CROSS REFERENCE TO RELATED APPLICATION This application incorporates by reference United States Patent Application Serial Number Application 10/238,295 as originally filed on October 23,2002, by the same inventors.

BACKGROUND OF THE INVENTION A matrix band is a common tool used in dentistry.

Typically, the matrix band is a thin, flexible piece of material. Generally speaking, the matrix band is metallic in nature. A dentist will position the band around a tooth to be filled. The band is then tightened around the tooth, with a clamping device, in order to form a mold or an appropriate support for applying a filling material to the tooth.

Another device used in dentistry, for a purpose similar to that of a matrix band, is a separating strip. The main difference between a matrix band and a separating strip is in the material used. The separating strip is usually formed from a plastic strip. The plastic must be flexible and pharmaceutically acceptable, and may be transparent, translucent, or opaque. Generally, the separating strip is adhered to at least one tooth, rather than being wrapped around and clamped to the tooth as with a matrix band. Thus, it is clear that the matrix band may be also a plastic sheet material. The preferred of such materials is a polycarbonate sheet polymer,

commonly under the registered trademark MYLAR@, available from E. I. Dupont Chemical Company of Wilmington, Delaware.

The matrix band of the prior art is metallic, comprising stainless steel. The matrix band must be substantially impervious to, or not reactive with, fluids in a person's mouth. The matrix band must also be made of a metal that is nontoxic. Because the use of a dental matrix band is well defined in United States Patent Number 5,586, 883 to Nakisher and Uditsky, incorporated herein by reference, the use thereof need not be further defined.

There are a number of different dental matrix bands or devices currently on the market; Universal Adult Matrix Band (available in sizes of 0.0015 inch and 0.002 inch); Adult Molar Matrix Band; Child Matrix Band; and Auto Matrix System.

Although the matrix band is a common and long- used dental implement, problems do exist with the currently used technology. Firstly, capillary action between the matrix band and the tooth causes at least one body fluid, to dampen or contaminate the surface of the tooth being filled. This is extremely undesirable since the presence of an undesirable fluid in the area interferes with the adhesion of the cavity filling material to the tooth, and causes deterioration of the cavity filling material.

Typically, body fluids do interfere with this work. Such body fluids include, but are not limited to, blood and saliva. Interference is caused between the tooth and the filling material, because the best adherence of a filling to a tooth occurs when the tooth is dry, and the mechanical strength of the filling material is maximized.

Another difficulty with a matrix band of the prior art is the tendency of the bands to adhere to the cavity filling material. This adherence may make the matrix band difficult to remove from the tooth,

when the filling process is complete, and may require the dentist to exert extra force on the patient's mouth in order to remove that matrix band. A difficult removal of the matrix band may well be uncomfortable for the patient, and weaken the bond between the cavity filling material and the tooth.

Without a good bonding between filling material and the tooth, the dental procedure is ineffective.

Still another difficulty of currently utilized matrix bands is the flat surface of the bands, which contain no indentations where a dental instrument can be used to grasp the band to assist in removing the band after the cavity has been filled. This makes the removal of the band more difficult.

Many devices are known in the prior art, which allegedly permit easy removal of a matrix band from a tooth. One attempt to solve the problem included making the matrix band with a gold plating. However, this gold-plated matrix band does not completely solve or eliminate the ingress of fluid, which causes an undesired body fluid flow into the desired work area.

While it is not desired to be bound by any particular theory, the capillary action is believed to occur because the solid gold or gold alloy matrix band, as well as the gold- plated matrix band is not soft enough to form a seal with the tooth, thereby failing to eliminate the ingress of fluid due to capillary action.

Also, the separating strip suffers from problems caused by the presence of body fluids present because of capillary action or other sources between the separating strip and the tooth. Although the separating strip is formed from a plastic strip, it is not flexible enough to form a seal tight enough to eliminate the fluid.

While polymer coatings can successfully form a seal with the tooth, the adherence of the polymer to the matrix band or the separating strip for dental

purposes is often defective. If the coating does not properly adhere to the matrix band, the effectiveness of the entire band is severely compromised.

