Orthodontic Arch Wire Bracket Assembly

Abstract

An orthodontic arch wire bracket assembly for attachment to a tooth band for receiving an elongate arch wire and being characterized by a two-piece assembly which is easy to assemble and disassemble and eliminates the use of conventional tie wires, pins and by-pass clamps. The bracket assembly includes a body member for attachment to a tooth band and having first and second post members extending from the front surface of the body member and protruding outwardly therefrom and being spaced apart to form an orthodontic arch wire bracket receiving channel therebetween. The bracket assembly further includes a retaining member having means at each end thereof for receiving the first and second post members for assembly thereon in such a position that the retaining member spans the channel for holding the arch wires therein. The assembly further includes means for positioning the retaining members on the post members so as to maintain the retaining member outwardly from the body member for maintaining the channel to accommodate the arch wire and means for maintaining the retaining member on the post members.

Description

This invention relates to an orthodontic arch wire bracket assembly for attachment to a tooth band for receiving an elongate arch wire and more specifically to such an assembly characterized by a two-piece assembly which is easy to assemble and disassemble and eliminates the use of conventional tie wires, pins and by-pass clamps.

In orthodontics, the most common method of straightening teeth is by the use of an arch wire which applies a force to a tooth to be straightened by cooperation with a bracket secured to the tooth through a tooth band. The arch wire is anchored to other teeth through suitable brackets and is deflected so as to apply a light force to the tooth to be straightened. The circumferential tooth bands are cemented to the patient's teeth and these bands have brackets spot-welded or otherwise secured to them. The brackets form a channel for reception of an arch wire. This technique requires that the arch wire fit in a channel that has close dimensions to the arch wire itself, but is precise enough so that the arch wire can slide freely with a minimum amount of friction through the channel. The bracket must allow complete freedom of tipping with a minimum of which is in the vertical plane and yet maintain the tooth in the horizontal plane so as to correct rotations of the teeth.

Heretofore, this has been accomplished by the use of tie wires, pins and by-pass clamps which are placed into the brackets and form a definite seat so that the channel is provided for reception of the arch wire and the arch wire is held within the channel. These tie wires, pins and by-pass clamps must be secured manually to the brackets and bent to position on each tooth when a new wire is placed in the bracket. When an arch wire is removed from the bracket, the pin, tie wire or by-pass clamp must be straightened, cut and forceably removed from the bracket. Both the assembly and disassembly, as described above, are tedious processes and loose tie wires, pins and by-pass clamps often become disassembled and fall into the patient's mouth.

Accordingly, it is the object of this invention to provide a two-piece arch wire bracket assembly which is easy to assemble and disassemble and eliminates the use of conventional tie wires, pins and by-pass clamps.

It has been found by this invention that the above object may be accomplished by providing an orthodontic arch wire bracket assembly comprising a body member having a rear surface for attachment to the tooth band and a front surface, and first and second post members each extending from the front surface of the body member and protruding outwardly therefrom to form outer free ends. The post members are spaced apart to form a channel therebetween for receiving the orthodontic arch wire therein. The orthodontic arch wire bracket assembly further includes an elongate retaining member having means at each end thereof for receiving the first and second post members for assembly thereon in such a position that the retaining member spans the channel for holding the arch wire therein. Means are provided for positioning the retaining member on the post members so as to maintain the retaining member outwardly from the body member for maintaining the channel to accommodate the arch wire therein. Means are also provided for maintaining the retaining member on the post members.

This improved orthodontic arch wire bracket assembly provides a two-piece assembly which is preassembled and would be attached to the tooth band in a one step or welding procedure. The bracket assembly eliminates the need for using pins, tie wires and/or by-pass clamps in engaging the arch wire in the bracket. The bracket assembly allows the freedom of tooth movement with a one point contact and is more durable and withstands deformation from the forces of mastication. There is no removal of or replacement of parts of the bracket assembly when making arch wire changes.

