WO2016013992A1

WO2016013992A1 - Self-ligating bracket

Info

Publication number: WO2016013992A1
Application number: PCT/TR2014/000259
Authority: WO
Inventors: Resai AYDIN
Original assignee: Aydin Resai
Priority date: 2014-07-23
Filing date: 2014-07-23
Publication date: 2016-01-28

Abstract

A self-ligating orthodontic bracket (10) consists of a bracket body (12) and a ligating slide (14). Ligating slide (14) is able to move between the open position where the archwire (52) is placed in the archwire slot (16) on the bracket body (12) and the closed position where it can be kept in the archwire slot (16). Ligating slide (14) consists of three arms angled to each other. Outer flexible arms activate once the archwire (52) of a certain thickness is placed in the archwire slot (16) and depress the wire.

Description

SELF-LIGATING BRACKET

FIELD OF THE INVENTION

This invention relates to an orthodontic apparatus used in dentistry and more particularly an apparatus which enables self-ligation. This orthodontic apparatus is an apparatus called bracket and used in order to correct position of the teeth in orthodontic treatment by putting wire between it and bonding it on the teeth.

BACKGROUND OF INVENTION

Self-ligating brackets provide convenience to the dentist applying orthodontic treatment, save time and also enable faster moving of the teeth.

For the tightness of the bracket, through which the archwire is placed, to be adjusted to depress the wire when necessary, the closing method is expected to be convenient and able to apply force actively.

Arch wires are available in quite various forms. While more flexible round wires applying less force are used at the beginning of orthodontic treatment, diagonal wires which can exert torque force on the teeth are used in subsequent stages. There are self- ligating brackets with different mechanisms in order to couple archwire to bracket slot. These brackets are in two types: passive or active. Passive systems keep archwire in the slot passively and do not apply force. In active systems, flexible clip applies force on the archwire after it reaches a certain thickness in self-ligating systems that are known under the available technique. Disadvantage of passive systems is that they cannot control archwire through sufficient compression. Easy moving of archwire in bracket slot is good at the beginning in terms of wire's applying low forces to teeth; however, its failure to provide sufficient compression even though the wire is thickened creates a more uncontrolled force and angles adjusted in the bracket slot at the production stage to direct teeth are not reflected to the teeth at a sufficient level. That is why active systems emerged. In most active systems, force is applied on the archwire with a flexible clip after archwire reaches a certain thickness. However, many problems occurred related to the structure of this clip. Most important of these is the deformations of the clip and second is the problems related to opening-closing mechanism. An extra device is used in both active and passive systems to open or close the mechanism. It is very important that this device functions practically in the mouth and does not cause the dentist to lose time.

Most important disadvantage of self-ligating brackets is the problems related to their opening-closing mechanisms.

The aim in self-ligating brackets is to enable the dentist to lock the bracket by exerting the least effort and using fewest additional instruments.

Features of an ideal orthodontic bonding system are safe and durable coupling, full compliance with the bracket, quick and easy coupling, low friction and compatibility with the comfort and hygiene of the patient. In previous technique, different suggestions were put forward for ligation systems used in self-ligating brackets. One of these is explained in the reference numbered US 5 586 882. Ligating slide of this self-ligating bracket is made of superelastic shape-memory metal alloy. Ligating slide is formed in U-shape, which enables mounting hooks, return springs and other members on it.

However, first disadvantage of this system is that clip goes under the bracket. This increases the profile height of bracket, thus creating a bigger bracket. This is

undesirable in terms of its view and ergonomics. Second disadvantage is keeping thickness of the clip at a certain level to avoid increasing the bracket height further. Applied force decreases due to thin clip. Third disadvantage is the position of the point where it should be applied to open the clip. It may create difficulties in terms of ease of application if it is close to gingiva and in a less visible portion. Another previous technical reference relating to current invention can be US 8 636 507. In the bracket under this patent, ligation cover is provided in a way to fit in recesses within bracket wings. This ligation cover can move between an open position and locking position; while it enables entering archwire slot in open position, it is impossible to access archwire slot in closed position.

