Patent Document

CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 12/724,159, filed Mar. 15, 2010, and claims the benefit of U.S. Provisional Patent Application Ser. No. 61/160,653, filed Mar. 16, 2009. The entire disclosure of the prior application hereinabove is incorporated herein fully by reference. 
     
    
     RELATED FIELD OF THE INVENTION 
       [0002]    The present invention is related to orthodontic brackets, and in particular, to such brackets wherein one or more archwires can be secured in laterally entered archwire retaining channels. 
       SUMMARY OF THE INVENTION 
       [0003]    An orthodontic bracket is disclosed herein for retaining one or more archwires in position. The bracket includes a base having a tooth affixing side and an opposing side, and there is one or more archwire retention channels extending in the mesial-distal directions. Each of the archwire retention channels includes a pair of inverted archwire retaining regions on one side of the channel, wherein each of the retaining regions, in turn, includes a recess that opens generally towards an opposing side of the channel, the opposing side being, in one embodiment, part of the bracket base. Each such recess is for grasping or holding an archwire within the channel having the recess. A first of the archwire retention channels includes a first pair of gingivally located inverted archwire retaining regions whose recesses hold a common archwire. In an embodiment of the bracket having more than one archwire retention channel, a second of the archwire retention channels includes a second pair of occlusally located inverted archwire retaining regions whose recesses hold another archwire. Moreover, for each of the archwire retention channel(s), there is a corresponding archwire retaining ridge extending gingivally-occlusally along the opposing side bracket base between the two archwire retaining regions of the channel, wherein this retaining ridge contacts a portion of an archwire that faces away from the archwire portion being held in the recesses of the inverted archwire retaining regions for the channel. Accordingly, for each pair of archwire retaining regions and an archwire held by the pair, the corresponding archwire retaining ridge exerts a force on the archwire directed toward the interiors of the recesses of the inverted retaining regions of the pair. In particular, this force assists in seating the archwire in the retaining regions of the pair. 
         [0004]    In particular for the at least one of the archwire retention channel included in the bracket and an archwire provided therein, the elasticity of the archwire to retain an initial non-curved shape causes the archwire to resist a channel induced bow in the archwire (such bowing or curving shown in  FIG. 2B ). Thus, as an orthodontist positions the archwire in the at least one channel of the bracket, the corresponding retaining regions for the channel together with the corresponding retaining ridge, bind or wedge the archwire within the channel. Accordingly, the opposing forces between the channel and archwire secure the archwire within the channel. Thus, it is a feature of the bracket  20  that for each such archwire channel, there are channel archwire bowing portions that retain the archwire within the channel, wherein a spaced apart plurality of these bowing portions (e.g.,  40   a  and  40   b  for channel  28 ) contact the archwire at spaced apart locations on one side of the archwire&#39;s length, and wherein between such locations, there is at least one additional channel archwire bowing portion on an opposite side of archwire for inducing the archwire to press against the spaced apart plurality of contacting portions. Thus, the spaced apart plurality of bowing portions, and the at least one additional bowing portion induce oppositely directed forces on the archwire (such forces being traverse to the length of the archwire), and causing the archwire to bow or bend somewhat and to press against these bowing portions for holding the archwire within the channel. Said differently, the channel effectively is effectively bowed along its length. 
         [0005]    In some embodiments, one archwire retention channel may be configured to provide more than a single bow or bind of the archwire within the channel In particular, such a channel may be configured so that an archwire contained therein must form at least one “S” shape with the channel 
         [0006]    The novel bracket preferably has a generally square bracket base with opposing mesial-distal sidewalls, and opposing gingival-occlusal sidewalls that extend between the tooth affixing side and the opposing side (also referred to as an “upper side” herein),. Each of the above described retaining ridges is provided by a corresponding thickened portion of the bracket base that extends in the gingival-occlusal direction of the bracket approximately along a gingival-occlusal occlusal center line of the bracket base. The thickened portion gradually thins in the mesial-distal direction of the bracket, ending with the same thickness as the gingival-occlusal sidewalls. 
