SELF-LIGATING BRACKET FOR ORTHODONTICS

Abstract

A self-ligating bracket for orthodontics, includes: a groove for receiving an archwire; a slide which can be displaced between a closed position in which it bridges the groove and an open position in which the groove is open; and means which can hold the slide both in its closed position and in its open position. These means contain, in the gingival and/or in the occlusal wall, a recess which is open towards the slide and in which a locking element is inserted which is directed against the slide. The locking element is displaceably guided in the recess and has elastically or elastomerically bendable tines which, when the slide is pushed over the convex end of the locking element, are displaced deeper into the recess, thereby being elastically or elastomerically bent and thereby building up a restoring force.

Claims

1. A self-ligating bracket for orthodontics, comprising: a base; an occlusal wall extending from the base; a gingival wall extending from the base; a groove, which separates the occlusal wall and the gingival wall from each other, and continuously extends in a mesial to a distal direction; a slide, which has a labial side and a lingual side, and is held in a guide provided in the occlusal wall and/or in the gingival wall, and can be displaced in the gingival-occlusal direction in the guide between a closed position, in which the slide bridges the groove, and an open position, in which the groove is open in a labial direction; and a means that can hold the slide in both its closed position and in its open position; wherein these means comprise, in the gingival wall and/or in the occlusal wall, a recess that is open toward the slide, in which is inserted a locking element, which has a convexly designed labial end protruding from the recess, is directed against the lingual side of the slide, and has a lingual end located in the recess; provided in the slide on its lingual side are a first depression and a second depression, which are arranged in such a way that the convex end of the locking element protruding from the recess engages into the first depression when the slide is in its open position, and engages into the second depression when the slide is in its closed position; wherein the bracket also comprises the following additional features: adjacent to the lingual end of the locking element, there is a free space in the recess; the locking element is guided in the recess so that it can be displaced back and forth in a lingual-labial direction, and has one or more elastically or elastomerically bendable tines, which have an end facing in a labial to lingual direction, and glide onto a wall of the recess surrounding the locking element as the locking element is displaced back and forth; wherein the recess tapers in the labial to lingual direction, wherein the recess and locking element are compatible with each other in terms of their shape and position in such a way that, when the slide is pushed over the convex end of the locking element, thereby forcing the locking element out of the first or second depression and deeper into the recess, at least one of the tines in the tapering section of the recess is deflected by the wall, on which it glides deeper into the recess, and is elastically or elastomerically bent.

2. A self-ligating bracket for orthodontics, comprising: a base; an occlusal wall extending from the base; a gingival wall extending from the base; a groove, which separates the occlusal wall and the gingival wall from each other, and continuously extends in the mesial to distal direction; a slide, which has a labial side and a lingual side, and is held in a guide provided in the occlusal wall and/or in the gingival wall, and can be displaced in the gingival-occlusal direction in the guide between a closed position, in which the slide bridges the groove, and an open position, in which the groove is open in a labial direction; and a means that can hold the slide in both its closed position and in its open position; wherein these means comprise, in the gingival wall and/or in the occlusal wall, a recess that is open toward the slide, in which is inserted a locking element, which has a convexly designed labial end protruding from the recess, is directed against the lingual side of the slide, and has a lingual end located in the recess; provided in the slide on its lingual side are a first depression and a second depression, which are arranged in such a way that the convex end of the locking element protruding from the recess engages into the first depression when the slide is in its open position, and engages into the second depression when the slide is in its closed position; wherein the bracket is characterized by the following additional features: adjacent to the lingual end of the locking element, there is a free space in the recess; the locking element is guided in the recess so that it can be displaced back and forth in a lingual-labial direction, and has two elastically or elastomerically bendable tines, which have an end facing in a labial to lingual direction, and glide onto a wall of the recess surrounding the locking element as the locking element is displaced back and forth; the recess tapers in the labial to lingual direction, wherein the recess and locking element are compatible with each other in terms of their shape and position in such a way that, when the slide is pushed over the convex end of the locking element, thereby forcing the locking element out of the first or second depression and deeper into the recess, the tines in the tapering section of the recess are deflected by the wall, on which they glide deeper into the recess, are elastically or elastomerically bent, and thereby inevitably moved closer together.

