US20020132206A1 - Orthodontic bracket - Google Patents

Abstract

In one embodiment, a pre-engaging orthodontic bracket includes a body having a lingual surface for attachment to a tooth, a pair of laterally spaced gingival tie wings and a pair of laterally spaced occlusal tie wings. The gingival and occlusal tie wings project from a labial surface of the body. An archwire slot extends mesiodistally across the body and between the gingival and occlusal tie wings at opposed mesial and distal sides of the body to accommodate an archwire. A pivot pin extends between a pair of the tie wings at opposed mesial and distal sides of the body. A shutter is moveable relative to the body between an open position in which placement and removal of an archwire into the archwire slot is facilitated and a closed position in which placement and removal of an archwire into the archwire slot is inhibited.

Description

RELATED APPLICATIONS
• The present application is a continuation-in-part of U.S. application Ser. No. 08/625,944, filed on Apr. 1, 1996 which is a continuation-in-part of U.S. application Ser. No. 08/412,338 filed on Mar. 31, 1995 now abandoned which is a continuation-in-part of U.S. application Ser. No. 08/206,724 filed on Mar. 7, 1994 now issued and granted under U.S. Pat. No. 5,474,445.[0001]
FIELD OF THE INVENTION
• The present invention relates in general to pre-engaging orthodontic brackets and in particular to a pre-engaging twin orthodontic bracket and to a plurality of orthodontic brackets forming a set of braces.[0002]
BACKGROUND OF THE INVENTION
• According to established orthodontic techniques, it is well known that one is able to ligate an archwire to a bracket utilizing an elastic, elastomeric or metal ligature. In a twin edgewise orthodontic bracket, the elastic ligature is stretched around respective undercuts of gingival and occlusal tie wings so as to overlay the archwire at mesial and distal ends of the bracket.[0003]
• The ligating procedure involves carefully stretching the elastic or elastomeric ligature (or wrapping and twisting a metal ligature) around the tie wings utilizing appropriate orthodontic instruments. It has been found that the time-consuming ligation procedure contributes to lengthy chair time. Furthermore, the elastic ligatures are known to lose their elasticity with time and are subject to degradation. Also, the elastic and metal ligatures have been known to trap food particles in areas of the bracket which are difficult for the patient to clean, and to increase the level of friction against the archwire. Finally, the use of sharp metal ligatures around the bracket can subject the clinician to unnecessary exposure to infectious bacteria, or viruses such as hepatitis B, or possibly the HIV virus particularly in blood.[0004]
• In an effort to overcome these disadvantages of elastic ligatures, certain advances have been made in the area of pre-engaging orthodontic brackets. Each of U.S. Pat. Nos. 4,144,642; 4,248,588; 4,698,017; 3,772,787; 4,786,242; 4,559,012; 4,561,844; 4,655,708; 4,077,126; 4,419,078; 4,634,661; 4,197,642; and 4,712,999 illustrate one or more designs of pre-engaging brackets. These prior art devices overcome some of the disadvantages associated with elastic ligatures. For example, pre-engaging orthodontic brackets eliminate, or at least reduce, exposure of the clinician to sharp ligatures, thereby alleviating the problem of contracting harmful bacteria or viruses. In addition, pre-engaging orthodontic brackets permit continuous low deflection differential archwire contact separately for both round and rectangular archwires at at least two different levels of contact, which is not possible with degrading elastic, elastomeric or rigid, high deflection metal ligatures. However, most of the known prior art pre-engaging orthodontic brackets lack the reliability and the accessible ease of operability that most clinicians require. In addition, the majority of prior art pre-engaging orthodontic brackets are of a single design that have three or fewer tie wings.[0005]
• It is therefore an object of the present invention to provide a novel twin pre-engaging orthodontic bracket which obviates or mitigates at least one of the above-identified disadvantages associated with prior art orthodontic brackets.[0006]
SUMMARY OF THE INVENTION
• According to one aspect of the present invention there is provided a pre-engaging orthodontic bracket for attaching an archwire to a tooth comprising:[0007]