         [0007]    Two archwire retention bridges are also included on the novel bracket, wherein each end of each bridge includes one of the inverted archwire retaining regions from a different one of the first and second pairs identified above. A central archwire retention channel (positioned between the two archwire retention channels described above) extends in the mesial and distal direction along a central portion of the bracket. This channel is formed by the two archwire retention bridges which enclose spaced apart portions of the archwire retention channel for securing an archwire therein. 
         [0008]    Embodiments of the bracket may be made of stainless steel for strength or other materials, including ceramics, plastics, polycrystalline alumina material, alumina (aluminum oxide), and zirconia. The bracket base design allows for the bracket to be used in both direct and indirect bonding to patients&#39; teeth. Embodiments of the bracket may be formed via an injection molding technique. 
         [0009]    Such a universal bracket design may be primarily attached to the lingual side of patients&#39; teeth, but for embodiments of the bracket attached the labial/buccal side of a patients&#39; teeth, the bracket base tooth facing curvature may be specific to particular tooth types. 
         [0010]    This Summary section is neither intended nor should be construed as being representative of the full extent and scope of the present invention. Various embodiments of the present disclosure are set forth in the attached figures and in the detailed description hereinbelow and as embodied by the claims. Accordingly, this Summary does not contain all of the aspects and embodiments of the present disclosure, and is not meant to be limiting or restrictive in any manner. Furthermore, the disclosure should be understood by those of ordinary skill in the art to encompass obvious improvements and modifications thereto. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]      FIGS. 1-8  illustrate various views and embodiments of novel brackets according to the present disclosure. The drawings are not necessarily drawn to scale. 
           [0012]      FIG. 1  is a perspective view of a bracket  20  illustrating novel features for an orthodontic bracket. 
           [0013]      FIG. 2A  is a gingival view of the bracket  20  of  FIG. 1 , wherein the retaining ridge  25  and the archwire retention channel  28  are shown. 
           [0014]      FIG. 2B  is a gingival view of the bracket of  FIG. 1  with an archwire  68  passing through archwire retention channel  28  (as shown in  FIG. 2A ), wherein the archwire is held in place in the retaining regions  40   a,b  by, e.g., the retaining ridge  25 . 
           [0015]      FIGS. 3A and 3B  are side views of the bracket  20  of  FIG. 1  looking through the archwire retention channels  28 ,  32  and  36 . 
           [0016]      FIG. 4  is a top view of the bracket  20  of  FIG. 1 . 
           [0017]      FIG. 5  is lateral perspective view of the bracket  20  of  FIG. 1  with archwires  68  and  64  located in the gingival  28  and occlusal  36  archwire retention channels to provide, e.g., torque to a tooth  76  to which the bracket may be attached. 
           [0018]      FIG. 6  is a top view of the bracket  20  of  FIG. 1  with archwires  68  and  64  located in the gingival  28  and occlusal  36  archwire retention channels to provide tip to the tooth  80  to which the bracket is attached as one skilled in the art will understand. 
           [0019]      FIG. 7  is an end perspective view of the bracket  20  of  FIG. 1  with archwires  68  and  64  located in the gingival  28  (not shown) and occlusal  36  archwire retention channels to provide rotation to the tooth  84  to which the bracket is attached as one skilled in the art will understand. 
