US3477128A - Method and apparatus for improved orthodontic bracket and arch wire technique - Google Patents

Description

. Noy. .11, 1969 L. F. ANDREWS 3,477,128

Filed Sept. 22. 1967 METHOD AND APPARATUS FOR IMPROVED ORTHODONTIC BRACKET AND ARCH WIRE TECHNIQUE 3 Sheets-Sheet l (PRIOR ART) I INVENTOR. LAWRENCE 'fi ANDREWS Nov. 11, 1969 .F. ANDREWS 3,477,128

METHOD AN P AT FOR IMPROVED ORTHODONTIC BR ET AND CH WIRE TECHNIQUE Filed Sept. 22'. 19s? 3 Shets-Sheet 2 INVENTOR. LAWRENCE E ANDREWS Nov. 11. 1969 .F. ANDREWS 3,477,123

METHOD AND AP ATUS FOR IMPROVED ORTHODONTIC BRACKET AND ARCH WIRE TECHNIQUE Filed Sept. 22, 1967 3 Sheets-Sheet 5 FIG. I7

INVENTOR.

' LAWRENCE f. ANDREWS "wmjziz w United States Patent O M 3,477,128 METHOD AND APPARATUS FOR IMPROVED ORTHODONTIC BRACKET AND ARCH WIRE TECHNIQUE Lawrence F. Andrews, 1808 Cable St., San Diego, Calif. 92107 Filed Sept. 22, 1967, Ser. No. 669,919 Int. Cl. A61c 7/00 U.S. Cl. 3214 11 Claims ABSTRACT OF THE DISCLOSURE The method and apparatus for improving orthodontic bracket and arch wire technique where the individual brackets have an inner radius for attachment to a tooth band which conforms to the outer contour of the tooth both vertically and horizontally and has a groove therein for the reception of an arch wire having a radius for conforming to overall arch wire .geometry and wherein the groove is cut with a torquing angle, a tipping angle, an in-out dimension and in some cases, a rotation compensation angle for cooperation with an unbent arch wire in which the various angles built into the bracket result in desired force vectors for movement of individual teeth to a desired position.

, DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for improved orthodontic bracket and arch wire technique and more particularly to a method and apparatus for an improved orthodontic bracket and arch wire technique in which force vectors are built into the individual orthodontic brackets for obviating the necessity of placing bends in the arch wire to produce the desired force vectors and, hence, the desired tooth movement.

PRIOR ART The prior art method of installing orthodontic brackets and arch wirescomprise basically the placement of brackets on bands which are placed on the patients teeth, each bracket having a groove built therein for the re- 'ception of the arch wire. The orthodontist would then mount the arch wire in the individual bracket grooves and place bends in the arch wire which would result in various force vectors for moving the individual teeth to their desired positions. These force vectors are required for tipping the teeth toward or away from the adjacent teeth. Torquing the teeth, i.e.,-angulating them toward or away from the centerof the mouth was accomplished by placing a twist in the arch wire 'along its longitudinal axis and moving the teeth in and out parallel to themselves toward the center or away from the center of the mouth and forward and back in dental arch. Other required or desired force vectors would be, as in the case of extractions, compensation for tooth rotation resulting in an attempt to move the tooth toward or away from another toothand tip compensation to avoid the tooth tipping as it is moved toward or away from adjacent teeth. Other'considerations involved in making these complex bends in the arch Wire would be the compensations for the haphazard mounting of the bracket due to the outer contour of the tooth in two directions, i.e., horizontally and vertically, and general arch wire geometry. As can be appreciated, these complex vectors resulted at best in an approximation of the proper bends to be placed in the wire and depended a great deal on the individual orthodontic skill, dexterity and experience of the operator. This problem is magnified in the case of apartnership practice since few operators 3,477,128 Patented Nov. 11, 1969 have sufliciently identical techniques to maintain a continuity of movement where succeeding arch wiresare installed by diflerent operators. This, of course, caused considerable jiggling of teeth, i.e., partial retracing of previous movement together with the disadvantages attendant therewith, such as root resorption.

BACKGROUND OF THE INVENTION According to the invention, the ,bracket for each individual tooth has a plurality of dimensons built in which, when coupled to an unbent arch wire, result in the desired force vectors being applied to the tooth. At the present time, there are a total of eight dimensions being taken into consideration. The first two to be considered is the curvature on the band side of the bracket which consists of two radii at right angles to each other, taking into consideration the outer contour of the indivdual tooth since this varies from tooth to tooth, e.g., from a central incisor to a molar. This contour consideration gives meaning to the other builtin force vectors since it supplies a consistent starting point. The prior art haphazard mounting of the bracket to the band results in the absence of this consideration.