SUMMARY OF THE INVENTION Among the many objectives of this invention is the provision of a dental matrix band seal in combination with a matrix band, the matrix band being coated with a suitable polymer, which at least minimizes the ingress of fluid between the matrix band and the tooth, by creating a seal which keeps the surface of the tooth dry during the filling process.

Another objective of this invention is the provision of a dental matrix band seal in combination with a matrix band with at least one aperture on the band to assist in the removal of the band from the tooth when the filling procedure is completed.

Yet another objective of this invention is the provision of a dental matrix band seal in combination with a matrix band, which is nontoxic to the patient.

Still another objective of this invention is the provision of a dental matrix band seal in combination with a matrix band, with a polymer coating thereon.

A further objective of this invention is the provision of a dental matrix band seal in combination with a matrix band, with a soft metal coating thereon.

Yet, a further objective of this invention is the provision of a dental matrix band seal in combination with a matrix band, with a coating strongly adhered thereon.

A still further objective of this invention is the provision of a dental matrix band seal in combination with a matrix band.

Also, a further objective of this invention is the provision of a dental matrix band seal in combination with a matrix band, which eliminates the ingress of fluid due to capillary action. or other means.

Still a further objective of the is invention is

the provision of a separating strip with a flexible coating, which eliminates the ingress of fluid due to capillary action or other means.

These and other objectives of the invention (which other objectives become clear by consideration of the specification, claims and drawings as a whole) are met by providing a dental matrix band seal in combination with a matrix band for use in dentistry, wherein the matrix band has a polymer coating or a soft metal applied to an etched surface, which reduces or eliminates capillary action between a tooth and the matrix band, while at least one aperture in the matrix band assists with removal of the matrix band from the tooth.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 depicts a perspective view of a straight coated matrix band 100 with a strip polymer 120 of this invention.

Figure 2 depicts a plan view of a straight coated matrix band 100 with a strip polymer 120 of this invention.

Figure 3 depicts a cross-sectioned view of the straight coated matrix band 100 of this invention along Line 3-3 and based on Figure 2.

Figure 4 depicts a cross-sectioned view of the straight coated matrix band 100 based on Figure 2 around tooth 110.

Figure 5 depicts a perspective view of the straight coated matrix band 100 with spots group 140 of this invention.

Figure 6 depicts a side view of a straight coated matrix band 100 with spots group 140 of this invention.

Figure 7 depicts a cross-sectioned view of straight coated matrix band 100 of this invention along Line 7-7 and based on Figure 6.

Figure 8 depicts a top, plan view of straight coated matrix band 100 of this invention based on

Figure 6.

Figure 9 depicts a rear perspective view of a winged coated matrix band 200 with a flange 160 of this invention.

Figure 10 depicts a front perspective view of a winged coated matrix band 200 with a flange 160 of this invention.

Figure 11 depicts a side view of a winged coated matrix band 200 with a flange 160 of this invention.

Figure 12 depicts a cross-sectioned view of winged coated matrix band 200 with a flange 160 of this invention along Line 12-12 and based on Figure 1, 1.

Figure 13 depicts a top, plan view of winged coated matrix band 200 of this invention based on Figure 9.

Figure 14 depicts a perspective yiew of a plain, elliptical coated matrix band 300 with full polymer strip 170 of this invention.

Figure 15 depicts a side view of a plain, elliptical coated matrix band 300 with full polymer strip 170 of this invention.

Figure 16 depicts a cross-sectioned view of plain, elliptical coated matrix band 300 of this invention along Line 16-16 and based on Figure 15.

Figure 17 depicts a top, plan view of plain, elliptical coated matrix band 300 of this invention based on Figure 14.

Figure 18 depicts a front perspective view of an apertured elliptical coated matrix band 400 with centered discontinuous strip 470 of this invention.

Figure 19 depicts a full front view of an apertured elliptical coated matrix band 400 with centered discontinuous strip 470 of this invention.

Figure 20 depicts a cross-sectioned view of apertured elliptical coated matrix band 400 of this invention along Line 19-19 and based on Figure 18.