           [0020]      FIGS. 8A and 8B  show an embodiment of the novel bracket  20  with different archwire configurations attached thereto. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    Referring to  FIGS. 1-8 , various embodiments of a bracket  20  are shown, wherein the bracket includes:
       (a) A generally square bracket base  24  having an upper side  29 , a tooth affixing side  26 , opposing mesial-distal sidewalls  27 , and opposing gingival-occlusal sidewalls  30  as shown in  FIGS. 1 ,  2 A and  2 B. Additionally, the bracket base  24  has a pair of retaining ridges  25  extending from each of the opposing gingival-occlusal sidewalls  30  toward the interior of the upper side  29 .  FIGS. 1 and 2A  show one of retaining ridges  25 ;  FIG. 3A  shows both retaining ridges. Each of the retaining ridges  25  is provided by a corresponding thickened portion  23  ( FIGS. 1 ,  2 A and  2 B) of the bracket base  24  that extends in the gingival-occlusal direction of the bracket  20  approximately along a gingival-occlusal center line of the bracket base  24  (e.g., along the line L of  FIG. 4 ). The thickened portion  23  gradually thins in the mesial-distal direction of the bracket  20 , ending with the same thickness as the sidewalls  27 .   (b) A pair of inverted archwire retaining regions  40   a  and  40   b  on the gingival side of the bracket  20  ( FIGS. 1 and 2A ), and another pair of inverted archwire retaining regions  44   a  and  44   b  ( FIG. 1 ) on the occlusal side of the bracket. Each of the pairs ( 40   a,b  and  44   a,b ) is for retaining a respective archwire (e.g., archwire  68 ,  FIG. 2B ) therein. In particular, each of the inverted archwire retaining regions  40   a  and  40   b  provide a recess  37  ( FIGS. 1 and 2A ) for grasping or holding an archwire provided therein. Also, each of the inverted archwire retaining regions is attached to (and generally integral with) a corresponding support  39  ( FIG. 2A ) that connects the retaining region with the bracket base  24 . Each support  39  extends outwardly from the upper side  29  by a distance somewhat larger than the cross section of largest archwire to be retained in the recesses  37 . Moreover, each of the recesses  37  has an edge  43  (FIGS.  2 A,B and  3 B) that is spaced apart from the support  39  for the recess, wherein the distance between the edge and the support is also somewhat larger than the cross section of largest archwire to be retained in the recesses  37 .       
 
         [0024]    Note that for each of the pairs of the inverted archwire retaining regions  40   a,b  and  44   a,b , a corresponding one of the retaining ridges  25  ( FIGS. 1 ,  2 A,  2 B and  3 A) assists in securing an archwire (e.g., archwire  68 ) in the two recesses  37  of the pair. Accordingly, for each of the pairs  40   a,b  and  44   a,b , the recesses  37  for the pair operatively cooperate with a corresponding one of the retaining ridges  25  to provide a corresponding archwire retention channel, i.e., for an archwire retention channel  28 , the pair  40   a,b , defines one side of the channel  28  (i.e., an “outer” side) and the corresponding retaining ridge  25  provides the opposing side of the channel  28  (i.e., an “inner” side), and for an archwire retention channel  36 , the pair  44   a,b , defines one side of the channel  36  (i.e., an “outer” side) and the corresponding retaining ridge  25  provides the opposing side of the channel  36  (i.e., an “inner” side). Thus, when an archwire is received (and held) in the inverted archwire retaining regions  40   a,b  or  44   a,b  (i.e., archwire retention channel  28  or  36 ), this archwire is operatively coupled together with the bracket attached to a patient&#39;s tooth.
       (c) Two archwire retention bridges  56  and  60  ( FIGS. 1 ,  2 A,  2 B,  4 ,  5 A,  6  and  7 ), wherein each end of each bridge attaches to one of the inverted archwire retaining regions and/or the support  39  therefor. For example, i.e., the ends of the bridge  56  may be attached to the inverted archwire retaining regions  40   a  and  44   a  (or attached to the support  39  therefor), and the ends of the bridge  60  may be attached to the inverted archwire retaining regions  40   b  and  44   b  (or attached to the support  39  therefor).   (d) An archwire retention channel  32  ( FIGS. 1 ,  3 A, and  5 A) extending in the mesial and distal direction along a central portion of the bracket  20 . The two archwire retention bridges  56  and  60  (together with their corresponding inverted archwire retaining regions) enclose, and substantially define, spaced apart portions of the archwire retention channel  32  for securing an archwire therein ( FIG. 8B ).       
 
         [0027]    The bracket base  24  may be made of a variety of materials, but in one embodiment may be stainless steel for strength. However, other materials may be used including ceramics and plastics. The remainder of the bracket  20  may be composed of various materials in addition to those recited above (e.g., polycrystalline alumina material, alumina (aluminum oxide), zirconia). In one embodiment, the bracket  20  may be formed via an injection molding technique. 
