Patent Publication Number: US-2020281691-A1

Title: Self-ligating orthodontic bracket

Description:
CROSS REFERENCE 
     This application is a division of U.S. application Ser. No. 14/149,585 filed Jan. 7, 2014, which application is a continuation of U.S. application Ser. No. 12/477,824, filed Jun. 3, 2009, now U.S. Pat. No. 8,638,507, issued on Jan. 28, 2014. 
    
    
     BACKGROUND 
     The present invention relates generally to the field of orthodontics and, more specifically, to the field of orthodontic bracket assemblies. 
     According to established orthodontic techniques, it is well-known to attach an orthodontic bracket assembly to a patient&#39;s tooth. The bracket assembly provides a location for attaching an archwire and other orthodontic devices to facilitate movement of the tooth. According to established orthodontic techniques, it is well-known to ligate an archwire to the orthodontic bracket assembly utilizing an elastic or metal ligature. In conventional orthodontic bracket assemblies, the ligature is wrapped around respective gingival and occlusal tie wings so as to overlay the archwire at mesial and distal ends of the orthodontic bracket assembly. 
     Recently, designers have created self-ligating bracket assemblies that do not require a separate ligature for attachment of the archwire to the bracket assembly. One type of self-ligating bracket assembly is supplied with a locking shutter that is movable between an open position, permitting access to the archwire slot, and a closed position, inhibiting access to the archwire slot. Self-ligating bracket assemblies substantially decrease the time involved in performing ligation procedures. 
     SUMMARY 
     The present invention provides a self-ligating orthodontic bracket comprising a body and a locking shutter. The body has an archwire slot defined at least partially by a side surface (e.g., a gingival side surface) and a lingual surface, and a mesio-gingival reference plane is defined tangent to a lingual-most point of the lingual surface. The body further includes an occlusal-gingival opening that intersects the reference plane. The locking shutter is coupled to the body and movable between a closed position where access to the archwire slot is inhibited and an open position where access to the archwire slot is permitted. The locking shutter includes a lingual end located in the opening at a closed lingual location when the locking shutter is in the closed position, and wherein the lingual end is located at an open lingual location when the locking shutter is in the open position. The locking shutter further includes a labial end located at a closed labial location when the locking shutter is in the closed position and at an open labial location when the locking shutter is in the open position, wherein the side surface is closer to the open labial location than to the closed labial location. A first occlusal-gingival distance from the closed lingual location to the open lingual location is at least about 70% of a second occlusal-gingival distance from the closed labial location to the side surface. Preferably, the first occlusal-gingival distance is at least about 80%, and more preferably at least about 90%, of the second occlusal-gingival distance. 
     In one embodiment, the body further includes a lingual resting groove in which the lingual end of the locking shutter is positioned when the locking shutter is in the open position. In this embodiment, the resting groove is positioned outside of the occlusal-gingival opening. 
     In another embodiment, the opening is in a first side of the body, and the body further includes at least one tie wing on the first side of the body. In this embodiment, the locking shutter is substantially free of contact with the tie wing when the locking shutter is in the open position. 
     In another aspect, the present invention provides a self-ligating orthodontic bracket comprising a body and a locking shutter, as generally described above. The body has an archwire slot defined at least partially by a lingual surface, and a mesio-gingival reference plane defined tangent to a lingual-most point of the lingual surface. The body further includes an occlusal-gingival opening in a first side of the body and intersecting the reference plane. The body further includes at least one tie wing on the first side of the body. The locking shutter is coupled to the body and movable between a closed position where access to the archwire slot is inhibited and an open position where access to the archwire slot is permitted. The locking shutter includes a lingual end located in the opening at a closed labial location when the locking shutter is in the closed position, and wherein the lingual end is located at an open lingual location when the locking shutter is in the open position. A first occlusal-gingival distance from the closed lingual location to the open lingual location is at least about 60% of a second occlusal-gingival distance from the closed lingual location to an end of the tie wing. Preferably, the first occlusal-gingival distance is at least about 65%, and more preferably at least about 70%, of the second occlusal-gingival distance. 
     Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a self-ligating orthodontic bracket. 
         FIG. 2  is another perspective view of the self-ligating orthodontic bracket of  FIG. 1 . 
         FIG. 3  is a perspective view of the self-ligating orthodontic bracket of  FIG. 1  with a locking shutter removed. 
         FIG. 4  is a top view of the self-ligating orthodontic bracket of  FIG. 1 . 
         FIG. 5  is a section view of the self-ligating orthodontic bracket of taken along the section-line  5 - 5  in  FIG. 4 . 
         FIG. 6  is a side view of the self-ligating orthodontic bracket of  FIG. 1 . 
         FIG. 7  is a section view of the self-ligating orthodontic bracket taken along the section-line  7 - 7  in  FIG. 6 . 
         FIG. 8  is a section view, similar to the section view of  FIG. 7 , of a different self-ligating orthodontic bracket embodying aspects of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein is for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless specified or limited otherwise, the terms “mounted,” “connected,” “supported,” and “coupled” and variations thereof are used broadly and encompass both direct and indirect mountings, connections, supports, and couplings. Further, “connected” and “coupled” are not restricted to physical or mechanical connections or couplings. 
     The following description will refer to  FIGS. 1-7 , each including a reference axis with four or more reference directions. The reference directions are labeled  1 - 6  as follows: a labial direction  1 , a lingual direction  2 , a distal direction  3 , a mesial direction  4 , an occlusal direction  5 , and a gingival direction  6 . The illustrated reference directions are intended to clarify the description and do not in any way limit the scope of the invention. In other embodiments, the reference directions may be other than are shown or arranged differently. 
       FIG. 1  illustrates a self-ligating orthodontic bracket assembly that includes a bracket  14  and a locking shutter  18 . The bracket  14  has a closed position (broken lines in  FIGS. 5 and 6 ) in which the shutter  18  inhibits access to an archwire slot  22  and an open position ( FIGS. 1, 2, 4 , and solid lines in  FIGS. 5 and 6 ) in which the shutter  18  allows access to the archwire slot  22 . 
     The illustrated bracket  14  includes a body  26  and a base  30 . The illustrated body  26  includes the archwire slot  22 , two receiving areas  34 , a first tie wing  38 , a labial resting groove  42 , a second tie wing  46 , a lingual resting groove  50 , and an occlusal-gingival opening  54 . The illustrated base  30  connects the bracket  14  to a tooth (not shown) and includes an attachment portion  58  that defines a pattern (see  FIG. 3 ) which receives an adhesive and is shaped to affix to the tooth. In the illustrated embodiment, the lingual side of the attachment portion  58  affixes to the labial side of the tooth. In the illustrated construction, the base  30  is attached to the body  26  with welds. In other constructions, the base  30  may be attached in other ways or formed as a single piece with the body  26 . 
     The illustrated archwire slot  22  is defined by a lingual surface  62 , a gingival side surface  66 , and a occlusal side surface  70  (see  FIG. 2 ). In the illustrated embodiment, a mesio-gingival reference plane  72  (see  FIG. 5 ) is tangent to a lingual-most point of the lingual surface. The archwire slot  22  receives an archwire (not shown) and inhibits movement of the archwire in the lingual, gingival, or occlusal directions. 
     The illustrated receiving areas  34  are defined in a gingival portion  74  of the body  26  and include a first receiving area  78  separated from a second receiving area  82  by a protrusion  86 . The first receiving area  78  extends labially and gingivally from the gingival side surface  66  to a retention lip  90  on one of the mesial or distal sides of the body  26 . The second receiving area  82  extends labially and gingivally from the gingival side surface  66  to the retention lip  90  on the other of the mesial or distal sides of the body  26 . The protrusion  86  separates the first receiving area  78  and the second receiving area  82  mesio-distally and is gingivally even with the gingival side surface  66 . 