However, disadvantage of this previous technical reference relating to self-ligating apparatus is that force to be applied by broad U-shaped clip on the wire is low since it has little resistance and also clip is deformed during opening by being pulled through the hole on it.

In the reference numbered US 2103/0260329 which is another previous technical reference, a locking shutter with flexible arms is described. Locking shutter with flexible arms is designed to fit in the vertical slots in bracket body and according to the provided description, arms move in the upper part of slots in the body and enable decrease and increase in the force on archwire.

However, the disadvantage of the apparatus suggested in this reference is potential problems that may be faced during opening and closing. When side arms going through a narrow slot face a thick angular wire, they will be exposed to distortion and clip will be squeezed. It is very likely that there will be difficulty in opening the clip with the impact of residue and much force will be applied. Another disadvantage is that clip entering and exiting the bracket in an angled way increases profile height of the bracket. High profile means a voluminous and large bracket.

In order to abolish disadvantages of previous technical references described above, a bracket with a self-ligating apparatus is suggested with present invention subject to application.

BRIEF DESCRIPTION OF THE INVENTION

The invention is about a slidable bracket containing a ligating slide. Ligating slide consists of three arms. These three arms are connected to each other with a bar. Side arms are angled with the middle arm in the gingival direction. Thanks to this angle and the rounded shape of the tip of the side arms, the distance between the lowest point of the side arms and the base of the bracket slot is less than the distance between the lowest point of the middle arm and the base of the bracket slot. By this means, while the ligating slide is in the closed position, side arms activate in the transitional stage from the round wire to the angular wire. The lowest point of the side arms is vertically at the very mid-point of the bracket slot base. By this means, when the side arms activate, center of resistance of the angular wires are depressed at the closest point. Middle arm of the ligating slide goes through a bridge on the bracket body and side arms fit in recesses and platforms at the both side of the bridge. Ligating slide and bracket body can be made of different materials. While the ligating slide is in the open position, the archwire is placed in the bracket slot and while it is in the closed position, the archwire is kept inside of the bracket slot. In the light of this information, an orthodontic bracket consisting of a body containing a bonding base to bond to the tooth, one pair of wing placed in occlusal and one pair of wings placed in gingival, gingival and occlusal wings appears from the labial side of the body; an archwire slot goes throughout the body in the mesiodistal direction between the occlusal and gingival wings placed in the distal edges to position the archwire; a ligating slide containing a middle arm between a pair of side arms and an middle arm in the occlusal-gingival direction towards the gingival along with the side arms at an alpha angle, a ligating slide which can move between the open position where the archwire is removed and placed and the closed position where the removal and the placement of the archwire is prevented; a bridge through which the middle arm of the ligating slide goes and moves in the occlusal-gingival direction, a pair of platforms on which side arms are placed on the body in the mesial and distal of this bridge and sockets were provided in a modelling of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The bracket subject to the invention will be described in detail referring to the figures attached. In these figures, Figure 1 is the perspective view of the flexible ligating slide while in the closed position where the archwire is kept inside the archwire slot and invention's modelling of the self-ligating orthodontic bracket.

Figure 2 is the perspective view of the modelling of separated orthodontic bracket which has the ligating slide on the left and the body on the right side.

Figure 3 is the perspective view of the modelling of separated orthodontic bracket which has the ligating slide on the right and the body on the left side.

Figure 4 is the perspective view from the left of the modelling of self-ligating bracket with the ligating slide in open position.

Figure 5 is the perspective view from the different angles according to the figure 5 of the modelling of self-locking bracket with the ligating slide in open position.

Figure 6a is side view of the invention's modelling of self-ligating bracket with the ligating slide in open position inside the body.

Figure 6b is the side view of the invention's modelling of self-ligating orthodontic bracket with the ligating slide in closed position inside the body and the angle archwire in the archwire slot.