         [0028]    The bracket base  24  may be a universal bracket design in that it can be attached to the surface of various tooth types (e.g., incisor, bicuspid, molar, etc). Moreover, such a universal bracket design does not require bracket identification to aid in identifying placement of the bracket and/or identifying a particular embodiment of the bracket  20 . Such a universal bracket design also leads to simplified inventory management since only one embodiment of the bracket  20  may be needed for placement on all teeth types instead of different embodiments of the bracket for different teeth types. However, such universal bracket design may be primarily for the lingual side of patients&#39; teeth. For embodiments of the bracket  20  to be provided on the labial/buccal side of patients&#39; teeth, the curvature of the tooth affixing side  26  may be specific to particular tooth types as one skilled in the art will understand. Accordingly, it is also within the scope of the present disclosure that markings or identifications may be provided on embodiments of the bracket  20  for identifying the bracket (e.g., as a universal bracket, or specific to a particular tooth type(s)), for identifying the manufacturer or distributor of the bracket, and/or for identifying a particular placement or orientation of the bracket on a tooth or tooth type. Note that descriptions of providing such markings and/or identifications are disclosed in U.S. Patent Application Publication 2008/0020338 filed Jul. 24, 2007 and published Jan. 24, 2008, this application being fully incorporated herein by reference. 
         [0029]    The bracket base  24  design allows for the bracket  20  to be used in both direct and indirect bonding. Note that the term direct bonding refers to applying adhesive directly to a patient&#39;s tooth and subsequently attaching a bracket  20  thereto. Indirect bonding refers to positioning one or more brackets  20  on a dental cast of a patient&#39;s teeth. The dental cast, having the brackets  20  attached thereto, is then surrounded with a material, wherein the material, once solidified, secures the brackets therein and can act as a transportation device for the brackets once the dental cast is dissolved away. Adhesive is then applied to the back of each of the brackets  20  prior to placing the transportation device containing the brackets onto the patient&#39;s teeth. Accordingly, in the indirect bonding technique, all of the brackets  20  are bonded to the patient&#39;s teeth simultaneously. Once the brackets  20  are bonded, the transportation device is removed from the teeth, leaving behind the brackets attached to the teeth. 
         [0030]    Regarding the retaining ridges  25  described above, each such ridge corresponds to a maximal offset from the tooth affixing side  26  along a corresponding one of the archwire retention channels  28  and  36 . Moreover, in at least some embodiments, such a ridge  25  has its maximal offset centered on line L of  FIG. 4 . In the embodiment of the bracket  20  shown in  FIGS. 2A and 2B , the contour of each of the retaining ridges  25  is a smooth arc without undulations in the mesial-distal direction, and may also be a smooth arc in the gingival-occlusal direction without undulations. However, it is within the scope of the present disclosure that in the gingival-occlusal direction, such a ridge  25  may reach its maximal offset at any point where the ridge transverses its corresponding archwire retention channel ( 28  or  36 ) as long as the ridge effectively assists in wedging or holding an archwire in the channel (i.e., the recesses  37  of the channel). Thus, the thickened portion  23  ( FIG. 1 ) for each retaining ridge  25  may induce a force upon an archwire  68  or  64  (e.g.,  FIG. 5A ) to retain it in the archwire retaining regions of the corresponding archwire retention channel  28  or  36 . Note that each of the two retaining ridges  25  may have symmetrical profiles (i.e., minor images of one another about the center line L of  FIG. 4 , and about mesial-distal center line through the bracket). Moreover, note that the maximal offset for a retaining ridge  25  may occur just outside its corresponding archwire retention channel, e.g., on the mesial-distal perimeter of the channel furthest from the central retention channel  32 . Such placements of the maximal offsets may not only provide forces for securing an archwire within the corresponding recesses  37 , but also apply a force on the archwire for inhibiting the archwire from moving in a direction generally lateral to the upper side  29 . 
         [0031]    In another embodiment of the bracket  20 , the retaining ridges  25  may have a larger or smaller maximal offset from the tooth affixing side  26  to the upper side  29  of the bracket base  24  when compared to the embodiments of the figures. Moreover, one of the retaining ridges  25  may have a larger maximal offset from the tooth affixing side  26  than the other retaining ridge  25 . This variance in the maximal offset of the retaining ridges  25  may allow for and aid in the retention of different diameter archwires in the retaining regions  40   a,b  and  44   a,b.    