3. The bracket according to claim 1, wherein the recess tapers continuously.

4. The bracket according to claim 1, wherein the recess has a closed lingual end.

5. The bracket according to claim 1, wherein the recess has a constant cross section in an area adjacent to the slide, and tapers thereafter.

6. The bracket according to claim 1, wherein the recess has a rectangular cross section and tapers like a wedge.

7. The bracket according to claim 6, wherein the first depression and the second depression have a rectangular outline on the lingual side of the slide.

8. The bracket according to claim 1, wherein the recess has a circular cross section and conically tapers.

9. The bracket according to claim 8, wherein the first depression and the second depression have a circular outline on the lingual side of the slide.

10. The bracket according to claim 1, wherein two tines arranged like a fork are provided on the locking element.

11. The bracket according to claim 10, wherein the tines can be moved closer to each other by pressing the locking element deeper into the recess by exerting pressure on its convex end, during which one tine or both tines are bent by sliding on a wall in the tapering section of the recess.

12. The bracket according to claim 11, wherein the two tines are mirror-inverted identical in design.

13. The bracket according to claim 1, wherein the locking element has an arch-like body, which consists of two mutually parallel running tines, and a head section that connects them, which carries the convex end of the locking element.

14. The bracket according to claim 1, wherein the locking element has outer edges that are provided with a chamfer.

15. The bracket according to claim 1, wherein the tines have inclined surfaces or conical surfaces that face the adjacent wall surface of the recess at their ends.

16. The bracket according to claim 15, wherein the inclined surfaces or conical surfaces run parallel to the adjacent wall surface of the recess in the relaxed state of the locking element.

17. The bracket according to claim 1, wherein a stop is provided on the body of the bracket, which prevents the slide from being displaced beyond the closed position while being moved from its open position into its closed position.

18. The bracket according to claim 17, wherein the stop is provided on the gingival wall.

19. The bracket according to claim 1, wherein at least the contour of the second depression is adjusted to the contour of the convex end of the locking element.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Illustrative embodiments of the invention are shown in the attached drawings. The same or corresponding parts are labeled with matching reference numbers in the embodiments.

[0037] FIG. 1 shows an oblique view of a bracket according to the invention, wherein the slide and the locking element are removed;

[0038] FIG. 2 shows a detail of the locking element on FIG. 1 on a magnified scale relative to FIG. 1;

[0039] FIG. 3 shows the bracket of FIG. 1 after insertion of the locking element and before insertion of the slide;

[0040] FIG. 4 shows a section though the bracket with the slide in its closed position, wherein the section is centrally placed through the locking element in a plane at a right angle to the arrow on FIG. 3;

[0041] FIG. 5 shows an oblique view of the bracket, with the slide in its closed position;

[0042] FIG. 6 shows the bracket in a section lying in the same plane as the section on FIG. 4, but with the slide in a position between the closed position and the open position;

[0043] FIG. 7 shows a section through a longitudinal central plane of the bracket parallel to the two guides of the slide;

[0044] FIG. 8 shows, in a schematic, oblique view of a detail of the bracket cut in the displacement direction of the slide, a modification of the bracket depicted on FIGS. 1 to 7, in which the locking element is predominantly cylindrical in design, and the lower side of the slide is adjusted thereto, with the slide in its closed position;

[0045] FIG. 9 shows a section of the detail depicted on FIG. 8, wherein the locking element is also cut, with the slide in its closed position;

[0046] FIG. 10 shows a section as on FIG. 9, with the slide in an intermediate position between the open position and the closed position; and

[0047] FIG. 11 shows a section as on FIG. 9, with the slide in its open position.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0048] The bracket shown in FIGS. 1 to 7 has a concavely curved base 1, whose curvature is approximated to the front side of a tooth. On its lower side 2 forming the lingual side of the bracket, the base 1 has depressions 3 arranged in rows with approximately a rectangular cross section. An adhesive can be applied to the lower side 2 to bond the bracket onto a tooth. In this way, the adhesive meshes with the depressions 3.