Some of the objects and advantages of the invention having been stated, other objects and advantages will appear as the description proceeds when taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a perspective view of a group of teeth having the bracket assembly of this invention thereon for receiving an orthodontic arch wire;

FIG. 2 is an enlarged, exploded perspective view of the body member and post members utilized in the bracket assembly of this invention;

FIG. 3 is a perspective composite view of the members of FIG. 2;

FIG. 4 is a further enlarged perspective view of the tooth band and arch wire bracket assembly of this invention with the retaining member of the assembly exploded;

FIG. 5 is an enlarged perspective view of a single tooth illustrating the arch wire bracket assembly, tooth band and arch wire therein;

FIG. 6 is a cross-sectional view taken generally along the line 6--6 of FIG. 5;

FIG. 7 is a view like FIG. 5 illustrating the use of an orthodontic uprighting spring with the bracket assembly and arch wire;

FIG. 8 is a view like FIG. 4 illustrating an alternative form of the arch wire bracket assembly utilized for arch wires having a generally rectangular cross-section; and

FIG. 9 is a cross-sectional view taken through the arch wire bracket assembly of FIG. 8 in its assembled condition and with an arch wire therein.

Referring now to the drawings, the orthodontic arch wire bracket assembly of this invention is generally referred to by the reference numeral 10. The arch wire bracket assembly 10 is secured by spot-welding or otherwise to a tooth band 11 which fits around a tooth T, as shown particularly in FIGS. 1, 5 and 7, for the purposes described above.

The bracket assembly 10 comprises a body member 12 having a rear surface 13 for attachment to the tooth band B by spot welding or other attachment means (not shown) and a front surface 14. First and second post members 16 and 17 extend from the front surface 14 of the body member 12 and protrude outwardly therefrom to form outer free ends. The post members 16 and 17 are spaced apart to form a channel 18 therebetween for receiving an arch wire W therein.

It has been found by this invention that the body member 12 and post members 16 and 17 may be conveniently constructed from a commercial standpoint by forming the body member 12 of stainless steel which may be stamped or otherwise formed into the particular configuration illustrated in the drawing which provide a channel in the rear surface 13 thereof. The post members 15 and 16 may be formed of glass reinforced resilient nylon material which may be extruded or otherwise formed with the post members 16 and 17 extending from a base portion which fits into the channel in the back of the stainless steel body member so that the post members 16 and 17 extend through apertures in the body member 12 for extending from the front surface 14 of the body member and protruding outwardly therefrom. The post members 16 and 17 and their base are held within the body member 12 by a forced friction fit or otherwise secured therein to form a one-piece body member with protruding post members.

At least one of the post members 16, 17 includes an outer bifurcated end for purposes to be described below.

The bracket assembly 10 further comprises an elongate retaining member 30 which includes transversely-extending apertures 31 and 32 for receiving the ends of the respective first and second post members 16 and 17 for assembly on the post members in such a position that the retaining member spans the channel 18 for holding the arch wire W therein. The retaining member 30 further includes a hollow sleeve 33 extending transversely inwardly from the retaining member 30 and from the aperture 31 so that the sleeve 33 fits over the first post member 16 and forms on surface defining the channel 18 and spaces the retaining member 30 outwardly from the front surface 14 of the body member 12 on the posts 16 and 17 so as to leave the channel 18 open for receiving the arch wire W while spanning the channel 18 to retain the arch wire W within the channel 18.

The retaining member 30 is maintained in the above-described position on the post members 16 and 17 by the bifurcated end of the post member 16. The bifurcated portions of this end of the post member 16 contract when received by the aperture 31 of the retaining member 30 and due to their resilience form a forced fit and hold the retaining member 30 thereon. The bifurcated end of the post member 16 before reception of the retaining member 30 is slightly larger than the aperture 31.

The bracket assembly 10 may also preferably include a transversely-extending slot 40, as shown particularly in FIGS. 4 and 5, for receiving one end of an orthodontic uprighting spring 41, as illustrated in FIG. 7. The other end of the orthodontic spring 41 is conventionally attached to the arch wire W for reasons well known in orthodontics.

The form of the bracket assembly 10 illustrated specifically in FIGS. 1-7 is primarily designed for use with an arch wire W having a generally cylindrical cross-sectional shape and therefore the surfaces defining the channel 18, i.e. the outside surface of the sleeve 33 and the outside surface of the post member 17, are generally cylindrical in shape for forming an arch wire receiving channel 18 having rounded surfaces.

The form of the orthodontic arch wire bracket assembly 10 illustrated specifically in FIGS. 8 and 9 is primarily designed for use with an arch wire W having a generally rectangular cross-sectional shape and therefore the surfaces defining the channel 18, i.e. the surface of the sleeve 33 and the outside surface of the post member 17, are generally flat for providing an arch wire receiving channel 18 having flat surfaces.