         [0032]    In another embodiment of the bracket  20 , one or more of the retaining ridges  25  may have a corresponding secondary retaining ridge located at the gingival or occlusal edges of the bracket base  24 . These secondary retaining ridges may be located on the upper side  29  at the gingival and/or occlusal edges of the bracket base  24 . Such secondary retaining ridges may extend in the mesial-distal direction on the upper side  29  of the bracket base  24 . The secondary retaining ridges may have varying shapes (e.g., hemispherical or elliptical). Accordingly, the retaining regions  40   a,b  and  44   a,b , in conjunction with the secondary retaining ridges, keep the corresponding archwire secured in one of the corresponding archwire retention channels  28  and  36  (more specifically their recesses  27 ). 
         [0033]    For further description of the archwire retention channels  28 ,  32  and  36 , reference is made to  FIG. 3A  which provides a lateral (side) view of the bracket  20  along a gingival-occlusal side. The center archwire retention channel  32  of the bracket  20  is enclosed by the two spaced apart portions of the archwire retention bridges  56  and  60  (FIGS.  1 , 2 A,  2 B,  4 ,  5 A,  6  and  7 ), and the upper side  29  of the bracket base  24 . As described above, each of the gingival archwire retention channel  28  and the occlusal archwire retention channel  36  is provided by: (i) partially enclosed spaced apart recesses  27  of a pair of inverted archwire retaining regions, respectively,  40   a,b  or  44   a,b , and (ii) the upper side  29  of the bracket base  24 . Both the gingival archwire retention channel  28  and the occlusal archwire retention channel  36  may be mirror images of one another. Each of the inverted archwire retaining regions  40   a,b  for the gingival archwire retention channel  28 , and each of the retaining regions  44   a,b  for the occlusal archwire retention channel  36  may be generally circular in profile (as shown in, e.g.,  FIG. 3A ). Each such profile may generally match the curvature of, e.g., the cross section of a corresponding archwire to be provided therein. In  FIG. 3A , a dashed circular cross section  38  of such an archwire is shown in the archwire retaining regions  44   a,b  of the occlusal archwire retention channel  36 . The diameter  39  of the archwire retention channel  36  may be sufficiently surrounded by the inverted archwire retaining regions  44   a,b  to grip and retain the archwire therein. In at least one embodiment, the opening  42  for receiving the archwire into the channel  36  is preferably approximately the same size as the diameter of the archwire cross section  38  along the axis  37 , e.g., smaller or larger by approximately 0.01 to 0.02 inches. As also illustrated in  FIG. 3A , each of the inverted archwire retaining regions  44   a,b  may surround somewhat more than 180 degrees of the circular cross section of an archwire positioned in the occlusal archwire retention channel  36 . Note that a similar description can also be provided for the gingival archwire retention channel  28  in that the channel  28  may be a mirror image of occlusal archwire retention channel  36 . However, it is within the scope of the present disclosure that the gingival archwire retention channel  28  may be configured differently from the occlusal archwire retention channel  36 , e.g., the gingival archwire retention channel  28  may secure different sizes of archwires therein from the archwires for the occlusal archwire retention channel  36 . Also, either or both of the archwire retention channels  28  and  36  may have an elliptical profile or other profile instead of the circular profile shown in  FIG. 3A . Further, an embodiment of the bracket  20  may have only one of the archwire retention channels  28  or  36 . 
         [0034]    Referring to  FIG. 3B , an embodiment of the bracket  20 A is shown that includes a retaining region (e.g.,  44   a ) that is shaped or configured to retain archwires having substantially different cross sectional diameters. An archwire having a diameter  39  ( FIG. 3A ) may be snapped into the retaining region  44   a  as indicated in  FIG. 3A . However, an archwire having a much smaller cross section  41 , as shown in  FIG. 3B , may also be provided in the channel  36 . In particular, the smaller diameter archwire may snap into (or is otherwise retained) in an upper section  57  of the retaining region. Note that in one embodiment, a bead (not shown) may be strung on this smaller diameter archwire such that the bead is positioned between the retaining regions  44   a  and  44   b  so that the bead contacts the corresponding retaining ridge  25  for the occlusal archwire retention channel  36  in a manner that assists in locking the archwire into the upper section  57 . 