Figure 7 is the side view of the active and passive positions of the ligating slide's side arms while the ligating slide is in closed position inside the body portion and the round and square formed archwires are inside the archwire slot.

Figure 8 is the perspective view of the modelling of separated orthodontic bracket which has the ligating slide on the left and the body portion on the right side.

Figure 9 is the side view of the modelling of self-ligating orthodontic bracket while the ligating slide is in closed position inside the body and the angular archwire is inside the archwire slot.

Although this invention is described in relation to the specific modelling, practically it cannot be limited to a specific type of self-ligating orthodontic bracket. The description of the invention's modelling can involve various alternatives, modifications and equal arrangements in the light of scope and content which were stated in the claims.

Especially the ones who are experts at this technique will realize that the parts of this invention's modelling can be arranged in various ways. The numbers of the parts used in the pictures are as following: self-ligating bracket

bracket body portion

ligating slide

16 archwire slot

18 first body portion

19 bonding base

20 second body portion

21 recess between the wings in the first body portion

22a,22b, 22c, 22d body portion wings

23 socket in the first side wall

24 archwire slot first side wall

25 archwire slot base portion

26 archwire slot second side wall

27a, 27b rounded recesses on the support surface

28a,28b platforms on the second body portion

29 slot inside the bridge

30 bridge on the body portion

3 la,3 lb recesses on the side walls of the bridge

32a, 32b legs of the bridge

33 support surface

34 recess between wings on the second body portion

36 bridge stop surface

40 bar connecting the arms of the ligating slide

41 a, 41 b side arms of the ligating slide

42 middle arm of the ligating slide

43 a, 43 b heel portions where arms join the bar

44 protrusion of the middle arm

45 a, 45b rounded leading ends of arms

46 a,46b labial surfaces of outer arms

47 labial surface of middle arm

48 a,48b lowermost points of rounded ends of arms 49 lingual surface of middle arm

50 representative round archwire

52 representative angular archwire

62a, 62b recesses modified on support surface

63a, 63b modified heel portions where the arms connect to the bar

64a, 64b modified ends of arms

Figures 1 and 2 comprise of one orthodontic bracket (10), one bracket body (12), and a movable closure member attached to the bracket body (12). Another embodiment includes a flexible ligating slide (14) connected to the movable closure member bracket body (12) in a sliding fashion. Bracket body (12) includes an archwire slot (16) adapted to receive archwire for the right force to be applied on the teeth. The ligating slide (14) can move between Figure 6A which is the open position where the archwire can be placed in the slot (16) and Figure 6b which is the closed position where the archwire is captured in the slot (16). The bracket body (12) and the ligating slide (14) form together an orthodontic bracket (10) to be used in corrective orthodontic treatment.

Orthodontic bracket (10) is described here by using a reference framework where it is bonded on the labial surface of a tooth from the lower jaw unless otherwise stated. As a result, as in here, terms such as labial, lingual, mesial, distal, occlusal and gingival that are used to describe the bracket (10) are within this chosen reference framework.

Nevertheless, the embodiments of the present invention are not limited to this chosen reference framework and the terms and the orthodontic bracket (10) may be used in various orientations and teeth within the oral cavity. For example, the bracket (10) may be applied on the lingual surface of the tooth while remaining within the scope of the invention. The ligating slide (14), while moving to closed position, may move in gingival direction as described here or may also be applied to the tooth to move in occlusal direction. The bracket body (12), with reference to Figure 3, includes an archwire slot (16), first body portion (18) of the archwire slot (16) in gingival direction and a second body portion (20) in occlusal direction. The archwire slot (16) includes a first sidewall (24) at the first side, a second sidewall (26) at the second side and a bottom wall (25) extending between the first and second sidewalls (24,26). The bracket body (12) includes a bonding base (19) that enables coupling of the bracket (10) with the tooth on the lingual surface.