The next dimension takes into consideration the arch wire geometry, i.e., the radius of curvature of the arch wire at the point of contact with the individual bracket. The other angles are built into the groove which receives the arch Wire. These angles result in torquing, and tipping forces, and an in-out force. In the extraction case, tip compensation and rotation compensation angles are also built into the arch wire groove. Relative thickness of the bracket from the back side, i.e., the bandside, to the inner face of the groove determines the in-out force.

It has been found that at least 90% of the malocclusions fall into three basic types which can be accommodated by nine basic sets of appliances. These can be subdivided into finer sets taking into consideration extraction and non-extraction cases. With these basic sets, a saving of from 15 to 75 minutes for each arch wire installation is made by each orthodontist, as well as an improved result by removing the guesswork from the installation of the brackets and hands because the built-in angles in the brackets pre-determine their final arrangement.

An object of the present invention is the provision of a method and apparatus for an improved orthodontic bracket and arch wire technique.

Another object is to provide a method and apparatus for improved orthodontic bracket and arch wire technique for providing uniform results regardless of individual skill.

A further object of the invention is the provision of the method and apparatus for improved orthodontic bracket and arch Wire technique which is faster and more uniform in results.

Still another object is to provide a method and apparatus for improved orthodontic bracket and arch wire technique having desired force vectors built into the orthodontic bracket.

Yet another object is to provide a method and apparatus for an improved orthodontic, bracket and arch FIG. 1 is a front elevation view of a typical prior art orthodontic bracket and arch wire installation;

FIG. 2 is a front elevation view of a typical installation of the orthodontic bracket and arch wire technique of the present invention;

FIG. 3 is a top view of a typical prior art ortho dontic bracket and arch wire installation;

FIG. 4 is a top view of a typical installation of the orthodontic bracket and arch wire technique of the present invention;

FIG. 5 is a perspective view of the preferred embodiment of a typical orthodontic bracket according to the present invention;

FIG. 6 is a top view showing a schematic representation of a typical orthodontic bracket and arch wire installation according to the present invention;

menting the set shown and described with reference to FIGS. 6-11. Again, angles A, A, B, B, and D are shown together with radii R, R, R" and dimension C (FIG. 17).

Angles A and A represent torquing angles, Band .B' represent tipping angles and dimension C results in an inout force vector. Radii R and R correspond to the outer contour of the tooth and are at right angles to each other. Radius R conforms to the radius of curvature of the arch wire geometry at that point. The following chart tabulates typical dimensions and angles for a set of these brackets, where dimensions C, R, R and R" are in inches and angles A, A, B, B and D are in degrees. The dimensions and angles shown cover right uppers and left lowers in this exemplary set. The left uppers and right lowers would have the same figures but would constitute a mirror image of the right uppers and left lowers.

A A B B C R R R" D 5.0 5.0 .050 1.00 .50 1.0 9 9.0 9. 0 068 500 50 80 0 10. 8 16.8 .033 .156 1.0 75 0 4. 6 0 037 .156 1. O 75 0 2nd Bicuspid 2. 3 -3. 7 033 156 1.0 40 0 1st Molar 9. 0 4.7 1.3 015 .500 1. 5 .50 0 2nd Molar. 12.0 4. 7 1. 3 023 .500 1. 5 .50 7

A A B B C R R R D Left Lowers:

Central 5.0 2. 4 5. 0 074 187 50 1. 5 0 Lateral 5. 0 2. 4 5. 0 .074 218 50 1. 5 0 Cuspid 10. 5 5. 3 16. 5 045 .187 1.0 75 0 1st Bicuspid- 0 0 025 .156 1.0 50 0 2nd Bicnspid .8 2. 2 020 .140 1.0 0 1st Molar. .6 2. 4 015 500 1. 5 25 7 2nd Molar .6 2. 4 023 500 1. 5 25 9 FIG. 7 is a top view showing a schematic representation of the present invention as applied to an extraction case; and,

FIGS. 8-19 show various views of orthodontic brackets according to the present invention having various corrective force vectors built in as applied to different teeth in a typical case.

Referring to FIGS. 1 and 3, a plurality of teeth is shown each having a tooth band 22 mounted thereon to which an orthodontic bracket 23 is attached. Each orthodontic bracket 23 has a groove which receives arch wire 25. Arch wire 25 has a plurality of bends 26.

Referring to FIGS. 2 and 4, a plurality of teeth 21 is again shown each carrying a tooth band 22. An ortodontic bracket 24 is attached to each tooth band. Each orthodonitc bracket 24 has a groove with a built in angel to effect a smoothly contoured passage of an unbent arch wire 25 therein.

