241000264877 Hippospongia communis Species 0.000 description 2
- 239000002253 acid Substances 0.000 description 2
- 239000000805 composite resin Substances 0.000 description 2
- 238000001035 drying Methods 0.000 description 2
- 230000002708 enhancing Effects 0.000 description 2
- 239000004033 plastic Substances 0.000 description 2
- 229920003023 plastic Polymers 0.000 description 2
- RBTARNINKXHZNM-UHFFFAOYSA-K Iron(III) chloride Chemical compound Cl[Fe](Cl)Cl RBTARNINKXHZNM-UHFFFAOYSA-K 0.000 description 1
- 239000004698 Polyethylene (PE) Substances 0.000 description 1
- 229920002803 Thermoplastic polyurethane Polymers 0.000 description 1
- 239000007864 aqueous solution Substances 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000003518 caustics Substances 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 230000000295 complement Effects 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 239000007822 coupling agent Substances 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 239000012528 membrane Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006011 modification reaction Methods 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229920001296 polysiloxane Polymers 0.000 description 1
- 230000000717 retained Effects 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229920001221 xylan Polymers 0.000 description 1
- 150000004823 xylans Chemical class 0.000 description 1
Abstract
Patent 604244 Disclosed herein is a dental matrix for use in repairing and restoring cavities with light-cured restorative material, the dental matrix comprising: a metal substrate comprising a plurality of micro-apertures, wherein the microapertures are filled with a transparent or semi transparent resin, and a polymer layer covering the metal substrate and the resin filled micro-apertures for contacting the tooth in use. sparent resin, and a polymer layer covering the metal substrate and the resin filled micro-apertures for contacting the tooth in use.
Description
NEW ZEALAND
PATENTS ACT, 1953
No: 599181; 599477; 603021
Date: 2 April 2012; 19 April 2012; 12 October 2012
COMPLETE SPECIFICATION
DENTAL MATRIX BAND
I, SIMON PAUL McDONALD, a New Zealand citizen of 4B Sheffield Street, Katikati 3129
New Zealand, do hereby declare the invention for which I pray that a patent may be
granted to me, and the method by which it is to be performed, to be particularly
described in and by the following statement:
FIELD OF THE INVENTION
This invention relates to a new dental matrix device for assisting dentists to form and
successfully light cure composite dental restorations on tooth surfaces, and a method for
manufacturing a new dental matrix device.
SUMMARY OF THE PRIOR ART
Matrices and the use of matrix systems are well known and widely utilized in
restorative dentistry. There are many types of matrices available and are generally
made entirely of metal or plastic and are sectional or circumferential bands. Plastic
matrices generally are thicker than metal matrices and this causes problems obtaining
tight inter-proximal contacts. For this reason, metal matrices have been more popular
for posterior teeth.
During the restoration of an inter-proximal cavity, the matrix band is secured around
the tooth and cavity and forms a mould. This mould is filled with composite material
and the composite is light cured. The difficulty with curing an inter-proximal
restoration is that once the metal matrix band is wrapped around the tooth, the matrix
band does not allow horizontal curing of the composite at the gingivo-proximal tooth
surface. It has to be cured from above and this can lead to incomplete curing of the
composite resin. When this occurs, composite resin can adhere to the metal matrix
rather than the tooth and detach from the restoration when the matrix is removed.
The restoration must then be re-done or repaired.
Prior art exists of metal matrices with one or two open areas covered with a
membrane of transparent material and of matrices with illuminating ports with port
covers. These open areas and ports cover a relatively large area of the matrix and
because these openings are either covered by a port cover or covered by a very thin
expanding film, in-use, they may result in restorations with poor anatomical form.
It is an object of the present invention to provide the dentist with a means of firmly
retaining the composite material with a metallic matrix while enabling light curing of
the composite, or to at least provide dental practitioners with a useful choice.
SUMMARY OF THE INVENTION
In a first aspect the invention consists in a dental matrix for use in repairing and restoring
cavities with light-cured restorative material, the dental matrix comprising:
a metal substrate comprising a plurality of micro-apertures, wherein the micro-
apertures are filled with a transparent or semi transparent resin, and
a polymer layer covering the metal substrate and the resin filled micro-apertures
for contacting the tooth in use.
In some embodiments the transparent or semi-transparent resin used to fill the micro-
apertures is also used to form the polymer layer covering the metal substrate.
In some embodiments the polymer layer is formed of a polymer that does not stick to the
dental restorative material, the polymer layer forming a smooth non-stick surface finish.
In some embodiments the polymer layer is a fluorocarbon. In some embodiments the
fluorocarbon is polytetra-fluoroethylene. In some embodiments the fluorocarbon is
fluorinated ethylene propylene. In some embodiments the fluorocarbon is
perfluoroalkoxy.
In some embodiments the polymer layer has a thickness of 25micron or less.
In some embodiments the dental matrix comprises a layer of the resin on a side of the
dental matrix opposite the polymer layer. In some embodiments the dental matrix has no
layer of resin on a side of the dental matrix opposite the polymer layer.
In some embodiments the metal substrate is a foil.
In some embodiments the metal substrate is a stainless steel substrate.
In some embodiments the metal substrate has a thickness of 20 – 50 micron.
In some embodiments each of the plurality of micro-apertures has an area of between
300 and 80,000 square microns.
In some embodiments the plurality of micro-apertures comprises circular micro-apertures.