     The illustrated first tie wing  38  is formed on the gingival portion  74  of the body  26  and provides a place for ligation bands or wire to be wrapped for functional or aesthetic purposes. The first tie wing  38  includes two wings although less that two wings or more than two wings are possible. 
     The illustrated second tie wing  46  is formed on an occlusal portion  94  of the body  26  and provides a place for ligation bands or wire to be wrapped for functional or aesthetic purposes. The second tie wing  46  includes one wing although more than one wing and less than one wing have been considered. 
     The illustrated labial resting groove  42  is defined as a lingually-depressed area in the occlusal portion  94  of the body  26 . The labial resting groove  42  is engaged by the shutter  18  while in the open position. In other constructions, the labial resting groove  42  may be other shapes or may be removed. 
     The illustrated lingual resting groove  50  is defined as a labially-depressed area in the occlusal portion  94  of the body  26 . The lingual resting groove  50  is engaged by the shutter  18  while in the open position. In other constructions, the lingual resting groove  50  may be other shapes or may be removed. 
     The illustrated occlusal-gingival opening  54  is defined in the occlusal portion  94  of the body  26 , extends gingivally into the occlusal portion  94  of the body  26  from an occlusal side  98 , and is positioned such that the mesio-gingival reference plane  72  intersects the occlusal-gingival opening  54 . The occlusal-gingival opening  54  is sized to receive the shutter  18  when in the closed position. 
     With continued reference to  FIG. 1 , the illustrated shutter  18  includes a labial portion  102 , an intermediate portion  106 , and a lingual portion  110 . The labial portion  102  is substantially the same mesio-distal width as the body  26  and includes a labial end  114 , a notch  118 , and a cut-out  122 . 
     The illustrated labial end  114  of the shutter  18  is curved labially to form a convex surface  126  that fits in the labial resting groove  42  when the shutter  18  is in the open position. The notch  118  is defined in the labial end  114  and receives the protrusion  86  when the shutter  18  is in the closed position such that the shutter  18  is stabilized in the mesio-distal direction. In other constructions, the labial portion  102  may be different shapes or mesio-distal widths. In addition, the convex surface  126  and the labial end  114  may be different shapes or may be straight sections. Furthermore, the labial end  114  may define more than one notch  118  or less than one notch  118  and the body  26  may include more than one protrusion  86  or less than one protrusion  86  to be received in the notches  118  in the labial end  114 . 
     The illustrated cut-out  122  is a circle that extends through the shutter  18  and receives a tool (i.e. an opening tool, not shown) that may be used to move the shutter  18  between the open position and the closed position. In other constructions, the cut-out  122  may be different shapes, may not extend through the shutter  18 , or may be removed. 
     The illustrated intermediate portion  106  connects the labial portion  102  to the lingual portion  110  and has a narrower mesio-distal width than the labial portion  102  such that the intermediate portion  106  fits between the two wings of the second tie wing  46 . In other constructions the intermediate portion  106  may have the same mesio-distal width as the labial portion  102  or may have a smaller mesio-distal width. 
     The illustrated lingual portion  110  engages the lingual resting groove  50  while in the open position and includes a lingual end  130  (see  FIGS. 5 and 6 ) that has is shaped labially. The lingual portion  110  is sized to be received within the occlusal-gingival opening  54  and has a smaller mesio-distal width than the labial portion  102 . The illustrated lingual portion  110  has the same mesio-distal width as the intermediate portion  106 , although different mesio-distal widths are possible. 
     Turning now to  FIG. 2 , the bracket  14  is shown with the occlusal side surface  70  illustrated on the occlusal portion  94  of the body  26 . In addition, a slot  134  is illustrated in the occlusal portion  94  that extends occlusally from the occlusal side surface  70  and lingually from a labial face  136 . The slot  134  allows the tool to engage the cut-out  122  such that the tool may move the shutter  18  between the open position and the closed position. 