• a body having a lingual surface for attachment to a tooth, a pair of laterally spaced gingival tie wings and a pair of laterally spaced occlusal tie wings, said gingival and occlusal tie wings projecting from a labial surface of said body, both said gingival tie wings and occlusal tie wings at opposed mesial and distal sides of said body being separated by an interwing region of said body;[0008]
• an archwire slot extending mesiodistally across said body and between the gingival and occlusal tie wings at opposed mesial and distal sides of said body to accommodate an archwire, said archwire slot being interrupted by said interwing region;[0009]
• a locking shutter moveable relative to said body between an open position in which placement and removal of said archwire in said archwire slot is facilitated and a closed position in which placement and removal of said archwire in said archwire slot is inhibited; and[0010]
• biasing means carried by said locking shutter and engageable with an archwire in said archwire slot when said locking shutter is in said closed position, said biasing means resiliently urging said archwire into said archwire slot to provide a continuous corrective force thereon.[0011]
• In one embodiment, the biasing means is in the form of a leaf spring secured to the locking shutter. The leaf spring can extend mesiodistally or occlusiogingivally. In another embodiment, the locking shutter is formed of resilient material and biases the archwire when the locking shutter is in the closed position thereby to constitute the biasing means.[0012]
• According to another aspect of the present invention there is provided a pre-engaging orthodontic bracket for attaching an archwire to a tooth comprising:[0013]
• a body having a lingual surface for attachment to a tooth, a pair of laterally spaced gingival tie wings and a pair of laterally spaced occlusal tie wings, said gingival and occlusal tie wings projecting from a labial surface of said body, both said gingival tie wings and occlusal tie wings at opposed mesial and distal sides of said body being separated by an interwing region of said body;[0014]
• an archwire slot extending mesiodistally across said body and between the gingival and occlusal tie wings at opposed mesial and distal sides of said body to accommodate an archwire, said archwire slot being interrupted by said interwing region;[0015]
• a locking shutter movable relative to said body between an open position in which placement and removal of said archwire in said archwire slot is facilitated and a closed position in which placement and removal of said archwire from said archwire slot is inhibited; and[0016]
• biasing means engageable with an archwire in said archwire slot when said locking shutter is in said closed position to urge said archwire toward said locking shutter to provide a continuous corrective force thereon.[0017]
• In one embodiment, the biasing means is in the form of a resilient spring member extending mesiodistally along the archwire slot and secured to the body. The spring member has at least one free end and can be dimensioned to engage an archwire either within the archwire slot or exterior to the archwire slot. In another embodiment, the resilient spring member extends occlusiodistally across the archwire slot in the interwing region and is secured to the body adjacent one end thereof.[0018]
• In another embodiment, the biasing means is in the form of magnetized elements within the body adjacent the archwire slot to present a repelling magnetic force to the archwire to bias the archwire towards the locking shutter. In yet another embodiment, the biasing means is in the form of a pair of spring-loaded pistons accommodated by the body adjacent opposed mesial and distal ends of the archwire slot to urge the archwire towards the locking shutter.[0019]
• According to still yet another aspect of the present invention there is provided a pre-engaging orthodontic bracket for attaching an archwire to a tooth comprising:[0020]
• a body having a lingual surface for attachment to a tooth, a pair of laterally spaced gingival tie wings and a pair of laterally spaced occlusal tie wings, said gingival and occlusal tie wings projecting from a labial surface of said body, both said gingival tie wings and occlusal tie wings at opposed mesial and distal sides of said body being separated by an interwing region of said body;[0021]
• an archwire slot extending mesiodistally across said body and between the gingival and occlusal tie wings at opposed mesial and distal sides of said body to accommodate an archwire, said archwire slot being interrupted by said interwing region; and[0022]