The second body portion (20) includes a bridge (30) in the middle, a slot (29) in the bridge, a support surface (33) on which bridge (30) legs (32a,32b) are placed, wings (22a,22b) to which various orthodontic apparatus may be coupled when necessary on both mesial and distal sides of the bridge horizontally, a recess (34) between the wings (22a,22b), rounded recesses (27a,27b) on the support surface (33) on the labial portion of the wings and flat platforms (28a,28b) at a different level in lingual direction as opposed to the support surface (33).

The slot (29) provided in the bridge (30) is open at both ends and one of such ends leads towards the slot (16) where the archwire is to be positioned while the other towards the opposite direction of bracket body (12). A stopping surface (36) on which the protrusion (44) of ligating slide (14) at the lingual-facing surface and upper side of the bridge (30) opening to the archwire slot (16), on the portion of the archwire slot (16) leading to the opposite direction, two recesses (31a, 31b) on mesial and distal are provided on which the bar portion (40) of the ligating slide (14) sits on the legs (32a, 32b) of the bridge (30) in closed position.

The ligating slide (12) that forms the other part of the ligating bracket (10) and ensures ligation consists of three arms (41a,41b,42) that are interlinked. Two of such arms (41a,41b) are located on outer sides while the other (42) is in the middle. The link between the arms (41a,4 lb,42) is ensured through their connection to a bar (40) rounded toward the bottom. The is a level difference between lingual surface of heel portions (43a, 43b) of arms (41a,41b) and the lingual surface of the bar (40). A protrusion (44) extending in labial direction on the leading end of middle arm (42) of ligating slide (12) extends longitudinally through the arm (42) as a whole. While the outer arms (41a, 41b) of the ligating slide (14) extend first vertical to the bar (40) in labial direction, they extend downward in gingival direction. The lingual surfaces of leading ends (45a, 45b) of outer arms (41a,41b) are wider and rounded at the ends as opposed to the whole in transversal cross-section of the arm (41). While the outer arms (41a,41b) extend downward in gingival direction to the archwire slot base portion, the middle arm (42) extends parallel. The angle (a) between the labial surfaces (46a,46b) of outer arms (41a,41b) and the labial surface (47) of middle arm (42) is between 5-40 degrees. Most preferable is between 10-20 degrees.

The ligating slide (14) is provided to the end user as connected to the bracket body (12). In closed position (Figure 1), middle arm (42) of ligating slide (12) runs inside the bridge (30) until the first sidewall (24) of archwire slot and engaged on the support surface (33). Heel portions (43a, 43b) where outer arms (41a, 41b) join the bar are positioned in the archwire slot (16) with their leading ends (45a, 45b) on flat platforms (28a, 28b) and their lowermost points (48a, 48b) perpendicular to the middle point of archwire slot base wall. The bar portion (40) of ligating slide (14) engage the recesses (31a, 31b) of the bridge (30) and placed on the support surface (33). When the ligating slide is moving from closed position (Figure 1) to open position (Figure 4) in occlusal- gingival direction, protrusion (44) of middle arm (42) fully engages the stop surface (36) of the bridge (30) (Figure 6a), thereby preventing it from being fully released from bracket body (12). Meanwhile rounded leading ends (45a, 45b) of outer arms (41a,41b) engage the rounded recesses (27a,27b) on support surface (33).

With reference to Figure 6b,7, when the ligating slide (14) is in closed position with the bracket body (12), the distance (dl) between lowermost points (48a,48b) of lingual surfaces of rounded leading ends (45a,45b) of outer arms (41a,41b) and the archwire slot base wall (25) is less than the distance (d2) between the lingual surface (49) of middle arm (42) and the archwire slot base wall (25). The distance (dl) between lowermost points (48a,48b) of lingual surfaces of rounded leading ends (45a,45b) of outer arms (41a,41b) and the archwire slot base wall (25) is less than around 0.025 inch. While the round archwire (50) is in the slot (16) flexible outer arms (41a,41b) are passive and while the angular archwire (52) at a certain thickness is in the slot (16) flexible outer arms (41a,41b) are active. First body portion (18) includes wings (22c,22d) that may be coupled with various orthodontic apparatus when necessary, a recess (21) between these wings (22c,22d) and a socket (23) in the area that is between the wings and is adjacent to first sidewall (24) of archwire slot. A suitable tool, e.g. a mini screwdriver, or a similar tool inserted manually and externally into the socket (23) may be used to move the flexible ligating slide (14) between open and closed positions.