In some embodiments the plurality of micro-apertures comprises hexagonal micro-
apertures. In some embodiments the plurality of micro-apertures comprises oval micro-
apertures. In some embodiments the plurality of micro-apertures comprises elongate
micro-apertures or slots each having a length greater than a width. In some
embodiments a width of each of the elongate micro-apertures or slots is 50 to 180
micron. In some embodiments each elongate aperture has a length and a width and a
ratio of the length and the width is 1.2 to 5. In some embodiments the ratio of the width
of each of the plurality of micro-apertures and the thickness of the metal substrate is
greater than 2. In some embodiments the ratio of the width of each of the plurality of
micro-apertures and the thickness of the metal substrate is greater than 3. In some
embodiments each of the plurality of micro-apertures is circular and 20 to 180 micron in
diameter. In some embodiments the ratio of the diameter of each of the plurality of
micro-apertures and the thickness of the metal substrate is greater than 2. In some
embodiments the ratio of the diameter of each of the plurality of micro-apertures and the
thickness of the metal substrate is greater than 3.
In some embodiments the micro-apertures are arranged in a concentric archway pattern.
In some embodiments the micro-apertures are arranged in a honeycomb pattern.
In some embodiments the plurality of micro-apertures comprises elongate micro-
apertures each having a length greater than a width, and at least some of the elongate
micro apertures being arranged in concentric rings about a centre or centre region each
with its length aligned approximately towards the centre or centre region. In some the
centre or centre region may be located on the dental matrix to be positioned between the
lingual side of the tooth and the buccal side of the tooth in use. In some the centre or
centre region is positioned on the dental matrix, in use the elongate micro-apertures
located above the centre each with its length aligned approximately towards the centre or
centre region and the elongate micro-apertures located below the centre each with its
length aligned approximately horizontally. In some embodiments the elongate micro
apertures located below the centre are arranged in columns. In some embodiments the
centre is located adjacent a bottom edge of the dental matrix. In some embodiments the
plurality of micro-apertures comprises two groups of micro-apertures, each group of
micro-apertures comprising elongate micro-apertures each having a length greater than a
width, and at least some of the elongate micro apertures being arranged in concentric
rings about a centre or centre region each with its length aligned approximately towards
the centre or centre region. In some embodiments the two groups of micro-apertures are
located either side of a centre line of the dental matrix.
In some embodiments the thickness of the dental matrix is less than 60 micron. In some
embodiments the thickness of the dental matrix is less than 50 micron. In some
embodiments the thickness of the dental matrix is less than 45 micron.
In some embodiments the dental matrix is a sectional matrix. In some embodiments the
dental matrix is a shaped circumferential band. In some embodiments the dental matrix is
a straight edged circumferential band.
In a second aspect the invention consists in a dental matrix for use in repairing and
restoring cavities with light-cured restorative material, the dental matrix comprising:
a metal substrate comprising a plurality of micro-apertures, wherein the plurality
of micro-apertures comprises elongate micro-apertures each having a length greater than
a width, and at least some of the elongate micro apertures being arranged in concentric
rings about a centre or centre region each with its length aligned approximately towards
the centre or centre region.
In some embodiments the centre or centre region may be located on the dental matrix to
be positioned between the lingual side of the tooth and the buccal side of the tooth in use.
In some embodiments the centre or centre region is positioned on the dental matrix, in
use the elongate micro-apertures located above the centre each with its length aligned
approximately towards the centre or centre region and the elongate micro-apertures
located below the centre each with its length aligned approximately horizontally.
In some embodiments the elongate micro apertures located below the centre are arranged
in columns.
In some embodiments the centre is located adjacent a bottom edge of the dental matrix.
In some embodiments the plurality of micro-apertures comprises two groups of micro-
apertures, each group of micro-apertures comprising elongate micro-apertures each
having a length greater than a width, and at least some of the elongate micro apertures
being arranged in concentric rings about a centre or centre region each with its length
aligned approximately towards the centre or centre region.
In some embodiments the two groups of micro-apertures are located either side of a
centre line of the dental matrix.
In some embodiments the micro-apertures are arranged in a concentric archway pattern.
In a third aspect the invention consists in a method of forming a dental matrix for use in
repairing and restoring cavities in a tooth with light-cured composites, the method
comprising:
i) providing a metal substrate,
ii) coating a side of the metal substrate with a polymer to form a polymer layer on
a side of the dental matrix for contacting the tooth in use,
iii) forming micro-apertures in the metal substrate by photo etching a reverse side
of the metal substrate without breaking the polymer layer.
In some embodiments the method comprises:
iv) filling the micro-apertures with a transparent or semi-transparent resin.
In some embodiments the method comprises applying the resin to the metal substrate by
an apparatus that simultaneously fills the micro apertures and removes substantially all
resin from the reverse side of the dental matrix. In some embodiments the method
comprises applying the resin to the metal substrate by an apparatus that simultaneously
fills the micro apertures and leaves a layer of resin on the reverse side of the dental
matrix. In some embodiments the apparatus comprises one or more of a roller and a
squeegee or blade like apparatus.
In some embodiments the method comprises providing a parent metal substrate and
subsequently separating the dental matrix from the parent metal substrate.
In some embodiments the method comprises photo etching at least a portion of a
perimeter of the dental matrix for separating the dental matrix from the parent metal
substrate, and separating the dental matrix from the parent metal substrate by breaking
the polymer coating at the perimeter of the dental matrix.
In some embodiments the method comprises adding a photo-resistive film to the reverse
side of the metal substrate after the coating is added to the metal substrate.
In some embodiments the method comprises providing the parent metal substrate as a
metal strip.
In some embodiments the metal strip is provided in a coil, and the method comprises
unwinding the metal strip from the coil for the polymer layer to be applied.
In some embodiments the method comprises spraying the polymer onto a surface of the
metal substrate, and heating the metal substrate with sprayed polymer in an oven to form
the polymer layer on the metal strip.
In some embodiments the method comprises applying the resin to the metal substrate
using a squeegee or blade like apparatus for spreading the resin into the apertures.
In some embodiments the method comprises applying the resin to the metal substrate
using a squeegee or blade like apparatus for spreading the resin into the apertures and to
leave a layer of resin on the reverse side of the dental matrix. In some embodiments the
method comprises applying the resin to the metal substrate using a squeegee or blade
like apparatus for spreading the resin into the apertures and to substantially remove all
resin from the reverse side of the dental matrix.