[0049] The base 1 passes over into a socket 4, on which stand a gingival wall 5 and an occlusal wall 6. The two walls 5 and 6 run parallel to each other, and are separated by a groove 7, which in orthodontic parlance is also referred to as “slot”, runs continuously straight from distal to mesial, and is labially open.

[0050] The gingival wall 5 is provided with a ligature wing 8 projecting in the gingival direction. A ligature wing 9 projecting in an occlusal direction is provided on the occlusal wall 6. Ligature wires can be secured thereto in a manner known to the expert. The ligature wings 8 and 9 can alternatively be divided into a respective pair of correspondingly smaller ligature wings, which lie one next to the other in a distal to mesial direction. The ligature wing has a hook-shaped extension 9a, which has no importance relative to the present invention. The invention is suitable both for brackets with such an extension 9a, and for brackets without such an extension 9a.

[0051] The groove 7 is used to receive an archwire, which is not part of the bracket, and thus not shown. Tensioning the archwire makes it possible to exert pressure on the base 10 of the groove 7 and a torque on the walls 5 and 6 of the bracket.

[0052] A labial recess 14 in the gingival wall 5 and a labial recess 15 in the occlusal wall 6 receive a primarily flatly designed slide 13 with an essentially rectangular outline. The recesses 14 and 15 have mutually parallel undercuts 11 and 12 that run occlusal to gingival, which together with the base 17 of the recess 15 and the base 20 of the recess 14 comprise sliding guides for the slide 13, which the slide 13 cannot exit in a labial direction, because the undercuts 11 and 12 prevent this. The recesses 14 and 15 lie in a shared alignment. The recess 14 passes through the occlusal wall 6, whereas the recess 15 in the gingival wall 5 ends at a stop, which is the “second” stop 18 mentioned in the claims.

[0053] The slide 13 can be displaced back and forth in the gingival-occlusal direction in the guide formed by the recesses 14 and 15 as well as by the undercuts 11 and 12 between an open position in which the slide 13 is held only in the occlusal wall 6, and a closed position shown on FIGS. 5 to 7. In the open position, the groove 7 is labially open across the full width. In the open position, the front end 19 of the slide 13 preferably closes with the surface of the occlusal wall 6 bordering the groove 7. In the closed position, the front end 19 of the slide 13 hits the second stop 18 on the gingival wall 5, as shown especially clearly on FIG. 7. In the closed position, the slide 13 bridges the groove 7, so that an archwire running therein cannot exit the groove 7 in a labial direction.

[0054] A slit-shaped recess 21 is located in the occlusal wall 6, which extends primarily parallel to the surface of the occlusal wall 6 bordering the groove 7. The opposing surfaces 21a and 21b of the recess 21 that extend in the direction of the groove 7 run parallel to each other, see FIG. 7. The wall surfaces 21c and 21d running at a right angle to the surfaces 21a and 21b as well as at a right angle to the groove 7 run parallel to each other in a section adjacent to the labial edge 21e of the recess 21. In a section adjoining the latter, the wall surfaces running perpendicular to the surfaces 21a and 21b are no longer parallel to each other, but rather arranged at an acute angle to each other, and are thus here referred to as wedge surfaces 21f and 21g. They close the recess 21 before reaching the lower side 2 of the bracket, meaning that the recess 21 tapers like a wedge in this section, as illustrated on FIGS. 4 and 6. The locking element 22 shown on FIG. 2 is inserted in the recess 21, and is movably guided back and forth therein in the labial-lingual direction between the position shown on FIG. 4 and the position shown on FIG. 6.