The bracket assembly 10 may also include means on one end of the retaining member 30 for reception of elastic bands commonly used in orthodontic tooth correction. In the form of the retaining member illustrated in FIGS. 1-7, the retaining member is somewhat elongated and extends beyond the aperture 31 for forming an outer extension 36 for the reception of the elastic band. Alternatively, instead of the extension 36 shown on the retaining member 30 of FIGS. 1-7, the means for receiving elastic bands may be in the form of winged sections 37 which protrude outwardly from each side of one end of the retaining member 30, as shown in FIG. 8, for the reception of elastic bands.

Thus, it may be seen that this invention has provided orthodontic arch wire bracket assemblies which are characterized by a two-piece assembly which is easy to assemble and disassemble and eliminates the use of conventional tie wires, pins and by-pass clamps. While specific embodiments of a two-piece arch wire bracket assembly in accordance with this invention have been illustrated, it is to be understood that other specific assemblies may be constructed utilizing the novel concepts of this invention.

In the drawings and specification there have been set forth preferred embodiments of this invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

What is claimed is:

1. An orthodontic arch wire bracket assembly for attachment to a tooth band for receiving an elongate arch wire and being characterized by a two-piece assembly which is easy to assemble and disassemble and eliminates the use of conventional tie wire, pins and by-pass clamps, said bracket assembly comprising:

a body member having a rear surface for attachment to the tooth band and a front surface;

first and second post members each extending from said front surface to said body member and protruding outwardly therefrom to form outer free ends, said post members being spaced apart to form a channel therebetween for receiving the orthodontic arch wire therein;

an elongate retaining member having transversely-extending aperature at each end thereof for receiving said first and second post members for assembly thereon in such a position that said retaining member spans said channel for holding the arch wire therein;

means for positioning said retaining member on said post members so as to maintain said retaining member outwardly from said body member for maintaining said channel to accommodate the arch wire therein; and

means for maintaining said retaining member on said post members.

2. An orthodontic arch wire bracket assembly, as set forth in claim 1, in which said means for maintaining said retaining member on said post members comprises a resilient, bifurcated end on one of said post members which is slightly larger than said aperture in said retaining means for converging together when said end of said post member is received in said aperture of said retaining member and for holding said retaining member on said post members by the resilience of said bifurcated end of said post member.

3. An orthodontic arch wire bracket assembly, as set forth in claim 1, in which said bifurcated end on one of said post members comprises glass reinforced nylon.

4. An orthodontic arch wire bracket assembly for attachment to a tooth band for receiving an elongate arch wire and being characterized by a two-piece assembly which is easy to assemble and disassemble and eliminates the use of conventional tie wires, pins and by-pass clamps, said bracket assembly comprising:

a body member having a rear surface for attachment to the tooth band and a front surface;

first and second post members each extending from said front surface of said body member and protruding outwardly therefrom to form outer free ends, said post members being spaced apart to form a channel therebetween for receiving the orthodontic arch wire therein;

an elongate retaining member having means at each end thereof for receiving said first and second post members for assembly thereon in such a position that said retaining member spans said channel for holding the arch wire therein;

means for positioning said retaining member outwardly from said body member for maintaining said channel to accommodate the arch wire therein and comprising a hollow sleeve extending transversely inwardly from one side of said retaining member for being received around one of said post members and thereby forming one surface on said channel; and

means for maintaining said retaining member on said post members.

5. An orthodontic arch wire bracket assembly, as set forth in claim 4, in which said post members and said retaining member are formed from glass reinforced nylon and said body member is formed from stainless steel.

6. An orthodontic arch wire bracket assembly, as set forth in claim 4, in which said retaining member includes means on one end thereof for reception of elastic bands utilized in orthodontic tooth correction.

7. An orthodontic arch wire bracket assembly, as set forth in claim 4, in which said body member defines a transversely-extending slot extending from one side thereof for reception of orthodontic uprighting springs therein.

8. An orthodontic arch wire bracket assembly, as set forth in claim 4, in which the surfaces forming said channel are generally cylindrical for forming a channel for receiving arch wires having a generally cylindrical cross-section.

9. An orthodontic arch wire bracket assembly, as set forth in claim 4, in which the surfaces forming said channel include a generally flat surface for forming a channel for receiving arch wires having a generally rectangular cross-section.