In some embodiments the polymer is a fluorocarbon to form a fluorocarbon layer. In
some embodiments the polymer is polytetra-fluoroethylene to form a polytetra-
fluoroethylene layer.
In some embodiments the polymer layer has a thickness of 25micron or less.
In some embodiments the method comprises the resin is one of a fluorocarbon, polytetra-
fluoroethylene, a polyester.
In some embodiments the method comprises the metal substrate is a foil.
In some embodiments the method comprises the metal substrate is a stainless steel
substrate.
In some embodiments the method comprises the metal substrate has a thickness of 20 –
50 micron.
The term “comprising” as used in this specification and claims means “consisting at least
in part of”. When interpreting each statement in this specification and claims that
includes the term “comprising”, features other than that or those prefaced by the term
may also be present. Related terms such as “comprise” and “comprises” are to be
interpreted in the same manner.
It is intended that reference to a range of numbers disclosed herein (for example, 1 to 10)
also incorporates reference to all rational numbers within that range (for example, 1, 1.1,
2, 3, 3.9, 4, 5, 6, 6.5, 7, 8, 9 and 10) and also any range of rational numbers within that
range (for example, 2 to 8, 1.5 to 5.5 and 3.1 to 4.7) and, therefore, all sub-ranges of all
ranges expressly disclosed herein are hereby expressly disclosed. These are only
examples of what is specifically intended and all possible combinations of numerical
values between the lowest value and the highest value enumerated are to be considered
to be expressly stated in this application in a similar manner.
The invention consists in the foregoing and also envisages constructions of which the
following gives examples only.
BRIEF DESCRIPTION OF THE DRAWINGS
A preferred embodiment of the present invention will now be described with reference to
the accompanying drawings in which;
Figure 1 illustrates a dental matrix according to one embodiment of the present invention.
Figure 2 illustrates a dental matrix according to another embodiment of the present
invention.
Figure 3 illustrates a schematic part cross section of a dental matrix according to one
embodiment of the present invention.
Figure 4 illustrates a schematic part cross section of a dental matrix according to another
embodiment of the present invention.
Figure 5 illustrates a shaped circumferential band dental matrix according to another
embodiment of the present invention.
DETAILED DESCRIPTION OF THE PRESENT INVENTION
A dental matrix band comprising features of the present invention is described with
reference to Figures 1 to 3. Figure 1 shows a first embodiment of the present
invention consisting of a sectional matrix, and Figure 2 shows an alternative
embodiment. Figure 3 shows a cross section through a dental matrix comprising
features of the present invention. Whenever possible, common reference numbers will
be utilized to refer to common elements and features in each of the embodiments
described.
Each dental matrix 10 illustrated in Figures 1 and 2 comprises a matrix body 12
having a tab 14 with a first bore 16 disposed on the top border of the matrix body 12
and a second and third bore 18, 20 disposed adjacent to either side edge of the matrix
body 12. Tab 14 provides the dentist with a section of material where the matrix can
be grabbed with a dental instrument and moved into or out of position in the patient's
mouth. The first, second and third bores 16, 18, 20 further assist in the dentist in
placing, positioning, and extracting the matrix 10 and are particularly useful when the
dentist is using a pinned tweezers or other dental instrument having a pin or hook for
attaching to various items. The matrix body 12 terminates at its lower margin at a
flange portion 22 at the lower portion of the matrix body 12. The flange portion 22
addresses the tooth being restored at the gingival margin. While the dental matrices
10 shown each includes a gingival flange portion 22, tab 14 and holes 16, 18 and 20,
it is contemplated that the dental matrix can be manufactured with only a dental
matrix body 12 and without a gingival flange portion or tab 12 or holes 16, 18 and 20
without falling outside the scope of the invention. When the dental matrix 10 is
without a gingival flange portion, the bottom edge of the dental matrix body 12 forms
the bottom edge of the dental matrix 10.
In one embodiment, the matrix body 12 exhibits a degree of curvature along both its
longitudinal axis (horizontal axis in use) and latitudinal axis (vertical axis in use), thus
enabling the matrix body 12 to be formed into a shape complementary with and
against a tooth be restored.
The matrix body 12 is formed from a metal substrate or foil 13, for example a
stainless steel foil. Preferably the metal substrate has a thickness of 20 to 50 micron
(micrometre, µm).
As shown in Figures 1 and 2, the matrix body 12 further comprises a plurality of light-
transmitting micro-apertures 24, 26. Preferably the micro-apertures generally cover a
majority of the matrix body 12 and flange portion 22, and at least an area of the
matrix body that in use overlays the inter-proximal surface of a tooth to be restored.
The micro-apertures 24, 26 are positioned on the matrix body 12 and gingival flange
portion 22 such that when the matrix 10 is formed into the desired configuration
around the tooth being restored, the micro-apertures 24, 26 align with the inter-
proximal tooth surface of the tooth being restored.
In the embodiment shown in Figure 2, each micro-aperture is substantially circular
and is approximately 20 to 180 micron in diameter. In one embodiment a ratio of the
diameter of the micro-apertures and the thickness of the metal substrate of the matrix
is greater than 2. In another embodiment a ratio of the diameter of the micro-
apertures and the thickness of the metal substrate of the matrix is greater than 3.
When light is shined through the matrix, the thickness of the matrix and the aperture
size determines the amount of light that can pass through the matrix for a given angle
of incidence of light to the plane of the matrix. For example, for a ratio of greater
than 2, the angle of incidence for light to pass through the matrix must be greater
than about 27degrees. For a ratio of greater than 3, the angle of incidence for light to
pass through the matrix must be greater than about 19degrees.
The micro-apertures can be different shapes and configurations, including elongated
apertures such as slots as shown in the embodiment of Figure 1, hexagonal shaped
apertures or oval apertures (not illustrated) for example.