• a locking shutter pivotal about at least one pivot pin between an open position in which placement and removal of said archwire in said archwire slot is facilitated and a closed position in which placement of said archwire in said archwire slot is inhibited.[0023]
• In one embodiment, the orthodontic bracket includes one pivot pin extending between the tie wings of one of the two pairs and wherein the locking shutter includes a single loop at one end thereof to surround the pivot pin. In another embodiment, the orthodontic bracket includes a pair of pivot pins, each accommodated by each tie wing of one of the two pairs. In this case, the locking shutter includes a pair of laterally spaced single loops surrounding the pivot pins.[0024]
• Preferably, the locking shutter includes a marker thereon to identify generally the center of the archwire slot when the locking shutter is in the closed position. It is also preferred that the orthodontic bracket further includes a lubricating or sealing agent carried by one or more of the body, archwire slot, locking shutter and archwire.[0025]
• According to still yet another aspect of the present invention there is provided a body for an orthodontic bracket having a mesiodistally extending archwire slot formed therein and gingival and occlusal surfaces shaped to deflect food debris and plaque mesially and distally therefrom when secured to a tooth.[0026]
• According to still yet another aspect of the present invention there is provided a set of braces including a plurality of orthodontic brackets to be attached to an individual's teeth, said braces including self-engaging twin orthodontic brackets to be attached to the central and lateral teeth and first and second molars of said individual and single orthodontic brackets to be attached to the cuspid and premolar teeth of said individual.[0027]
• The present invention provides advantages in that the orthodontic brackets provide predictability and accurate control of tooth movement while enhancing treatment progress. The orthodontic brackets are aesthetically pleasing due to their symmetrical designs and provide for easier hygiene than prior art orthodontic brackets.[0028]
BRIEF DESCRIPTION OF THE DRAWINGS
• Preferred embodiments of the present invention will now be described more fully with reference to the accompanying drawings, in which:[0029]
• FIG. 1 is a perspective view of a pre-engaging twin orthodontic bracket in accordance with the present invention;[0030]
• FIG. 2[0031]ais a side elevational view of the orthodontic bracket of FIG. 1;
• FIG. 2[0032]bis a side elevational view of the orthodontic bracket of FIG. 1 in an open position;
• FIGS. 3[0033]aand3bare occlusal views of an incisor section to which the orthodontic bracket of FIG. 1 of the present invention is attached, showing low deflection moment during movement of the tooth;
• FIG. 4 is a front elevational view of an orthodontic bracket of the type shown in FIG. 1 positioned on a tooth;[0034]
• FIG. 5 is a perspective view of an alternative embodiment of a pre-engaging twin orthodontic bracket in accordance with the present invention;[0035]
• FIG. 6 is a front elevational view of yet another alternative embodiment of a pre-engaging twin orthodontic bracket in accordance with the present invention;[0036]
• FIG. 7 is a cross-sectional view of FIG. 6 taken along line[0037]7-7;
• FIG. 8 is a three-quarter perspective view of the orthodontic bracket of FIG. 6;[0038]
• FIGS. 9[0039]aand9bare cross-sectional views of FIG. 8 taken along line9-9 with the shutter in closed and open positions respectively;
• FIG. 10 is an enlarged cross-sectional view of a portion of the orthodontic bracket of FIG. 8 with the pivot pin omitted;[0040]
• FIGS. 11[0041]aand11bare perspective and front elevational views respectively of a shutter forming part of the orthodontic bracket of FIG. 6.
• FIG. 12 is a front elevational view of an alternative embodiment of an orthodontic bracket in accordance with the present invention having a sliding shutter;[0042]
• FIG. 13 is a side elevational view of the orthodontic bracket of FIG. 12;[0043]
• FIG. 14 is a view similar to FIG. 12 of the orthodontic bracket showing movement of the shutter to an open position;[0044]
• FIG. 15 is a side elevational view of the orthodontic bracket of FIG. 14 with the shutter in the open position;[0045]
• FIG. 16[0046]ais a perspective view of another alternative embodiment of an orthodontic bracket in accordance with the present invention having a sliding shutter shown in an open position;