[0055] The locking element 22 has a convex, labial end 22a, which in the present illustrative embodiment is shaped like a section of a cylinder jacket surface. This is adjoined by an arch-like body 23, which can have chamfers 24 on its outer edges for easier introduction into the recess 21. The arch-like body 23 consists of two mutually parallel running tines 25 and a head section 26 that connects them, which carries the convex end 22a of the locking element 22. The lingual ends 22b of the tines 25 have inclined surfaces 27, whose inclination coincides with the inclination of the wedge surfaces 21f and 21g. In a relaxed state of the kind shown on FIGS. 2 and 4, the inclined surfaces 27 of the locking element 22 thus lie completely on the wedge surfaces 21f and 21g of the recess 21, see FIG. 4, which shows the state with the slide 13 in its closed position. As depicted on FIGS. 2 and 4, the two tines 25 are arranged like a fork, and designed to match the wedge surface 21f and 21g in the lingually tapered direction.

[0056] The locking element 22 consists of a material, in particular of a plastic, which is elastically or elastomerically deformable. Therefore, the tines 25 can be moved closer to each other through exposure to outside pressure. The outside pressure can be applied by pressing the locking element 22 deeper into the recess 21 by exerting pressure on its convex end 22a. As a result, the inclined surfaces 27 of the tines 25 slide in a lingual direction, i.e., in the direction toward the lower side 2 of the bracket, and are thereby inevitably moved closer together through bending, as depicted on FIG. 6, which shows the state in which the slide 13 is located in a position between the closed position and the open position. The tines 25 can be moved closer together because a free space is present between the two tines 25 due to the arch-like shape of the body 23, as depicted on FIGS. 2, 4 and 6, as well as on FIGS. 8 to 11.

[0057] In the closed position as depicted on FIG. 7, the convex end 22a protrudes over the edge 21e of the recess 21 by the largest possible measure. The entire cylinder jacket surface at the convex end 22a is here located above the edge 21e, and is located in a cylinder jacket-shaped second depression 28 on the lower side (lingual side) of the slide 13. The second depression 28 and the convex end 22a of the locking element 22 enter into a positive-locking fit in this position, which secures the closed position of the slide 13.

[0058] In order to move the slide 13 out of the closed position into its open position, the slide 13 is pressed toward the right in line with the illustration on FIG. 7, which can be done by having a plunger engage into a depression 16 provided in the upper side (in the labial side) of the slide 13. As a result of the rightward pressure exerted on the slide 13 in line with FIG. 7, the latter exerts a downwardly directed pressure on the locking element 22 in the area of the second depression 28, so that the latter is pressed deeper into the recess 21, wherein a restoring force builds up in the tines 25. A low projection 29 adjoins the second depression 28 on the lower side of the slide 13. Once it has glided onto the convex end 22a of the locking element 22, the locking element 22 has reached its deepest point in the recess 21, as shown on FIG. 6. As shown on FIG. 7, the low projection 29 separates the first depression 30 and the second depression 28 from each other. As shown on FIG. 7, the low projection 29 can be deepened relative to the edge areas 37 and 38 of the lingual side of the slide 13, but less deepened than the first depression 30 and the second depression 28.

[0059] The low projection 29 is adjoined by a flat recess on the lower side of the slide 13, which ends at a stop 25. The flat recess involves a “first depression” 30 mentioned in claim 1. When the slide 13 glides onto the locking element 22 with its first depression 30, the latter can spring back out of the recess 21 by a measure determined by the distance between the lingual surface of the projection 29 and the floor of the first depression 30. This results in an engagement between the convex end 22a of the locking element 22 and the first depression 30, which holds the slide 13 in its open position. The first depression 30 serves only to prevent the slide 13 from inadvertently returning to its closed position. This safeguard need not be as reliable as the safeguard for the closed position, since the open position is only required during the treatment of a patient in orthopedic practice. By contrast, the closed position is better secured, because it is intended to prevent the slide from inadvertently 13 opening outside of orthodontic practice, in particular while chewing foods or gum, and thereby allow an archwire lying in the groove 7 to slide out.