Referring to the embodiment of Figure 1, the micro-apertures 24 consist of elongated
apertures or slots having a length of approximately 50 to 180 micron. Preferably the
length is 1.2 to 5 times the width of the slots. In one embodiment a ratio of the width
of the micro-apertures and the thickness of the metal substrate of the matrix is
greater than 2. In another embodiment a ratio of the width of the micro-apertures
and the thickness of the metal substrate of the matrix is greater than 3.
The micro-apertures 24, 26 can be arranged in a number of different configurations.
In Figure 2, the substantially circular micro-apertures are arranged in a staggered or
honey comb configuration 5. In an alternative embodiment the micro-apertures may
be aligned in columns.
In the embodiment of Figure 1, at least some of the slots 24 are arranged in
concentric rings 4 about a centre or centre region 25, each slot with its length aligned
approximately towards the centre. The arrangement of apertures 24 in the
embodiment of Figure 1 may be described as a concentric archway pattern. As
illustrated, the centre may be located centrally between side edges of the dental
matrix, or located between the lingual side of the tooth and the buccal side of the
tooth to be treated in use.
As shown in Figure 1, the centre 25 may be positioned on the dental matrix (within
the perimeter of the dental matrix). In the illustrated embodiment, the slots located
above the centre 25 are each arranged with its length aligned approximately towards
the centre 25. The slots located below the centre each have its length aligned
approximately horizontally. As shown, the slots arranged horizontally are formed in
columns, however these slots may be arranged in a staggered arrangement, like the
circular apertures in the embodiment of Figure 2. Further, the apertures below the
centre, for example on the area of the flange portion 22, may be other shapes, for
example circular. In a further alternative embodiment that does not comprise a flange
portion 22, the centre 25 of the aperture pattern may be located at or near to a
bottom edge of the matrix. In a further alternative embodiment, non-elongated micro
apertures may be arranged in a concentric archway pattern. For example, circular
apertures may be formed in a concentric archway pattern with the circular apertures
arranged in concentric rings about a centre or centre region.
The alignment of the slots or elongate apertures (for example oval or other elongated
shape) in the embodiment illustrated in Figure 1 facilitates light entry of light beams from
a curing light source into the micro-apertures at an angle from above normal to the plane
of the matrix. The micro-apertures also allow light to enter from substantially horizontal
to the plane of the matrix. Arranging elongated micro-apertures in the circular manner
with respect to a centre 25 reduces or eliminates the need to align the light source
directly perpendicular or normal to the matrix, which becomes increasingly difficult as the
micro-apertures fall further into the inter-proximal space, while still enabling maximum
light transmission through the dental matrix.
It is desired that that the interior surface of the matrix 10 be smooth and free from
blemishes or imperfections that may transferred to the composite material and formed
into the restoration. To maintain the smooth interior surface of the matrix 10 that
contacts the tooth in use, the individual micro-apertures are filled with a transparent,
light transmitting material 28, as illustrated in the cross sectional view of Figure 3.
Preferably, the micro-apertures are filled with a resin or polymer, for example one of a
fluorocarbon or a polyester. It is contemplated that any suitable transparent or semi-
transparent, light transmitting material may be used to fill the micro-apertures. A
suitable resin may have a compressive strength of about 7,000psi (ASTM D695). A
suitable resin may have a flexural modulus of about 50,000 – 65,000psi (ASTM D790). A
suitable resin may have a tensile strength of about 3,000psi to 6,000psi (ASTM D638). A
suitable resin may have an elongation of about 25% (ASTM D2370). The resin may
comprise a urethane resin. The resin may comprise compounds to enhance release
properties. For example the resin may comprise one or more of co-polymerisable silicone
and polyethylene wax. The resin may comprise components to enhance adhesion to the
substrate. For example the resin may comprise an acid coupling agent.
In one embodiment illustrated in Figure 4, the apertures 24 are filled with resin and a
resin layer 29 is also formed or provided to the exterior surface of the matrix that does
not contact the tooth to be treated in use. In the embodiment illustrated in Figure 3,
there is no resin layer or a very thin resin layer on the exterior surface of the matrix. This
form of the matrix provides a thinner matrix which is preferred.
Preferably the thickness of the matrix illustrated in either Figure 3 or 4 is less than 60
micron. More preferably the thickness is less than 50 micron, and most preferably the
thickness is less than 45 micron, for example a thickness of around 40 micron.
Also, as illustrated in Figure 3, a transparent, light transmitting film 30 is provided to the
surface of the dental matrix 10 that contacts the tooth in use. The film or layer 30 covers
the metal substrate 13 and the resin filled micro apertures and presents a smooth surface
31 for contact with the tooth. Preferably, the film 30 is a polymer layer, for example a
fluorocarbon layer such as polytetra-fluorocarbon, for example Dupont's Teflon®,
Whitford Corporation's Xylan® or other suitable alternative material such as fluorinated
ethylene propylene, or perfluoroalkoxy. Preferably the polymer layer is formed of a
polymer that does not stick to the dental restorative material so that the polymer forms a
non-stick smooth surface finish. In one embodiment, the polymer layer 30 is formed from
the resin used to fill the micro-apertures. Preferably the thickness of the polymer layer is
micron or less.
An alternative matrix is illustrated in Figure 5. The matrix of Figure 5 is a shaped
circumferential band. The matrix of Figure 5 comprises a grouping of micro-apertures
positioned to one side of a centre line 42 of the matrix. In the illustrated embodiment,
the matrix comprises two groupings of micro-apertures 24A and 24B. Each grouping of
micro apertures comprises a concentric archway pattern as described with reference to
the embodiment of Figure 1. Each grouping 24A and 24B comprises slots arranged in
concentric rings 4 about a centre or centre region 25, each slot with its length aligned
approximately towards the centre. In use, the centre 25 of each grouping of apertures
may be located between the lingual side of the tooth and the buccal side of the tooth to
be treated, or on the lingual side of the tooth or the buccal side of the tooth to be treated.