Figure 21 depicts a top, plan view of apertured

elliptical coated matrix band 400 of this invention based on Figure 17.

Throughout the figures of the drawings, where the same part appears in more than one figure of the drawings, the same number is applied thereto.

DESCRIPTION OF THE PREFERRED EMBODIMENTS With the matrix band or separating strip of this invention being suitable for use in dental procedures and having a coated surface thereon, capillary action between the tooth and the band is at least substantially reduced, if not eliminated. The coated surface has a soft coating at least partially covering the same.

The concept disclosed and claimed herein may be described as a dental matrix seal and is applicable to any dental matrix device, regardless of the geometric shape of the dental matrix device. The geometric shape of the seal is irrelevant to the function of the seal. The dental matrix seal is made of any material, whether metal or plastic; which has a soft malleable consistency and is applied as a coating to any dental matrix device. Clearly both the soft metal coating and the soft plastic coating are preferably pharmaceutically acceptable. The seal may also be made of flexible ceramic or composites of metal or ceramic. The matrix seal may also be applied as a laminate or tape instead of a coating.

Adhesion of the coating as dental matrix seal to any dental matrix device is assured by etching the surface of the dental matrix device. Etching of the matrix band may be accomplished in any suitable fashion. Acid etching and photochemical etching are specially suitable processes for etching the matrix band, as long as the procedures are pharmaceutically acceptable. Pharmaceutically acceptable includes those materials suitable for use in a person's mouth.

Additionally, the matrix band may be etched by

using mechanical abrasion. Mechanical abrasion may be obtained by subjecting the metal surface to a high velocity stream of silica particles or soft metal particles, or by rubbing the surface with a silica or diamond encrusted paper or metal sheet. Clearly, any abrasive system may be used.

The preferred method of applying coating, laminate or tapes to the separating strip is by using a pharmaceutically acceptable adhesive, but any other suitable method may be used.

Coatings with a thickness of about 0.001 millimeter to about 0.25 millimeter are adequate to reduce the capillary action. Coatings with a thickness of about 0.01 millimeter to about 0.2 millimeter reduce the capillary action more effectively. Coatings with a thickness of 0.02 millimeters to about 0.1 millimeters is most effective in reducing, if not eliminating, the capillary action.

Acid etching preferably occurs in a pharmaceutically acceptable acid at a pH of 4 to 6.

More preferably, the pH is 4.2 to 5.9. Most preferably, the pH is 4.4 to 5.7. Below these pH ranges in a more acidic etching solution, the surface of the dental matrix device is compromised and cannot be made suitable for dental use. Above these pH ranges in a more basic etching solution, the surface of the dental matrix device is etched insufficiently so that a durable coating cannot be applied thereto and cannot be made suitable for dental use.

The etching acid can be any pharmaceutically acceptable acid having a pH in the desired range.

Acetic acid, phosphoric acid, citric acid, hydrochloric acid and suitable mixtures thereof in the desired pH range are quite useful. This etching process is quite acceptable for the purposes of this invention.

A second etching process that may be used is

photochemical etching. Photochemical etching appears to be the preferable method. Appropriate tests are run to determine if the matrix band is suitable for the coating process. After proper inspection, the matrix band is degreased and rinsed. The standard acid wash, followed by appropriate scrubbing and drying, is the final step for the inspection of the matrix band. A photo resist coating is bonded to the surface of the matrix band under a controlled temperature. A controlled ultraviolet light exposure is selectively applied to at least one selected area of the photo resist coating in order to polymerize certain sections thereof.

The unexposed matrix band coating is removed by a standard development system. This developing system dissolves the unexposed areas of the photo resist coating. Washing and cleaning then follows. The exposed parts of the matrix band are then etched with an acid on both sides thereof, if desired. A desired coating is applied to the etched surfaces.

The etching parameters are adjusted empirically as desired. An alkaline wash removes the remaining photo resist coating. The part is then recovered, and one achieves the desired coated matrix band of this invention.

Prior to this invention, one must conclude that, the silicones, siloxanes or adhesives cannot be successfully applied to the matrix band to create a seal. In an attempt to reduce the costs, while maintaining or improving desired results with the design of the above referenced co-pending patent application having the tin applied to the dental matrix band, the successful and micro-mechanically attached tin makes the dental matrix band much more efficient.