• FIG. 16[0047]bis a side elevational view of the orthodontic bracket shown in FIG. 16b;
• FIG. 17[0048]ais a perspective view of the orthodontic bracket of FIG. 16ashowing the shutter in a closed position;
• FIG. 17[0049]bis a side elevational view of the orthodontic bracket shown in FIG. 17a;
• FIG. 18 is a front elevational view of an alternative embodiment of an orthodontic bracket in accordance with the present invention;[0050]
• FIG. 19 is a side elevational view of the orthodontic bracket of FIG. 18;[0051]
• FIG. 20 is a top plan view of the orthodontic bracket of FIG. 18;[0052]
• FIG. 21 is a partially exploded three-quarter perspective view of a still yet another embodiment of an orthodontic bracket in accordance with the present invention;[0053]
• FIG. 22 is a three-quarter perspective view similar to FIG. 21 of the orthodontic bracket in a closed position;[0054]
• FIG. 23 is a side elevational view of the orthodontic bracket of FIG. 22 accommodating an archwire;[0055]
• FIG. 24 is a side elevational view of the orthodontic bracket of FIG. 22 in an open position;[0056]
• FIG. 25 is a front elevational view of a further embodiment of an orthodontic bracket in accordance with the present invention having a resiliently biased locking shutter;[0057]
• FIG. 26 is a side elevational view of the orthodontic bracket of FIG. 25 in an open position;[0058]
• FIG. 27 is a side elevational view of the orthodontic bracket of FIG. 25 in a closed position;[0059]
• FIG. 28 is an exploded three-quarter perspective view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention;[0060]
• FIG. 29 is a three-quarter perspective view of the orthodontic bracket of FIG. 28 in a closed position;[0061]
• FIG. 30[0062]ais a side elevational view of the orthodontic bracket of FIG. 29 in an open position;
• FIG. 30[0063]bis a side elevational view of the orthodontic bracket of FIG. 29 in a closed position;
• FIG. 31 is a three-quarter perspective view of the orthodontic bracket of FIG. 29 in the open position;[0064]
• FIG. 32 is a front elevational view of yet another embodiment of an orthodontic bracket in accordance with the present invention;[0065]
• FIG. 33 is a side elevational view of the orthodontic bracket of FIG. 32;[0066]
• FIG. 34 is an occlusal view of the orthodontic bracket of FIG. 32;[0067]
• FIG. 35 is a side elevational view of a shutter forming part of the orthodontic bracket of FIG. 32;[0068]
• FIG. 36 is a front elevational view of the shutter of FIG. 35;[0069]
• FIG. 37 is a three-quarter perspective view of still yet a further embodiment of an orthodontic bracket in accordance with the present invention;[0070]
• FIG. 38 is a front elevational view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention in a closed position;[0071]
• FIG. 39 is a front elevational view of the orthodontic bracket of FIG. 38 in an open position;[0072]
• FIG. 40 is a side elevational view of the orthodontic bracket of FIG. 38 accommodating a round archwire;[0073]
• FIG. 41 a is a cross-sectional view of an alternative embodiment of a pivot pin and shutter for use with the orthodontic bracket of FIG. 38;[0074]
• FIG. 41 is a side elevational view of the orthodontic bracket of FIG. 39 accommodating a round archwire;[0075]
• FIG. 42 is a front elevational view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention in a closed position;[0076]
• FIG. 43 is a front elevational view of the orthodontic bracket of FIG. 42 in an open position;[0077]
• FIG. 44 is a side elevational view of the orthodontic bracket of FIG. 42 accommodating a round archwire;[0078]
• FIG. 45 is a side elevational view of the orthodontic bracket of FIG. 43 accommodating a round archwire;[0079]
• FIG. 45[0080]ais a front elevational view of an alternative embodiment of a shutter for use with the orthodontic bracket of FIG. 42;
• FIG. 46 is a front elevational view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention in a closed position;[0081]
• FIG. 47 is a front elevational view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention in a closed position;[0082]
• FIG. 48 is an exploded three-quarter perspective view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention similar to that shown in FIGS.[0083]28 to31;
• FIG. 49 is a three-quarter perspective view of the orthodontic bracket of FIG. 48 in a closed position;[0084]
• FIG. 50 is a side elevational view of the orthodontic bracket of FIG. 49 in an open position;[0085]
• FIG. 51 is a side elevational view of the orthodontic bracket of FIG. 49 in a closed position;[0086]