Other variations described with reference to the embodiment of Figure 1 may be
incorporated into a circumferential matrix band as described with reference to the
embodiment of Figure 5.
The new dental matrix 10 operates in the following manner. First, the dentist prepares
an inter-proximal cavity on the surface of the tooth being restored to receive the light-
cured composite/restoration material. The dental matrix 10 is then inserted into the
interproximal space and held securely against the tooth being restored with a retaining
device. Next, to ensure there is no leaking of the composite between the dental matrix
and tooth, a dental wedge may be inserted into the inter-proximal space to hold
the dental matrix 10 firmly against the surface of the tooth being restored. The wedge
may be inserted before or after a retaining device is applied to hold the matrix in
place. Once the dental matrix 10 is secured in position, the cavity is then filled with
composite material. Finally, the composite is light-cured from an occlusal direction as
per normal but can also be cured horizontally through the micro-apertures in the
dental matrix.
Method of manufacture
A method for manufacturing a dental matrix band comprising features of the present
invention is described below.
A metal substrate is coated on one side with a film or layer 30. Preferably the metal
substrate has a thickness of 20 to 50 micron. To apply the layer 30 on the substrate, the
coating material 30 may be sprayed on to a surface of the metal substrate. For example,
a fluorocarbon such as polytetra-fluorocarbon, for example Dupont's Teflon® is sprayed
onto a surface of the metal substrate. The applied coating and metal substrate is
preferably baked in an oven to dry or set the coating material on the substrate to form
the film or layer 30. For example the substrate and applied coating material is baked in
an oven at a temperature of about 360 C to about 400 C. In some embodiments, the
substrate with coating is baked or cured in an oven for about 30 seconds or less than 30
seconds. In some embodiments, the metal substrate is preheated before the coating
material is applied. For example, the metal substrate is preheated in an oven at a
temperature of about 400 C to about 420 C. In some embodiment, the metal substrate is
preheated for period of about 10 seconds, or less than 10 seconds. In some
embodiments, the substrate with coating is subjected to a pre-drying process by heating
with infrared radiation prior to baking in an oven. In some embodiments, the coating is
o o o
heated by infrared radiation at about 100 C, or about 90 C to 100 C. In some
embodiments, the substrate with coating is preheated by infrared radiation for a period of
about 20 seconds, or less than 20 seconds. Preferably the coating has a thickness of less
than about 25 microns.
After the coating has been applied to the metal substrate, micro-apertures 24, 26 are
formed in the metal substrate by photo etching the metal substrate from a reverse or
opposite side of the metal substrate.
A reverse or opposite side to the coated side of the metal substrate comprises a photo-
resisting film. The photo resistive film or layer may be applied before or after the coating
30 is applied to the metal substrate. For example, a side of the metal substrate is
cleaned with a cleaning solution, for example a caustic degreaser. The cleaned surface is
then coated with a UV light sensitive photo resist. A stencil and/or imaging system may
be used to expose a desired configuration for the micro-apertures on the photo resistive
film. Other features of the matrix may also be exposed on the photo resist. Exposure, for
example using UV light, prepares areas of the resisting film to form a resistant film on the
surface of the substrate. The substrate is then washed, for example with a developing
solution, to wash away unexposed photo-resisting film to expose the metal substrate
according to a pattern produced by the stencil or imaging system. Areas of the exposed
photo resist remain on the surface of the metal substrate. The photo-resist film and
developing solution may be any suitable commercially available films and solutions
suitable for use in the photo etching process. The metal substrate with developed film is
then etched to dissolve the metal exposed through the photo restive film. For example
the metal substrate with developed resistive film and coating 30 is placed in a etching
bath and the exposed metal of the substrate is removed by chemical etching. The etchant
may be an aqueous solution of acid, for example ferric chloride. In one embodiment the
etchant is heated and directed under pressure at the substrate coated with developed
photo resist film. The etchant reacts with the unprotected surfaces of the metal substrate
to corrode the metal quickly. After etching, the metal substrate with coating 30 is washed
and rinsed to neutralize and/or remove the etchant. The etched metal substrate may be
cleaned and dried. Photo resist film remaining on the surface of the metal substrate may
be removed, for example by chemically removing the photo resist layer with a suitable
resist stripper, and the metal substrate comprising micro-apertures may be cleaned and
dried.
In some embodiments the polymer coating is not affected by the chemicals used in the
etching process. Therefore the photo etching process for forming the micro-apertures
does not damage the coating on the surface of the metal substrate 30. Therefore the
manufacturing process described produces a matrix band comprising metal substrate with
micro-apertures, and a polymer layer covering a side of the metal substrate and the micro
apertures in the metal substrate. The micro-apertures are etched away leaving only a
layer of polymer over each micro-aperture.
Preferably a parent metal substrate is prepared with a plurality of matrix bands for
subsequent division from the parent metal substrate into individual matrix bands
comprising the metal substrate with micro apertures and polymer coating. For example,
in some embodiments, a continuous strip of metal substrate is coated with polymer. In
some embodiments, a continuous strip metal substrate is passed through a continuous
coating line. In some embodiments a continuous coating line comprises one or more of
preheating the metal strip, spray coating the strip with a polymer coating, infrared pre-
drying and oven curing. The polymer coated strip is then passed through the photo
etching process to prepare many dental matrices along the strip. Following the etching
process the strip may be passed through a press-tool and/or cutting dies to stamp each
matrix from the strip. For example, a press tool is may be configured to accept a
continuous strip being fed into the tool by a tractor-feed mechanism. In some
embodiments, in a stamping process 3-dimensional forms can be pressed into the metal
substrate.