         [0035]    Whether the bracket embodiment of  FIG. 3A  or  3 B is provided, multiple sizes of archwires may be utilized in each of the archwire retention channels  28 ,  32  and  36 . The range in the maximal cross sectional extent of the archwires that may be utilized can be from 0.008 inches to 0.024 inches, and such cross sections may be generally circular in cross sectional shape but different cross sectional shapes may be used, e.g., at least rectangular or square cross sectional shapes for the central archwire retention channel  32 . The multiple sizes of archwires may provide varying forces and friction levels ranging from an alignment force having a low friction, to a leveling force having a moderate friction, to a finishing force having a maximum friction as one skilled in the art will understand. In particular, the inverted archwire retaining regions  40   a,b  and  44   a,b  allow for the archwires  68  or  64  ( FIGS. 5A ,  6  and  7 ) to be attached to the bracket  20  without the use of ligatures. 
         [0036]    In another embodiment, the archwire retaining regions  40   a  and  44   a  (or  40   b  and  44   b ) may be joined together, above the upper side  29 . Such joining of the retaining regions for one of the archwire retention channels  28  or  26  may form a single integral retaining region, or the joining may be in form of a bridge therebetween similar to the bridges  56  and  60  (except extending in the mesial-distal direction rather than the gingival-occlusal direction). Regardless, there may be a cutout (not shown) over the corresponding retaining ridge  25  so that when the archwire contacts the retaining ridge  25 , the archwire is wedged into this cutout. In another embodiment, there may be only one of the outer archwire retention channels  28  and  36  utilized to retain an archwire. 
         [0037]    Referring to  FIG. 4 , a top view of the bracket  20  is shown wherein the center archwire retention channel  32  on the bracket is defined by the spaced apart portions of the archwire retention bridges  56  and  60  and the upper side  29  of the bracket base  24 . The archwire retention bridges  56  and  60  connect and reinforce the inverted archwire retaining regions  40   a  to  44   a  and  40   b  to  44   b.  The smooth rounded contours and edges  65  of the inverted archwire retaining regions  40   a,b  and  44   a,b  provide for patient comfort, particularly when such brackets are placed on the lingual side of a patient&#39;s teeth. In the center archwire retention channel  32 , the archwire is enclosed on all sides ( FIGS. 3A and 3B ) at two points along the channel, i.e., using the archwire retention bridges  56  and  60  ( FIG. 4 ). 
         [0038]    A lateral view of the bracket  20 , as shown in  FIG. 5 , shows an archwire  64  in the occlusal archwire retention channel  36  and an archwire  68  in the gingival archwire retention channel  28 . The occlusal  64  and gingival  68  archwires are held place via the friction system created by the inverted archwire retaining regions  40   a,b  and  44   a,b  in combination with the ridges  25  (not shown in  FIG. 5 ).  FIG. 5  also shows where the bracket  20  may reside on a tooth when it is bonded thereto. The arrows  77  and  78  ( FIG. 5 ) indicate the forces for a torque that the bonded bracket  20  may apply to the tooth. 
         [0039]      FIG. 6  provides a top view of the bracket  20  bonded to a tooth  80  wherein there is an archwire  64  in the occlusal archwire retention channel  36 , and an archwire  68  in the gingival archwire retention channel  28 . The arrows  90  and  91  indicate the motion of tip (angulation) that the bracket  20  may apply to the tooth once it is bonded and the archwires are configured appropriately. 
         [0040]    An end perspective view of the bracket  20  is shown in  FIG. 7  with an archwire  64  in the occlusal archwire retention channel  36  and an archwire  68  in the gingival archwire retention channel  28 . This figure also shows the bracket bonded to a tooth  84  thereby showing where the bracket  20  may reside on the tooth when it is bonded thereto. The arrows  93  and  94  indicate the motion of rotation that the bracket  20  and the archwires  64  and  68  may apply to the tooth. 