• FIG. 52 is a three-quarter perspective view of the orthodontic bracket of FIG. 49 in the open position;[0087]
• FIG. 53 is a front elevational view of an alternative embodiment of an orthodontic bracket in accordance with the present invention having a sliding shutter similar to that shown in FIGS.[0088]12 to15;
• FIG. 54 is a side elevational view of the orthodontic bracket of FIG. 53;[0089]
• FIG. 55 is a side elevational view of the orthodontic bracket of FIG. 53 with the shutter in the open position;[0090]
• FIG. 56 is a front elevational view of a further embodiment of an orthodontic bracket in accordance with the present invention having a resiliently biased locking shutter similar to that shown in FIGS.[0091]25 to27;
• FIG. 57 is a side elevational view of the orthodontic bracket of FIG. 56 in an open position;[0092]
• FIG. 58 is a side elevational view of the orthodontic bracket of FIG. 56 in a closed position;[0093]
• FIG. 59 is a front elevational view of yet another embodiment of an orthodontic bracket in accordance with the present invention similar to that shown in FIGS.[0094]32 to36;
• FIG. 60[0095]ais a side elevational view of the orthodontic bracket of FIG. 59;
• FIG. 60[0096]bis a side elevational view of the orthodontic bracket of FIG. 59 in an open position;
• FIG. 61 is a side elevational view of a shutter forming part of the orthodontic bracket of FIG. 59;[0097]
• FIG. 62 is a front elevational view of the shutter of FIG. 61;[0098]
• FIG. 63 is a front elevational view of still a further embodiment of an orthodontic bracket in accordance with the present invention with the shutter removed;[0099]
• FIG. 64 is a side elevational view of the orthodontic bracket of FIG. 63 with the shutter installed;[0100]
• FIG. 65 is a front elevational view of the orthodontic bracket of FIG. 63 with the shutter installed;[0101]
• FIG. 66 is a top plan view of the orthodontic bracket of FIG. 65;[0102]
• FIG. 67 is a side elevational view of the orthodontic bracket of FIG. 63, similar to FIG. 64, with the shutter in an open position;[0103]
• FIG. 68 is a three-quarter perspective view of the orthodontic bracket of FIG. 63;[0104]
• FIG. 69 is a side elevational view of an alternative embodiment of a shutter for use with the orthodontic bracket of FIG. 63;[0105]
• FIG. 70 is a side elevational view of a further alternative embodiment of a shutter for use with the orthodontic bracket of FIG. 63;[0106]
• FIG. 71 is a rear elevational view of the shutter of FIG. 70;[0107]
• FIG. 72 is a side elevational view of a still further embodiment of a shutter for use with the orthodontic bracket of FIG. 63;[0108]
• FIG. 73 is a rear elevational view of the shutter of FIG. 72;[0109]
• FIG. 74 is a front elevational view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention;[0110]
• FIG. 75 is a side elevational view of the orthodontic bracket of FIG. 74 in a closed position;[0111]
• FIG. 76 is a side elevational view of the orthodontic bracket of FIG. 75 in an open position;[0112]
• FIG. 77 is a cross-sectional view of FIG. 76;[0113]
• FIG. 78 is a perspective view of a shutter used in the orthodontic bracket of FIG. 74;[0114]
• FIG. 79 is a front elevational view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention;[0115]
• FIG. 80 is a perspective view of the orthodontic bracket of FIG. 79;[0116]
• FIG. 81 is a side elevational view of the orthodontic bracket of FIG. 79;[0117]
• FIG. 82 is a side elevational view of the orthodontic bracket of FIG. 79 accommodating a larger archwire;[0118]
• FIG. 83 is a front elevational view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention;[0119]
• FIG. 84 is a side elevational view of the orthodontic bracket of FIG. 83 in a closed position and accommodating an archwire;[0120]
• FIG. 85 is a side elevational view of the orthodontic bracket of FIG. 83 showing the initial release of the shutter;[0121]
• FIG. 86 is a side elevational view of the orthodontic bracket of FIG. 83 showing further movement of the shutter;[0122]
• FIG. 87 is a side elevational view of the orthodontic bracket of FIG. 83 showing the shutter in a fully open position;[0123]
• FIG. 88 is a front elevational view of yet another alternative embodiment of an orthodontic bracket in accordance with the present invention;[0124]
• FIG. 89 is a perspective view of a component forming part of the orthodontic bracket of FIG. 88;[0125]
• FIG. 90 is a perspective view of an alternative embodiment of the component of FIG. 89;[0126]
• FIGS. 91[0127]aand91bare side elevational views of embodiments of an orthodontic tool;