In some embodiments, an outline or perimeter of the matrix band is etched in the photo
etching process. The perimeter of the matrix may be incorporated into the stencil and/or
imaging system to be etching together with the etching of the micro-apertures. For
example, substantially the full perimeter of the matrix band can be etched, or the full
perimeter of the matrix band may be etched. Where the full perimeter of the matrix band
is etched, each individual matrix band may be retained in position in the parent metal
substrate by the polymer coating. Each individual matrix may be separated from the
parent substrate by breaking or cutting the polymer coating at the perimeter of the
matrix. For example, the matrix may be pressed out with a forming tool for forming the
matrix into a 3-dimensional configuration. In some embodiments, the matrix is shaped
by a first conventional press tool, and pushed out of the parent material by a second
forming tool. The perimeter of the matrix may be shaped to include tabs 14. Other
features, for example holes 16, 18 and 20 may be etched in the photo etching process.
By etching away the outline periphery of the matrix, the matrix is separated from the
parent metal substrate without the requirement for cutting dies or the like. Press tooling
and cutting dies require frequent repair and maintenance. Their elimination can result in
an improvement in manufacturing efficiency, and/or savings in manufacturing costs.
The manufacturing method enables the production of micro apertures in the matrix that
are covered on one side by a polymer layer. The micro-apertures allow light to pass
through making the metal matrix 'transparent'.
In some embodiments the method comprises filling the micro apertures with resin 28. In
some embodiments the resin is applied to the metal substrate by an apparatus that
simultaneously fills the micro apertures and removes substantially all resin from the
reverse side of the dental matrix. In some embodiments the resin is applied to the metal
substrate by an apparatus that simultaneously fills the micro apertures and leaves a thin
layer 30 of resin on the reverse side of the dental matrix. In some embodiments the
resin may be spread over the surface and forced into the micro apertures by a roller or
rollers. The metal substrate comprising micro-apertures and polymer coating and with
resin applied to the reverse side of the metal substrate may be passed through rollers for
forcing the resin into the micro apertures. In some embodiments the resin may be
provided to a roller and the roller being in contact with the reverse side of the matrix
presses the resin into the apertures. In some embodiments the roller may leave a thin
layer 30 of resin on the reverse side of the dental matrix. In some embodiments, the
roller may remove substantially all resin from the reverse side of the dental matrix to
achieve the cross section illustrated in Figure 3. In some embodiments the resin may be
applied to the metal substrate using a squeegee or blade like apparatus for spreading the
resin into the apertures. In some embodiments, the squeegee may leave a thin layer 30
of resin on the reverse side of the dental matrix. In some embodiments, the squeegee
may remove substantially all resin from the reverse side of the dental matrix to achieve
the cross section illustrated in Figure 3. In some embodiments a squeegee or blade like
instrument is used to remove recess resin from the reverse side of the dental matrix after
the resin has been provided to the micro-apertures, for example by a roller or rollers.
Preferably the micro-apertures are filled with resin prior to separating the dental matrix
from the parent metal substrate. In the embodiment illustrated in Figure 4, the layer of
resin 4 is broken or cut at the perimeter of the dental matrix to separate the dental matrix
from the parent substrate.
The foregoing description of the invention includes preferred forms thereof. Modifications
may be made thereto without departing from the scope of the invention as defined by the
accompanying claims.
Claims (71)
1. A dental matrix for use in repairing and restoring cavities with light-cured restorative material, the dental matrix comprising: 5 a metal substrate comprising a plurality of micro-apertures, wherein the micro- apertures are filled with a transparent or semi transparent resin, and a polymer layer covering the metal substrate and the resin filled micro-apertures for contacting the tooth in use. 10
2. A dental matrix as claimed in claim 1 wherein the transparent or semi-transparent resin used to fill the micro-apertures is also used to form the polymer layer covering the metal substrate.
3. A dental matrix as claimed in claim 1 wherein the polymer layer is formed of a 15 polymer that does not stick to the dental restorative material, the polymer layer forming a smooth non-stick surface finish.
4. A dental matrix as claimed in claim 3 wherein the polymer layer is a fluorocarbon. 20
5. A dental matrix as claimed in claim 4 wherein the fluorocarbon is a polytetra- fluoroethylene.
6. A dental matrix as claimed in claim 4 wherein the fluorocarbon is fluorinated ethylene propylene.
7. A dental matrix as claimed in claim 4 wherein the fluorocarbon is perfluoroalkoxy.
8. A dental matrix as claimed in any one of the preceding claims wherein the polymer layer has a thickness of 25micron or less.
9. A dental matrix as claimed in any one of the preceding claims wherein the dental matrix comprises a layer of the resin on a side of the dental matrix opposite the polymer layer. 35
10. A dental matrix as claimed in any one of claims 1 to 8 wherein the dental matrix has no layer of resin on a side of the dental matrix opposite the polymer layer.
11. A dental matrix as claimed in any one of the preceding claims wherein the metal substrate is a foil.
12. A dental matrix as claimed in any one of the preceding claims wherein the metal 5 substrate is a stainless steel substrate.
13. A dental matrix as claimed in any one of the preceding claims wherein the metal substrate has a thickness of 20 – 50 micron. 10
14. A dental matrix as claimed in any one of the preceding claims wherein each of the plurality of micro-apertures has an area of between 300 and 80,000 square microns.
15. A dental matrix as claimed in any one of the preceding claims wherein the plurality of micro-apertures comprises circular micro-apertures.
16. A dental matrix as claimed in any one of the preceding claims wherein the plurality of micro-apertures comprises hexagonal micro-apertures.
17. A dental matrix as claimed in any one of the preceding claims wherein the plurality 20 of micro-apertures comprises oval micro-apertures.
18. A dental matrix as claimed in any one of the preceding claims wherein the plurality of micro-apertures comprises elongate micro-apertures or slots each having a length greater than a width.