Embodiments describing some modifications of ligating slide (14) and bracket body (12) illustrated in Figures 8,9. According to these embodiments, there is no level difference between the lingual surfaces of heel portions (63a,63b) of side arms

(41a,41b) of ligating slide (14) and the lingual surface of the bar (40) they are coupled. They fit on the support surface (33) of corresponding second bracket body (12) in closed position. There are no flat platforms (28a,28b) with a level difference amongst each other in lingual direction on the support surface (33). Lingual surface of leading ends (64a,64b) of side arms (41a,41b) of ligating slide (14) are flattened, and only the connecting portion to the labial surface is rounded. Rounded recesses (62a,62b) on support surface (33) that correspond in open position are shaped to be aligned to the leading end (64a,64b) of side arms (41a,41b). A self-ligating orthodontic bracket with a flexible ligating slide, in accordance with the principles of the invention, may be made using any suitable material and manufacturing technique. The material to make the said ligating slide may be manufactured of any material; e.g. the bracket body may be of stainless steel, translucent aluminum oxide or a polymer-based material (i.e., a plastic), and the ligating slide may be made of a titanium alloy, a nickel/titanium alloy or a polymer-based material (i.e., a plastic),. Ligating slide may be manufactured at the same time by using different types of materials. For example, middle arm (42) of ligating slide (14) may be manufactured of stainless steel while the outer flexible arms (41a,41b) of nickel titanium. Arms of ligating slide (14) may be manufactured at varying flexibility.

Claims

CLAIMS 1. A self-ligating bracket (10) consisting of one or more arms (41a, 41b, 42) that can move between positions to depress and release archwire as desired when archwire is present in archwire slot (16) provided in said bracket body (12), comprising of at least one ligating slide (14) where at least one of the arms fit in slot (29) provided in bracket body (12);

containing an archwire slot (16) comprising a slot base wall (25) extending between first slot side wall (24), second side wall in the second side (26) first and second slot side walls (24,26), comprising at least one first body portion in gingival side (18) of archwire slot (16) at least one second body portion in occlusal side (20), a bracket body (12) with at least one bridge (30) providing at least one slot (29) and at least one bonding base ensuring bonding to tooth on lingual surface in said second body position (20) of said bracket body portion.

2. Self-ligating bracket in Claim 1 (10) comprising minimum one socket (23) in the section neighbouring first side wall (24) of archwire slot (16) and falling between wings (22c,22d) of a recess (21) in occlusal side between wings (22c, 22d) of said first body portion (18).

3. Self-ligating bracket in Claim 1 (10) comprising one or more wings (22a,22b) on which orthodontic apparatus can be mounted when desired in horizontally mesial and distal side of said bridge (30) in said second body portion (20) and one or more recesses (27a, 27b) rounded on support surface in labial side (33) and one or more flat platforms (28a, 28b) between which there is level difference according to support surface (33) of said second body portion (20).

4. Self-ligating bracket (10) of Claim 1 wherein both leading ends of slot (29) provided in the said bridge (30) are open, while one of such leading ends is open at the side of the slot (16) wherein the archwire is to be placed and the other is open at the other side of bracket body (12).

5. Self-ligating bracket (10) of Claim 1 wherein the said ligating slide (14) includes at least three arms (41 a,41b,42).

6. Self-ligating bracket (10) of Claim 1 wherein the said bracket body (12) and the said ligating slide (14) are uniformly configured.

7. Self-ligating bracket (10) of Claim 4 wherein the said slot (29) extends transversely through the said bridge (30).

8. Self-ligating bracket (10) of Claim 1 wherein the said bracket body (10) and^the said ligating slide (14) are configured to prevent their disengagement yet to allow their aligned movements.