• FIG. 92[0128]ais a front elevational view of another embodiment of an orthodontic bracket in accordance with the present invention;
• FIG. 92[0129]bis a side elevational view of the orthodontic bracket of FIG. 92a;
• FIG. 92[0130]cis a top plan view of the orthodontic bracket of FIG. 92a;
• FIG. 92[0131]dis another side elevational view of the orthodontic bracket of FIG. 92a;
• FIG. 93 is a perspective view of a portion of another embodiment of an orthodontic bracket in accordance the present invention;[0132]
• FIG. 94 is a front elevational view of yet another embodiment of an orthodontic bracket in accordance with the present invention;[0133]
• FIG. 95 is a side elevational view of still yet another alternative embodiment of an orthodontic bracket in accordance with the present invention;[0134]
• FIGS. 96[0135]aand96bare front elevational and cross-sectional views of another embodiment of an orthodontic bracket in accordance with the present invention;
• FIGS. 97[0136]ato97care front elevational, side elevational and top plan views of another embodiment of an orthodontic bracket in accordance with the present invention;
• FIGS. 98[0137]aand98bare front elevational and cross-sectional views of another embodiment of an orthodontic bracket in accordance with the present invention;
• FIGS. 98[0138]cand98dare front and side elevational views of another embodiment of an orthodontic bracket in accordance with the present invention;
• FIGS. 99[0139]aand99bare front and side elevational views of another embodiment of an orthodontic bracket in accordance with the present invention;
• FIGS. 100[0140]ato100care front elevational, side elevational and top plan views of another embodiment of an orthodontic bracket in accordance with the present invention;
• FIG. 100[0141]dis a cross-sectional view of an alternative embodiment of a locking shutter retainer for the orthodontic bracket of FIG. 100a;
• FIGS. 101[0142]ato101care front elevational, side elevational and top plan views of another embodiment of an orthodontic bracket in accordance with the present invention;
• FIG. 101[0143]dis a plan view of a locking shutter used in the orthodontic bracket of FIG. 101ain an unfolded condition;
• FIGS. 102 and 103 are front and side elevational views of another embodiment of an orthodontic bracket in accordance with the present invention;[0144]
• FIG. 104 is a front elevational view of an alternative embodiment of a body for an orthodontic bracket; and[0145]
• FIGS. 105 and 106 are front and side elevational views of yet another alternative of an orthodontic bracket in accordance with the present invention.[0146]
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
• Referring now to FIGS. 1 and 2, a pre-engaging twin orthodontic bracket is shown and is generally indicated to by[0147]reference numeral10. As can be seen,orthodontic bracket10 includes abody12 and alingual mounting pad14 attached to the body. The mountingpad14 has a lingual surface to be attached to a tooth. A pair of laterally spacedgingival tie wings16 and a pair of laterally spacedocclusal tie wings18 extend from a labial surface of thebody12. Thegingival tie wings16 and theocclusal tie wings18 curve lingually. Anarchwire slot20 extends mesiodistally across the body and between the gingival and occlusal tie wings at opposed mesial and distal sides of the body and opens labially to receive anarchwire22. Thearchwire slot20 is interrupted in theinterwing region12′ of the body. A V-shaped deflection notch is formed in the gingival wall of thearchwire slot20 at its mesial and distal ends extends to define mesial and distal bevelled deflection surfaces24 above the archwire slot. Restinggrooves26 are formed in the labial surface of the wings15 below thearchwire slot20.
• A[0148]shutter30 formed of resilient stainless steel is pivotally mounted on theocclusal tie wings18 and is movable between a closed position where access to thearchwire slot20 is inhibited and an open position where access to the archwire slot is permitted (see FIGS. 2aand2b). One end30aof theshutter30 is accommodated inundercuts34 defined by theocclusal tie wings18. The end30aof theshutter30 accommodated by theundercuts34 generally resembles an open “D” and is configured to remain in theundercuts34 throughout movement of the shutter between the open and closed positions. As theshutter30 moves between the open and closed positions, the end30aof the shutter translates within theundercuts34. An aperture30bis formed in theshutter30 to accommodate a tool to facilitate opening of the shutter.