       FIGS. 5 and 6  illustrate the shutter  18  in the open position in solid lines and in the closed position in broken lines. The occlusal-gingival opening  54  is intersected by a mesio-gingival reference plane defined by the lingual surface  62  of the archwire slot  22 . In the illustrated embodiment, the occlusal-gingival opening  54  does not extend entirely through the bracket  14 , and thus no portion of the opening is positioned directly lingually of the archwire slot  22 . 
     An illustrated distance A is defined by the occlusal-gingival distance between the lingual end  130  in the closed position and the lingual end  130  in the open position. An illustrated distance B is defined by the occlusal-gingival distance between the labial end  114  in the closed position and the labial end  114  in the open position. An illustrated distance C is defined by the occlusal-gingival distance from the lingual end  130  in the closed position to an occlusal edge  138  of the second tie wing  46 . An illustrated distance D is defined by the occlusal-gingival distance between the labial end  114  in the closed position and the occlusal side surface  70 . 
     In the illustrated construction, the distance A is about 1.0 millimeters, the distance B is about 1.2 millimeters, the distance C is about 1.4 millimeters, and the distance D is about 1.1 millimeters. In other constructions the distance A may be between about 0.5 and 2.0 millimeters, the distance B may be between about 0.6 and 2.4 millimeters, the distance C may be between about 0.7 and 2.8 millimeters, and the distance D may be between about 0.5 and 2.2 millimeters. In the open position the lingual end  130  is disposed in the lingual resting groove  50  at an open lingual location and the labial end  114  is disposed in the labial resting groove  42  at an open labial location. In the closed position the lingual end  130  is disposed in the occlusal-gingival opening  54  at a closed lingual location and the labial end  114  is disposed in the receiving area  34  at a closed labial location. 
     In operation, the bracket  14  is attached to the tooth with the attachment portion  58 . The shutter  18  is moved to the open position with the labial end  114  disposed in the labial resting groove  42 , the lingual end  130  disposed in the lingual resting groove  50 , and the shutter  18  is substantially free of contact with the second tie wing  46 . The appropriate archwire is fit into the archwire slot  22 , and the tool engages the cut-out  122  and moves the shutter  18  out of the open position such that the labial end  114  leaves the labial resting groove  42  and the lingual end  130  leaves the lingual resting groove  50 . The shutter  18  is moved over the archwire and into the closed position such that the labial end  114  is disposed within the receiving area  34  and the lingual end  130  is disposed within the occlusal-gingival opening  54 . Once in the closed position, the shutter  18  inhibits the archwire from moving in the labial direction such that the archwire slot  22  and the shutter  18  cooperate to inhibit the movement of the archwire in the labial, lingual, occlusal, and gingival directions. 
     To remove the archwire, the tool is engaged with the cut-out  122  and the shutter  18  is moved from the closed position to the open position such that access is provided to the archwire slot  22  and the archwire may be removed. 
       FIG. 8  illustrates a slightly different bracket, which is shown in a section view similar to the section view of  FIG. 7 . In the embodiment of  FIG. 8 , all aspects of the bracket are substantially identical to the bracket of  FIG. 7  with the exception of the position and orientation of an occlusal-gingival opening  154 . In  FIG. 8 , the opening  154  is angled relative to the gingival-occlusal axis at an angle of about forty-five degrees. As with the previous embodiment, the clip  18  in  FIG. 18  is highly resilient, and its resiliency will hold the clip in either of its open position (solid lines in  FIG. 8 ) or closed position (broken lines in  FIG. 8 ). 
     In addition to the constructions shown in  FIGS. 1-8 , the bracket  14  may be formed as a lingual bracket in which case the attachment portion  58  would attach the bracket  14  to the lingual side of the tooth and all references to labial and lingual would be reversed. 
     Thus, the invention provides, among other things, a self-ligating orthodontic bracket assembly. Various features and advantages of the invention are set forth in the following claims.