         [0041]    A plurality of the brackets  20  is shown connected together by archwires in  FIGS. 8A and 8B .  FIG. 8A  shows the plurality of brackets  20  connected together by an archwire  88  extending through the corresponding occlusal archwire retention channels  36  of the brackets.  FIG. 8A  also shows a second archwire  92  secured in the center archwire retention channel  32  of the brackets  20 , providing dynamic sectional control in the movement of the teeth, as one skilled in the art will understand.  FIG. 8B  displays how another configuration, wherein there is an archwire  96  in the occlusal archwire retention channel  36  of the brackets  20 . The archwire  96  is also configured so that its end is secured in the center archwire retention channel  32  of the rightmost one of the brackets  20 , thereby creating a loop like shape. It is worth noting that due to the diminutive size of the brackets  20  relative to the teeth to which they are attached (as shown in  FIGS. 8A and 8B ), the size of these brackets  20  may allow for the bonding of two such brackets  20  on a single tooth. For example,  FIG. 8B  shows two such brackets  20  affixed to a molar. 
         [0042]    Alternative embodiments of the bracket  20  include providing the inverted archwire retaining portions so that instead of their recesses  37  opening toward the base  24 , such recesses open in another direction (e.g., away from the base, or generally parallel with the upper side  29  of the base). In such embodiments, the retaining ridge  25  is also repositioned to face in the direction toward such recesses for retaining an archwire in the same manner as, e.g., shown in  FIG. 2B  except that the base  24  in this figure would no longer be the base of the bracket. Instead, the base would attach, e.g., to the top of the retaining portions  40   a,b  and  44   a,b , or alternatively attach the bracket components shown  FIG. 2B  to a (new) bracket base that is oriented substantially perpendicular to the base shown in  FIG. 2B . 
         [0043]    In each of the embodiments of the bracket  20  disclosed hereinabove, at least one of the archwire retention channels  28  and  36  is provided, wherein for an archwire provided therein, the elasticity of the archwire to retain an initial non-curved shape causes the archwire to resist the channel induced bow in the archwire (such curving shown in  FIG. 2B ). Thus, as an orthodontist positions the archwire in the at least one channel of the bracket  20 , the corresponding retaining regions ( 40  and  44 ) for the channel together with the corresponding retaining ridge  25  bind or wedge the archwire within the at least one channel. Accordingly, the opposing forces between the channel and archwire are believed to secure the archwire within the channel. Thus, it is a feature of the bracket  20  that for each such archwire channel (e.g.,  28  and/or  36 ), there are channel archwire bowing portions that retain the archwire within the channel, wherein a spaced apart plurality of these bowing portions (e.g.,  40   a  and  40   b  for channel  28 ) contact the archwire at spaced apart locations on one side of the archwire&#39;s length, and wherein between such locations, there is at least one additional channel archwire bowing portion on an opposite side of archwire for inducing the archwire to press against the spaced apart plurality of contacting portions. Thus, the spaced apart plurality of bowing portions, and the at least one additional bowing portion induce oppositely directed forces on the archwire (such forces being traverse to the length of the archwire), and causing the archwire to bow or bend somewhat and to press against these bowing portions for holding the archwire within the channel. 
         [0044]    In use, after an orthodontist has secured the bracket  20  to one of a patient&#39;s teeth, the orthodontist may exert a force (e.g., substantially parallel to the upper side  29 ) on a corresponding archwire to force the archwire enter one or both of the archwire retention channels ( 28  or  36 ), wherein such force induces the corresponding archwire to bow in the channel Alternatively, the orthodontist may thread the archwire into such a channel, wherein the orthodontist pushes the archwire into the channel by purposely bowing or binding the archwire to follow the bow of the channel, and then once the archwire is threaded through the channel, the orthodontist can then bend the archwire into the correct orientation to attach the archwire to, e.g., a next orthodontic appliance attached to, e.g., a next tooth. Note, that such subsequent bending of the archwire by the orthodontist is believed to also provide similar forces on the archwire (and traverse to the length thereof) as described above for securing the archwire within the channel. 
         [0045]    The disclosure herein describes the best mode known to carry out the invention as claimed in the claims hereinbelow. Moreover, the foregoing disclosure has been provided for purposes of illustration and description. This disclosure is not intended to limit the invention claimed hereinbelow, and various embodiments thereof. Variations, embodiments and modifications will be apparent to those skilled in the art and are intended to be within the scope of the following claims.

Technology Category: 1