9. Self-ligating bracket (10) of Claim 1 wherein when the said ligating slide (14) is in closed position with the bracket body (12), the distance (dl) between lowermost points (48a,48b) of lingual surfaces of rounded leading ends (45a,45b) of outer arms (41a,41b) and the archwire slot base wall (25) is less than the distance (d2) between the lingual surface (49) of middle arm (42) and the archwire slot base wall (25).

10. Self ligating bracket (10) of claim 1 wherein a stop surface (36) into which the protrusion (44) of the ligating slide (14) at the upper side of said bridge (30) opening to the archwire slot (16) and on the lingually facing surface, at the closed position, at the direction facing opposite to the archwire slot (16) the legs (32a, 32b) of said bridge (30) the bar portion (40) of the said ligating slide (14) is engaged into one or more recesses (31a, 31b) provided in mesial and distal directions.

1 1. Self-ligating bracket (10) of Claim 5 wherein complete disengagement from bracket body (10) is prevented through fitting the protrusion (44) on middle arm (42) of ligating slide (14) on the stop surface (36) of body portion (12).

12. Self-ligating bracket (10) of aforementioned Claims wherein while the round archwire (50) is used in the said archwire slot (16) outer arms (41a,41b) are passive and while the angular archwire (52) is in the slot (16) outer arms (41a,41b) are active.

13. Self-ligating bracket (10) of Claim 5 wherein said outer arms (41a, 41b) have more flexibility as opposed to the middle arm (42).

14. Self-ligating bracket (10) of Claim 5 wherein said arms (41a,41b,42) extend in differing angles as opposed to each other and as opposed to said body portion (12).

15. Self-ligating bracket (10) of Claim 5 wherein outer arms (41a,41b) of said ligating slide (14) extend in labial direction first at a straight angle to the bar (40) then extend downward in gingival direction.

16. Self-ligating bracket (10) of Claim 5 wherein the angle (a) between the labial surfaces (46a, 46b) of outer arms (41a, 41b) of said ligating slide (14) and the labial surface (47) of middle arm is between 5 to 40 degrees.

17. Self-ligating bracket (10) of Claim 16 wherein the angle (a) between the labial surfaces (46a, 46b) of outer arms (41a, 41b) of said ligating slide (14) and the labial surface (47) of middle arm is between 10 to 20 degrees.

18. Self-ligating bracket (10) of Claim 5 wherein one or more of leading ends of said arms (41a,41b,42) are rounded.

19. Self-ligating bracket (10) of Claim 1 wherein the bar portion (40) of said ligating slide (14) is engaged in the recesses (31a, 31b) of said bridge (30) and fit on said support surface (33) and when the ligating slide is moving from closed position to open position in occlusal-gingival direction, protrusion (44) of middle arm (42) fully engages the stop surface (36) of the bridge (30) (Figure 6a), thereby preventing it from being fully released from bracket body (12), while rounded leading ends (45a, 45b) of outer arms (41a, 41b) fit on the rounded recesses (27a, 27b) on support surface (33).

20. Self-ligating bracket (10) of Claim 5 wherein there is no level difference between the lingual surfaces of heel portions (63a,63b) of side arms (41a,41b) of said ligating slide (14) and the lingual surface of the bar (40) they are coupled.

21. Self-ligating bracket (10) of Claim 5 wherein lingual surfaces of leading ends (64a, 64b) of side arms (41a,41b) of said ligating slide (14) are flattened, and only the connecting portion to the labial surface is rounded,

22. Self-ligating bracket (10) of Claim 3 wherein rounded recesses (62a,62b) on support surface (33) that correspond in open position to leading ends (64a, 64b) of side arms (41a, 41b) of said ligating slide (14) on the said second body portion are shaped to be aligned to the leading end (64a,64b) of side arms (41 a,4 lb).

23. Self-ligating bracket (10) of above Claims wherein said ligating slide (14) may be moved between open and closed positions by using a manual tool externally into the said socket (23).