• The[0149]shutter30 curves labially and gingivally around theocclusal tie wings18 and then curves lingually towards thearchwire slot20. When theshutter30 is in the closed position and the archwire applies a labially directed force to theshutter30, thegingival end36 of theshutter30 contacts the deflection surfaces24 to inhibit the shutter from being accidentally removed from thearchwire slot20. At the same time, thelingual surface38 of theshutter30 contacts thearchwire22 to urge it continuously into thearchwire slot20. When theshutter30 is pivoted and translated to remove it from thearchwire slot20, thegingival end36 can be accommodated by the restinggrooves26 to hold the shutter in the open position although this is not necessary as shown by the dotted line in FIG. 2b. This is due to the fact that as thecompressed shutter30 is opened, it flexes over theocclusal tie wings18 as the shutter pivots and translates in theocclusal undercuts34 to maintain the shutter open. Theshutter30 can be closed using a finger by simply pushing on the shutter until thegingival end36 of the shutter enters thearchwire slot20 with thelingual surface38 in contact with thearchwire22. Theshutter30 can be opened by inserting a one or two prong ligature director into the aperture30band applying an occlusally directed force on the shutter in theinterwing region12′ of thebody12.
• The design of the[0150]shutter30 is such that arectangular archwire22 is seated to apply torque to thearchwire slot20 depending on the rectangular cross-sectional shape of thearchwire22. The continuous active seating or biasing of thearchwire22 by theshutter30 provides for accurate tooth movement. Referring now to FIGS. 3aand3b, atooth40 with anorthodontic bracket10 on it is shown. In FIG. 3a, thetooth40 is shown in an original “rotated” position while in FIG. 3b, the tooth is shown in a final “straight” position. The designations A and B in FIGS. 3aand3bdenote coupled sets of force vectors applied by theshutter30 on theorthodontic bracket10 and archwire. As can be seen, thearchwire22 in FIG. 3adeflects theshutter30 labially on the right side reducing the initial force and moment applied to thetooth40 until the shutter gradually seats itself into thearchwire slot20 as shown in FIG. 3bwith less patient discomfort.
• Referring now to FIG. 4, an[0151]orthodontic bracket10 is shown on atooth40. The occlusal edges of theorthodontic bracket10 are preferably parallel to the incisal edges and parallel to the archwire slot. Twoscribe lines44 on theorthodontic bracket10 delineate thelong axis46 of thetooth40 for ideal placement of the orthodontic bracket. Also, the external lingual surface of the mountingpad14 is angulated or biased to assist alignment and placement of theorthodontic bracket10 against the long axis of the tooth. Larger brackets may be used for larger molars.
• Referring now to FIG. 5, an alternative embodiment of an orthodontic bracket is shown and is generally indicated to by reference numeral[0152]10a. In this embodiment, like reference numerals will be used to indicate like components of the first embodiment with an “a” added for clarity. As can be seen, the shutter24ais received in undercuts34adefined by the occlusal tie wings18a. The shutter30ahas anaperture51 formed in it to receive a tool and facilitate pivoting of the shutter from the closed to open positions using a tool. A hollowvertical slot52 is provided on the body12ain the interwing region12a′. Thehollow slot52 allows the orthodontic bracket10ato provide for more tooth inclination, torque control and overcorrection than prior art orthodontic brackets.
• Referring now to FIGS.[0153]6 to10, yet another embodiment of a pre-engaging twin orthodontic bracket is shown and is generally indicated to byreference numeral110. As can be seen,orthodontic bracket110 includes abody112 and alingual mounting pad114 attached to the body. The mountingpad114 has a lingual surface to be attached to a tooth. A pair of laterally spacedgingival tie wings116 and a pair of laterally spacedocclusal tie wings118 extend from a labial surface of thebody112. Thegingival tie wings116 and theocclusal tie wings118 curve lingually. Ahorizontal crossbar117 extends across theinterwing region112′ of thebody112 and interconnects theocclusal tie wings118. Aball hook119 extends from one of thegingival tie wings116.