19. A dental matrix as claimed in claim 18 wherein a width of each of the elongate micro-apertures or slots is 50 to 180 micron.
20. A dental matrix as claimed in claim 18 or 19 wherein each elongate aperture has a 30 length and a width and a ratio of the length and the width is 1.2 to 5.
21. A dental matrix as claimed in any one of claims 18 to 20 wherein the ratio of the width of each of the plurality of micro-apertures and the thickness of the metal substrate is greater than 2.
22. A dental matrix as claimed in claim 21 wherein the ratio of the width of each of the plurality of micro-apertures and the thickness of the metal substrate is greater than 3.
23. A dental matrix as claimed in any one of claims 1 to 13 wherein each of the plurality of micro-apertures is circular and 20 to 180 micron in diameter. 5
24. A dental matrix as claimed in claim 23 wherein the ratio of the diameter of each of the plurality of micro-apertures and the thickness of the metal substrate is greater than 2.
25. A dental matrix as claimed in claim 24 wherein the ratio of the diameter of each of the plurality of micro-apertures and the thickness of the metal substrate is greater than 10 3.
26. A dental matrix as claimed in any one of claims 1 to 25 wherein the micro- apertures are arranged in a concentric archway pattern. 15
27. A dental matrix as claimed in any one of claims 1 to 25 wherein the micro- apertures are arranged in a honeycomb pattern.
28. A dental matrix as claimed in any one of claims 1 to 26 wherein the plurality of micro-apertures comprises elongate micro-apertures each having a length greater than a 20 width, and at least some of the elongate micro apertures being arranged in concentric rings about a centre or centre region each with its length aligned approximately towards the centre or centre region.
29. A dental matrix as claimed in claim 28, the centre or centre region being located 25 on the dental matrix to be positioned between the lingual side of the tooth and the buccal side of the tooth in use.
30. A dental matrix as claimed in claim 28 wherein the centre or centre region is positioned on the dental matrix, in use the elongate micro-apertures located above the 30 centre each with its length aligned approximately towards the centre or centre region and the elongate micro-apertures located below the centre each with its length aligned approximately horizontally.
31. A dental matrix as claimed in claim 30 wherein the elongate micro apertures 35 located below the centre are arranged in columns.
32. A dental matrix as claimed in claim 28 wherein the centre is located adjacent a bottom edge of the dental matrix.
33. A dental matrix as claimed in any one of claims 28 to 32 wherein the plurality of 5 micro-apertures comprises two groups of micro-apertures, each group of micro-apertures comprising elongate micro-apertures each having a length greater than a width, and at least some of the elongate micro apertures being arranged in concentric rings about a centre or centre region each with its length aligned approximately towards the centre or centre region.
34. A dental matrix as claimed in claim 33 wherein the two groups of micro-apertures are located either side of a centre line of the dental matrix.
35. A dental matrix as claimed in any one of the preceding claims wherein the 15 thickness of the dental matrix is less than 60 micron.
36. A dental matrix as claimed in claim 35 wherein the thickness of the dental matrix is less than 50 micron. 20
37. A dental matrix as claimed in claim 36 wherein the thickness of the dental matrix is less than 45 micron.
38. A dental matrix as claimed in any one of claims 1 to 37 wherein the dental matrix is a sectional matrix.
39. A dental matrix as claimed in any one of claims 1 to 37 wherein the dental matrix is a shaped circumferential band.
40. A dental matrix as claimed in any one of claims 1 to 37 wherein the dental matrix 30 is a straight edged circumferential band.
41. A dental matrix for use in repairing and restoring cavities with light-cured restorative material, the dental matrix comprising: a metal substrate comprising a plurality of micro-apertures, wherein the plurality of micro-apertures comprises elongate micro-apertures each having a length greater than a width, and at least some of the elongate micro apertures being arranged in concentric rings about a centre or centre region each with its length aligned approximately towards 5 the centre or centre region.
42. A dental matrix as claimed in claim 41, the centre or centre region being located on the dental matrix to be positioned between the lingual side of the tooth and the buccal side of the tooth in use.
43. A dental matrix as claimed in claim 41 wherein the centre or centre region is positioned on the dental matrix, in use the elongate micro-apertures located above the centre each with its length aligned approximately towards the centre or centre region and the elongate micro-apertures located below the centre each with its length aligned 15 approximately horizontally.
44. A dental matrix as claimed in claim 43 wherein the elongate micro apertures located below the centre are arranged in columns. 20
45. A dental matrix as claimed in claim 41 wherein the centre is located adjacent a bottom edge of the dental matrix.
46. A dental matrix as claimed in any one of claims 41 to 45 wherein the plurality of micro-apertures comprises two groups of micro-apertures, each group of micro-apertures 25 comprising elongate micro-apertures each having a length greater than a width, and at least some of the elongate micro apertures being arranged in concentric rings about a centre or centre region each with its length aligned approximately towards the centre or centre region. 30
47. A dental matrix as claimed in claim 46 wherein the two groups of micro-apertures are located either side of a centre line of the dental matrix.
48. A dental matrix as claimed in claim 41 wherein the micro-apertures are arranged in a concentric archway pattern.
49. A method of forming a dental matrix for use in repairing and restoring cavities in a tooth with light-cured composites, the method comprising: i) providing a metal substrate, ii) coating a side of the metal substrate with a polymer to form a polymer layer on a side of the dental matrix for contacting the tooth in use, iii) forming micro-apertures in the metal substrate by photo etching a reverse side 5 of the metal substrate without breaking the polymer layer.
50. A method as claimed in claim 49, comprising: iv) filling the micro-apertures with a transparent or semi-transparent resin. 10
51. A method as claimed in claim 50, comprising applying the resin to the metal substrate by an apparatus that simultaneously fills the micro apertures and removes substantially all resin from the reverse side of the dental matrix.