The process of photo etching the stainless steel matrix band causes microscopic pits in the surface thereof. With a rolling of the two materials together

after the photo etching, a micro-mechanical bond between the matrix band and the desired coating is achieved. This process can be adapted to the use of silicones and adhesive materials in order to successfully attach the seal or coating to the dental matrix band.

If desired, at least one aperture may be put in the matrix band. Such an aperture; situated in the central portion of a long edge of the matrix band, with the clamp between the aperture and the tooth around which the matrix band is placed; is used to assist with the removal of the band from the tooth.

This can be accomplished with the standard dental tool commonly known as the explorer.

Referring now to the drawings, the following references to specific drawing figures are intended to illustrate without unduly limiting the invention disclosed herein. The polymer coated matrix band of this invention is a result of the etching treatments of the metallic matrix band prior to coating with the desired polymer.

Considering now Figure 1, Figure 2, Figure 3, and Figure 4, the straight coated matrix band 100 has a support base 114 with a strip polymer 120 applied thereto. The strip polymer 120 is applied after the support base 114 is etched. Strip polymer 120 may have a rectangular cross section 122, although other suitable geometric shapes may be used. Band apertures 124 facilitate applying of the straight coated matrix band 100 to a tooth 110 (Figure 4) or removing the same therefrom.

Support base 114 has a first wing 116 and a second wing 118 distinguish by a wing angle 126 therebetween. Each of band apertures 124 are in the support base 114 and outside the strip polymer 120.

Strip polymer 120 may also have tapered sides 130 and a trapezoidal cross section 132. Strip polymer 120 forms a continuous or substantially continuous coating

for the support base 114.

Considering now Figure 5, Figure 6, Figure 7, and Figure 8, the straight coated matrix band 100 has spots group 140. Spots group 140 serves to form an effective discontinuous coating for the coated matrix band. Each spot in spots group 140 may be an appropriate, pharmaceutically acceptable polymer, or an appropriate, pharmaceutically acceptable metal.

Within spots group 140 may be at least one generally circular shape 142, at least one generally triangular shape 144, at least one generally rectangular shape 146, or at least one generally U- shape 148. Such shapes are a matter of choice both in number and type. Each shape may have a tapered side 150. The structure appears between straight coated matrix band 100 and the tooth 110, and supplies necessary sealing qualities.

Further versions of winged coated matrix band 200 appear in Figure 9, Figure 10, Figure 11, Figure 12 and Figure 13, a flange 160 appears on a top portion of winged coated matrix band 200. Below the flange 160, the winged coated matrix band 200 has a triangular section 162 with an arm 164 of the triangular section 162 being adjacent to the winged support base 214. Most preferably, triangular section 162 is substantially a right triangle. Below flange 160 on the winged support base 214 of the winged coated matrix band 200 is a complete triangulated coating 166 having a coating aperture 168 concentric with flared base aperture 224. Triangulated coating 166 extends down winged support base 214.

Still further versions of plain, elliptical coated matrix band 300 appear in Figure 14, Figure 15, Figure 16, and Figure 17, plain, elliptical coated matrix band 300 provides a full polymer strip 170 centrally located along the length of elliptical support base 314. Such a full polymer strip 170 also operates as a sealing mechanism. Clearly, full

polymer strip 170 may be metallic, polymeric, polymer composites of metal or ceramic or flexible ceramics.

Another version of apertured elliptical coated matrix band 400 appears in Figure 18, Figure 19, Figure 20, and Figure 21, apertured elliptical coated matrix band 400 provides a centered discontinuous strip 470 located along the length of elliptical apertured support base 414 adjacent to concentric strip aperture 172. This concentric strip aperture 172 provides an appropriate removal mechanism for the apertured elliptical coated matrix band 400.

Clearly here also, centered discontinuous strip 470 may be metallic, polymeric, polymer composites of metal or ceramic or flexible ceramics.