Refering to FIG. 5, an orthodontic bracket 24 has an arch wire groove 27 and a back portion 28 adapted to conform to the contour of a tooth band.

Referring to FIG. 6, a typical patients mouth is shown having central incisors 31, lateral incisors 32, cuspids 33, first bicuspids 34, second bicuspids 35, first molars 36 and second molars 37. Each of these teeth has an orthodontic bracket 24 attached thereto (by a tooth band not shown). Each of said orthodontic brackets 24 has a grOOVe for receiving arch wire 25 therein.

Referring to FIG. 7, an extraction case is illustrated wherein a space generally shown at 41 is to be filled by tooth 42 by moving it parallel to itself toward tooth 43. Here bracket 24 has an angle E built in which compensates for rotation in the direction of arrow 44 and accomplishes a movement of the tooth 42 linearly in the direction of arrow 46. A tipping compensation angle B or B (FIGS. 10, 16, 12 and 18) would also be utilized.

Referring to FIGS. 8-13, typical angles, radii and dimensions are shown on brackets 24 for a patients right upper teeth. These angles are shown as A, A, B, B and D. The radii are shown as R, R and R" and one critical dimension is shown at C (FIG. 11).

Referring to FIGS. 14-19, a group of orthodontic brackets 24 are shown for the left upper teeth comple- It should be understood, of course, that the foregoing r disclosure relates to only a preferred embodiment of the invention and that it is intended to cover all changes and modifications of the examples of the invention herein chosen for the purposes of the disclosure which do not constitute departures from the spirit and scope of the invention.

I claim:

1. An orthodontic bracket comprising:

a bracket having a front face and a back side;

said back side being adapted for mounting to a predetermined tooth having a specific contour, said back side being specifically contoured for cooperation therewith;

said front side having a groove recessed therein for the reception of an arch wire; and the distance from said back side of the bracket to the inner face of said groove conforms to overall curvature of an installed but unbent arch wire geometry.

2. The orthodontic bracket of claim 1 wherein: said rectangular groove has a radius of curvature substantially equal to a predetermined radius of curvature of an unbent arch wire after the complete installation thereof.

3. The orthodontic bracket of claim 1 wherein: said groove has a vertical angle with respect to an axis of a predetermined tooth for creating a predetermined force vector for tipping said predetermined tooth a predetermined amount upon installation of an unbent arch wire.

4. The orthodontic bracket of claim 1 wherein: the distance from said back side-to the inner face of said groove is predetermined to create a predetermined in-out force vector from an installed but unbent arch wire on a predetermined tooth.

5. The orthodontic bracket of claim'l wherein: the outer face of said bracket and the back side of said bracket are angularly displaced a predetermined amount in a vertical plane for creating a predetermined torquing angle force vector on a predetermined tooth from an installed but unbent arch wire.

6. The orthodontic bracket of claim 1 wherein: the outer face of said bracket and the back side of said bracket are angularly displaced a predetermined amount in a horizontal plane for creating a rotating angle force vector on a predetermined tooth from an installed but unbent arch wire.

7. An orthodontic bracket comprising:

a bracket having a front face and a back side;

said front face having a groove recessed therein for the reception of an arch Wire; and

said back side being adapted for mounting to a predetermined tooth, the distance from said back side to the outer face of said bracket conforming to overall curvature of an installed but unbent arch Wire geometry.

8. The orthodontic bracket of claim 7 wherein;

said back side is specifically contoured for cooperation with a predetermined tooth having a specific contour; and

said groove has a vertical angle with respect to an axis of a predetermined tooth for creating a predetermined force vector for tipping said predetermined tooth a predetermined amount after the installation of an unbent arch wire.

9. The orthodontic bracket of claim 7 wherein:

said back side is specifically contoured for cooperation with a predetermined tooth having a specific contour; and

the distance from said back side to the inner face of said groove is predetermined to create a predetermined in-out force vector from a completely installed but unbent arch wire on a predetermined tooth.

10. The orthodontic bracket of claim 7 wherein:

said back side is specifically contoured for cooperation with a predetermined tooth having a specific contour; and

the outer face of said bracket and the back side of said bracket are angularly displaced a predetermined amount in a vertical plane for creating a predetermined torquing angle force vector on a predetermined tooth from a completely installed but unbent arch wire.

11. The orthodontic bracket of claim 7 wherein:

said back side is specifically contoured for cooperation with a predetermined tooth having a specific contour; and

the outer face of said bracket and the back side of said bracket are angularly displaced a predetermined amount in a horizontal plane for creating a rotating angle force vector on a predetermined tooth from a completely installed but unbent arch wire.

References Cited UNITED STATES PATENTS ROBERT PESHOCK, Primary Examiner

Images