52. A method as claimed in claim 50, comprising applying the resin to the metal 15 substrate by an apparatus that simultaneously fills the micro apertures and leaves a layer of resin on the reverse side of the dental matrix.
53. A method as claimed in claim 51 or 52 wherein the apparatus comprises one or more of a roller and a squeegee or blade like apparatus.
54. A method as claimed in any one of claims 49 to 53, comprising providing a parent metal substrate and subsequently separating the dental matrix from the parent metal substrate. 25
55. A method as claimed in claim 54, comprising photo etching at least a portion of a perimeter of the dental matrix for separating the dental matrix from the parent metal substrate, and separating the dental matrix from the parent metal substrate by breaking the polymer coating at the perimeter of the dental matrix. 30
56. A method as claimed in any one of claims 49 to 55, comprising adding a photo- resistive film to the reverse side of the metal substrate after the coating is added to the metal substrate.
57. A method as claimed in claim 54 wherein the parent metal substrate is a metal 35 strip.
58. A method as claimed in claim 57 wherein the metal strip is provided in a coil, and the method comprises unwinding the metal strip from the coil for the polymer layer to be applied. 5
59. A method as claimed in any one of claims 49 to 58, comprising spraying the polymer onto a surface of the metal substrate, and heating the metal substrate with sprayed polymer in an oven to form the polymer layer on the metal strip.
60. A method as claimed in claim 50, comprising applying the resin to the metal 10 substrate using a squeegee or blade like apparatus for spreading the resin into the apertures.
61. A method as claimed in claim 60, comprising applying the resin to the metal substrate using a squeegee or blade like apparatus for spreading the resin into the 15 apertures and to leave a layer of resin on the reverse side of the dental matrix.
62. A method as claimed in claim 60, comprising applying the resin to the metal substrate using a squeegee or blade like apparatus for spreading the resin into the apertures and to substantially remove all resin from the reverse side of the dental matrix.
63. A method as claimed in any one of claims 49 to 62 wherein the polymer is a fluorocarbon to form a fluorocarbon layer.
64. A method as claimed in claim 63 wherein the polymer is polytetra-fluoroethylene 25 to form a polytetra-fluoroethylene layer.
65. A method as claimed in any one claims 49 to 64 wherein the polymer layer has a thickness of 25 micron or less. 30
66. A method as claimed in any one claims 49 to 65 wherein the resin is one of a fluorocarbon, polytetra-fluoroethylene, a polyester.
67. A method as claimed in any one of claims 49 to 66 wherein the metal substrate is a foil.
68. A method as claimed in any one of claims 49 to 67 wherein the metal substrate is a stainless steel substrate.
69. A method as claimed in any one of claims 49 to 68 wherein the metal substrate has a thickness of 20 – 50 micron. 5
70. A dental matrix substantially as herein described with reference to the accompanying figures.
71. A method for forming a dental matrix as herein described with reference to the accompanying figures. '
Priority Applications (7)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CA2869263A CA2869263C (en) | 2012-04-02 | 2013-03-29 | Dental matrix band |
EP21159034.4A EP3845199A1 (en) | 2012-04-02 | 2013-03-29 | Dental matrix band |
EP13717373.8A EP2833821B1 (en) | 2012-04-02 | 2013-03-29 | Dental matrix band |
PCT/US2013/034546 WO2013151880A1 (en) | 2012-04-02 | 2013-03-29 | Dental matrix band |
US14/389,556 US10441394B2 (en) | 2012-04-02 | 2013-03-29 | Dental matrix band |
EP18207675.2A EP3513763B1 (en) | 2012-04-02 | 2013-03-29 | Dental matrix band |
US16/560,441 US20190388203A1 (en) | 2012-04-02 | 2019-09-04 | Dental matrix band |
Publications (2)
Publication Number | Publication Date |
---|---|
NZ604244A true NZ604244A (en) | 2013-05-31 |
NZ604244B NZ604244B (en) | 2013-09-03 |
Family
ID=
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US20190388203A1 (en) | Dental matrix band | |
US8303302B2 (en) | Systems and methods for orthodontic devices | |
JP4745232B2 (en) | Curable dental article and method for producing the same | |
JP5009434B1 (en) | Nail corrector and nail correction treatment set | |
US20140001664A1 (en) | Matrix band for dental applications | |
LU84840A1 (en) | METHOD AND ARTICLE FOR FACILITATING THE MANUFACTURE OF A METAL BONDING SURFACE | |
JPH04505269A (en) | dental matrix | |
WO2005046503A1 (en) | Method and impression tray for producing a dental mold | |
NZ604244A (en) | Dental matrix band | |
NZ604244B (en) | Dental matrix band | |
CH680563A5 (en) | ||
WO2017211588A1 (en) | Dental restoration production device and add-on or attachment | |
WO2004069077A2 (en) | Dental adhesive strip | |
KR100558075B1 (en) | Burnishing tool for hard skin care, and method for preparation thereof | |
CN205359668U (en) | There are not drawing of patterns hook pincers and drawing of patterns system that ask groove stealth to rescue ware | |
ITMI971267A1 (en) | CONTAINER AND PROCEDURE FOR CROSS-LINKING COMPOSITE MATERIALS ON DENTAL PROSTHESES PARTICULARLY FOR USE WITH LAMPS | |
US6083005A (en) | Method of use of natural latex emulsion | |
WO2013058804A1 (en) | Coating for a dental matrix band | |
Shortall et al. | Microleakage around direct composite inlays | |
JP2019025310A (en) | Corneum removing instrument and manufacturing method thereof | |
JP2008206577A (en) | Adhesive plaster with function for removing wrinkle and fleck on skin and its manufacturing method | |
KR102512463B1 (en) | A device that guides the implant installation location | |
SE516859C2 (en) | Dental technical instrument | |
JP2008291329A (en) | Bridge-less etching product, and method for producing the same | |
JP3097069U (en) | Bracket transfer tray in indirect orthodontic method |