In the following examples, which are intended to illustrate without unduly limiting the invention disclosed herein, all parts and percentages are by weight, unless otherwise specified.

EXAMPLE ONE With the straight coated matrix band 100 ; having a strip polymer 120 is applied onto a stainless steel support base 114 etched in an acetic acidic solution having a pH of 5.5, the strip polymer 120 being based on a pharmaceutically acceptable siloxane polymer.

That straight coated matrix band 100 is applied to a tooth 110 under repair, where the coating provided a seal that prevented the ingress of fluid into the area of the tooth being repaired.

EXAMPLE TWO The procedure of Example One is repeated except that the etching solution is phosphoric acid and has a pH of 5.0. The coating adheres as well as in Example One.

EXAMPLE THREE The procedure of Example One is repeated except that the etching solution has a pH of 4.7. The coating adheres adequately but is not as durable as the coating set forth in Example Two.

EXAMPLE FOUR The procedure of Example One is repeated except that the etching solution has a pH of 6.2. The coating fails to adhere as in Example One.

EXAMPLE FIVE The procedure of Example One is repeated except that the etching solution has a pH of 4.0. The integrity of the support base 114 is compromised in that matrix is of insufficient strength to fit around tooth 110.

EXAMPLE SIX The procedure of Example One is repeated except that the acid etching process is replaced with the photo etching process. The coating adheres and provides an effective dental straight coated matrix band 100.

EXAMPLE SEVEN The procedure of Example One is repeated except that the acid etching process is replaced with the mechanical abrasion process utilizing a high velocity stream of silica aimed at the surface of the band to etch the surface. The coating adheres and provides an effective dental straight coated matrix band 100.

EXAMPLE EIGHT The procedure of Example Seven is repeated except that the acid etching process is replaced with the mechanical abrasion process utilizing a high velocity stream of soft metal particles aimed at the surface of the band. Such action forms a micro alloy on the surface. The coating forms and provides an effective seal that prevented the ingress of fluid into the area of the tooth being repaired.

EXAMPLE NINE The procedure of Example One is repeated except that the acid etching process is replaced with the mechanical abrasion process involving the buffing of the matrix band's surface with a silica or diamond encrusted sheet to etch the surface of the matrix

band. The coating adheres and provides an effective seal that prevented the ingress of fluid into the area of the tooth being repaired.

EXAMPLE 10 A procedure as described by Gettings and Kinlock"Surface Characterization and adhesives Bonding of Stainless Steals II-the Steal/Adhesive Interface" ; Surface and Interface Analysis Vol. 1 No. 6, p. 189-195, 1979, is used to provide a primer coating to the dental matrix band device.

The stainless steel dental matrix band is degreased by immersion in trichloromethane, followed by warm methanol, followed by a distilled water rinse. The stainless steel dental matrix band was etched in a 30% (v/v) solution of sulphuric acid at 60° C. The band is etched for a time long enough to remove 80g of metal per square meter, which is approximately five minutes. The band is then treated in a solution of twelve to fifteen percent (v/v) sulfuric acid and two percent (v/v) sodium dichromate at 60° C for four minutes. The band is then rinsed with warm water. The treated surface of the dental matrix band is coated with a one percent (v/v) aqueous solution of silane-based primer such as gamma glycidoxypropyltrimethoxy silane containing an equal volume percent of amine curing agent such as tri-z-ethyl hexanote of 2,4, 5- tris (dimethylaminomethyl) phenol. The primed surface then is coated with a polymer to provide a more tightly bound seal coating for the dental matrix bond. Acceptable primers include but are not limited to: polyurethanes, acrylates, saran and polyvinyl chloride.

This application; taken as a whole with the abstract, specification, claims, and drawings being combined; provides sufficient information for a person having ordinary skill in the art to practice the invention as disclosed and claimed herein. Any

measures necessary to practice this invention are well within the skill of a person having ordinary skill in this art after that person has made a careful study of this disclosure.

Because of this disclosure and solely because of this disclosure, modification of this method and device can become clear to a person having ordinary skill in this particular art. Such modifications are clearly covered by this disclosure.

What is claimed and sought to be protected by Letters Patent is: