US 3795052 A
A thin flexible sheet insertable uprightly between teeth has a small hole at one end for receiving a pulling instrument and a compound tapering wedge at the opposite end for holding the sheet between teeth. The wedge is shaped such that it not only fixes the matrix between teeth but imparts a bend to the matrix sheet to partly surround the tooth being worked on.
Description (OCR text may contain errors)
United States Patent 1 [111 3,795,052
Mowery Mar. 5, 1974 SELF-SHAPING DENTAL MATRIX 2,152,877 4/1939 Dagavarian 32/63  Inventor: Llewellyn L. Mowery, 1214 Central,
Redands Calif. 92373 Primary ExammerLouis G. Mancene Assistant Examiner.l. Q. Lever Filed! J 1972 Attorney, Agent, or FirmWilliam Jacquet Gribble  Appl. No.: 259,460  ABSTRACT 52 US. Cl. .Q 32/63 A thin flexible Sheet insertable uprightly between 5 A61c 5/12 teeth has a small hole at one end for receiving a pull-  Field of Search 32/63 ing instrument and a Compound tapering wedge at the opposite end for holding the sheet between teeth. The 5 R f Cited wedge is shaped such that it not only fixes the matrix UNITED STATES PATENTS between teeth but imparts a bend to the matrix sheet to partly surround the tooth being worked on. 3,108,377 10/1963 Meyer 32/63 2,891,313 6/1959 Crowley 32/63 3 Claims, 7 Drawing Figures SELF-SHAPING DENTAL MATRIX BACKGROUND OF THE INVENTION The invention relates to dental matrices for forming a wall between teeth being filled and more particularly to such matrices capable of fabrication at such low cost as to be disposable. The general field of the device is shown by US. Pat. No. 3,636,631 entitled Teeth- Separating Wedges For Use During Drilling Operations, issued Feb. 1, 1972 to Benjamin F. Tofflemire.
Frequently teeth deteriorate in the contact area between teeth. In order successfully to repair the deteriorated area the tooth must be drilled out to eliminate the decayed material and to form a retaining socket for the filling amalgam. It is desirable during the filling operation to separate the teeth in the manner illustrated by the Tofflemire patent. It is also desirable to shield the adjacent tooth from the filling material by a matrix wall. The invention therefore is aimed at providing a self-shaping dentral matrix which not only separates adjacent teeth but forms an enveloping wall in the situs of the filling. Preferably such matrices should be so low in fabrication cost that re-use is not economically required and thus eliminate the necessity forexpensive matrix sterilization and re-use.
SUMMARY OF THE INVENTION The invention contemplates a disposable self-shaping dental matrix which comprises a flexible strip, which may be metallic, with attachment means on the strip for receiving a tool, and wedge means on the strip. The wedge means may be both an anchoring element and a contouring means for the strip. Preferably the wedge and contouring means is a protuberance applied to the strip and diminishing in mutually perpendicular directions from a corner of the strip opposite the attachment means. An alternate embodiment of the invention contemplates the protuberance as a .hollow convexity in the face of the strip which may be formed by stamping.
By utilizing stainless steel strips on the order of 0.00 1 -inch thickness to which a plastic material may be applied to form the protuberance, the matrices may be not only self-shaping but also disposable. By using a simple aperture opposite the wedge protuberance, a conventional elongate dental tool may be used as an attachment device for drawing the matrix between teeth.
These and other advantages of the invention are apparent from the following detailed description and drawing.
BRIEF DESCRIPTION OF THE DRAWING FIG. I is a schematic plan view of the teeth of the lower jaw with matrices between adjacent teeth;
FIG. 2 is an elevational view of two adjacent teeth separated by a matrix in accordance with the invention;
FIG. 3 is an elevational view of a preferred matrix of the invention;
FIG. 4 is a plan view of the matrix of FIG. 3;
FIG. 5 is an end elevation of the matrix of FIG. 3;
FIG. 6 is a sectional elevation taken along line 6--6 of FIG. 4; and
FIG. 7 is a sectional elevation similar to FIG. 6 of a further alternate embodiment of the invention.
In the various Figures like reference characters are used for like parts.
DESCRIPTION OF THE PREFERRED EMBODIMENTS In FIG. 1 the incisors 10 of the lower jaw and the ca nines 11 are schematically illustrated, as are the bicuspids 12, the molars 13 and the wisdom teeth 14. A matrix 16 in accordance with the invention is shown drawn into place between bicuspid l2 and molar 13 by a schematically represented dental tool 18. A second matrix 19 in accordance with the invention is shown between the two bicuspids 12. A filling situs 21 is shown in molar 13 adjacent the matrix. The matrix comprises a strip 22 which may be a stainless steel band with a thickness of 0.001 inch with a compound tapering wedge 24. As the tool 18 pulls the matrix between the teeth, the strip tends to become concave (n the side with the wedge and thus forms a wall which partially surrounds the situs 21 of the filling.
The approximate vertical orientation of the matrix 16 is shown in FIG. 2 with the contact between the wedge 24 and the tooth 13 being illustrated.
Matrix 19 of FIG. I is shown prior to its final location between the teeth with its wedge 24 not yet in contact with the bicuspid 12. The matrix may be easily manipulated by a device such as dental tool 18 for removal once its function at the situs of the filling is fulfilled.
In FIGS. 3-6 a matrix 27 comprises a strip 28 which may be of any resiliently flexible material such as metal or plastic. The strip has a circular aperture 29 at one upper corner which serves as an attachment means to the tool used to manipulate it within the mouth. The wedge 24, as can be seen from FIGS. 3, 4 and 5, is fuller near its outer bottom edge 31. The projection of the wedge from the strip diminishes vertically to coincidence with the plane of the strip at upper point 32, and horizontally to coincidence at lower point 33. While the transition lines between the various full and thin projections of the wedge from the surface of the strip have been shown as curving, the invention does not preclude straight line warped surfaces for the wedge. Epoxy materials and others, like substances that become solid but plastic upon final setting to accommo date the bending ofthe matrix strip, may be used to form the protuberance. The wedge 24 of the embodiment of FIG. 3 has proven to'be effective not only to secure the matrix between teeth, but also to induce shaping the strip into a concave wall between the teeth adjacent the filling situs.
The alternate embodiment of FIG. 7 has a flexible strip 28 and a convex wedge 35 which has a hollow 36. The wedge 35 protrudes beyond the plane of strip 28 in the same manner as the wedge 24 of the previously described embodiment. However, the wedge is formed, as by stamping, from the material of the matrix and both the wedge and the attachment means hold, such as the hole 29 of FIG; 3, may be formed in a single stamping operation when the matrix is formed from a continuous strip of material.
The illustrative embodiments show the utility and ease of application of the matrix within the mouth of a patient. The matrix not only gives partial separation to adjacent teeth at the situs of the filling but effects a wall to contain the fill material until it hardens.
In view of the disclosure herein, variations within the scope of the invention other than those shown herein .will occur to those skilled in this particular art. It is therefore desired that the invention be measuredby the appended claims, rather than by the illustrative cmbodiments .digzlosed herein.
I claim? 1. A disp'osable dental matrix comprising a flexible strip, attachment means on the strip located near a cornet of said strip, a tapering protuberance on the strip diminishing in mutually perpendicular directions from a corner of the strip opposite to the attachment means I so protuberance comprises a hollow convexity in the face of the strip.