[0060] A stop 31 on the lower side of the slide 13 that borders the first depression 30 prevents the slide 13 from being lost from the open position.

[0061] FIG. 8 shows a cutout from the occlusal wall 6 of a bracket of the kind shown on FIGS. 1 to 7, wherein a cut is made through the longitudinal central plane of a section of the slide 13. The longitudinal central plane is here understood as the plane that centrally cuts the slide 13, and runs at a right angle to the longitudinal extension of the slot 7, and also cuts the base 10 of the slot 7 at a right angle (see FIG. 7).

[0062] The change relative to the example shown on FIGS. 1 to 7 lies in the fact that the locking element 22 is essentially a cylindrical body, which is slit from the lingual end to form two tines 25, and continues toward the labial end in a truncated cone 34, whose tip 22a, the labial end of the locking element 22, is a circular area.

[0063] The locking element 22 is inserted in a borehole 36 with a cylindrical section and an adjoining conical section.

[0064] Adjusted to this shape of the locking element 22, the first depression 32 and the second depression 33 in the lingual side of the slide 13 are conical in design.

[0065] As in the first illustrative embodiment, the slide 13 is guided in two undercuts, of which only one undercut 12 is shown on FIGS. 8 to 11 owing to the selected section.

[0066] FIGS. 8 and 9 show the slide 13 in its closed position, in which the truncated cone 34 of the locking element 22 engages into the conical second recess 33, whose opening angle coincides with the opening angle of the truncated cone 34.

[0067] FIG. 10 shows the slide 13 in an intermediate position between its closed position and its open position. In this position, the slide 13 has pressed the locking element 22 deeper into the borehole 36, so that the two tines 25, whose inclined surfaces 27 rested on the conical surface of the borehole 36 in the closed position (FIGS. 8 and 9), were moved closer together at their tips. The projection 29 of the slide 13 lying between the two conical depressions 32 and 33 lies on the labial end 22a of the locking element 22, which presses against the lower side of the extension 29 owing to the bending stress in the tines 25.

[0068] FIG. 11 shows the slide 13 in its open position, in which he conical first depression 32 lies above the borehole 36, and the locking element 22 has reversed the bending of its tines 25, and moved into the first conical depression 32 with its truncated cone 34.

[0069] As opposed to the preceding illustrative embodiment, the two conical depressions 32 and 33 have an identical depth in this embodiment.

REFERENCE LIST

[0070] 1 Base [0071] 2 Lower side, lingual side [0072] 3 Depression [0073] 4 Socket [0074] 5 Gingival wall [0075] 6 Occlusal wall [0076] 7 Groove [0077] 8 Ligature wing [0078] 9 Ligature wing [0079] 9a Hook-shaped extension of the ligature wing 9 [0080] 10 Bottom of groove 7 [0081] 11 Undercut [0082] 12 Undercut [0083] 13 Slide [0084] 14 Labial recess [0085] 15 Labial recess [0086] 16 Depression in 13 [0087] 17 Bottom of recess 15 [0088] 18 Second stop [0089] 19 Front end [0090] 20 Bottom of the recess 14 [0091] 21 Recess for locking element [0092] 21a Surface of the recess 21 [0093] 21b Surface of the recess 21 [0094] 21c Wall surface [0095] 21d Wall surface [0096] 21e Label edge of the recess 21 [0097] 21f Wedge surface [0098] 21g Wedge surface [0099] 22 Locking element [0100] 22a Labial convex end [0101] 22b Lingual end [0102] 23 Arch-like body [0103] 24 Chamfer [0104] 25 Tines [0105] 26 Head section [0106] 27 Inclined surfaces or conical surfaces [0107] 28 Second depression [0108] 29 Projection [0109] 30 First depression [0110] 31 Stop on slide [0111] 32 First conical depression [0112] 33 Second conical depression [0113] 34 Truncated cone [0114] 36 Borehole [0115] 37 An edge area of the lingual side of the slide 13 [0116] 38 An edge area of the lingual side of the slide 13