• The[0154]gingival surface115 of the body in theinterwing region112′ between thegingival tie wings116 is convex and is generally semi-elliptical. The labial surface of the body in theinterwing region112 has anotch150 formed in it. Thegingival tie wings116 are bevelled as indicated byreference numeral121. Anarchwire slot120 extends mesiodistally across thebody112 and between the gingival and occlusal tie wings located at opposed mesial and distal sides of the body and opens labially to receive anarchwire122. The occlusal wall of thearchwire slot120 is continuous and is constituted by theocclusal tie wings118 and thecrossbar117. The occlusal wall of thearchwire slot120 has a notch formed in it to define twodeflection surfaces124 and126 respectively.Deflection surface124 is constituted by a labial bevel whiledeflection surface126 is constituted by a lingual bevel.
• Looking at FIGS. 7 and 10, it can be seen that a[0155]curved groove128 is formed in thegingival tie wings116 andinterwing region112′ of the body and extends mesiodistally. Thegroove128 is spaced above the gingival surface of thebody112 and accommodates apivot pin130. Thepivot pin130 is bonded to thegingival tie wings116 by suitable means such as brazing, soldering, welding or the like. Ashutter132 resembling an inverted “T” in front elevation is pivotally mounted on thepivot pin130 in theinterwing region112′ and is movable between a closed position where access to thearchwire slot120 is inhibited and an open position where access to thearchwire slot120 is permitted.
• Referring now to FIGS. 11[0156]aand11b, theshutter132 is better illustrated. As can be seen, theshutter132 includes a lingually curvedupright stem134 and atransverse arm136 at the occlusal end of the stem. The edges of the shutter are curved at the intersection between thestem134 andtransverse arm136 to strengthen the shutter. Thestem134 curves over itself at its gingival end and terminates in an open D-shapedcup138 which partially surrounds thepivot pin130 and is accommodated in an undercut39 formed in theinterwing region112′ occlusally of the pivot pin to secure the shutter to theorthodontic bracket110. A generallytriangular aperture140 is formed in thestem134 to receive a tool to facilitate pivoting of theshutter132 from the closed position to the open position. The occlusal portion of thetransverse arm136 of the shutter is generally convex when viewed in profile and is dimensioned to be accommodated in thearchwire slot120. Theocclusal edge142 of thetransverse arm136 is slightly concave.
• The[0157]archwire slot120 is designed to accommodate circular cross-section orrectangular cross-section archwires122. When thearchwire122 is positioned in the archwire slot and the shutter is closed, the lingual surface of theshutter132 contacts the archwire to urge it continuously against the body112 (see FIG. 9a). Thedeflection surface126 inhibits theshutter132 from being accidentally removed from thearchwire slot120 when thearchwire122 applies a labially directed force to the archwire. When it is desired to open theshutter132, a tool is inserted into theaperture140 and is accommodated by thenotch150. The tool can then be used to pivot the shutter with sufficient force so that theocclusal edge142 of thetransverse arm136 passes over thedeflection surface126 and so that the end of thecup138 rotates into the undercut139 allowing theshutter132 to open.
• During this pivotal movement of the[0158]shutter132, the convex interwinggingival surface115 of thebody112 and the flexing of the initially compressed shutter over theconvex surface115 as theshutter132 pivots around thepivot pin130 with the end of the shutter in the notch as shown in FIG. 9b, maintains the shutter in an open condition. The undercut139 occlusally of thepivot pin130 provides sufficient clearance for theshutter132 to pivot freely in a rotary fashion.
• Although the[0159]shutter132 has been described as having a D-shapedcup138 to surround thepivot pin130, the shutter can curl back around itself to surround substantially thepivot pin130 between the gingival tie wings. Also, although the pivot pin has been described as being accommodated in curved slots and bonded to the orthodontic bracket, it should be apparent to those of skill in the art that the pivot pin may be integrally formed with and extend between the gingival tie wings.
• Although the gingival surface of the body in the interwing region has been described as being semi-elliptical, it should be appreciated that other surface configurations are suitable. Also, although the pivot pin has been described as being accommodated in a groove extending across the gingival tie wings and the body, the pivot pin may only extend between the gingival tie wings in the[0160]interwing region112′ making the gingival tie wings more accessible. Also, although the shutter has been shown as pivoting about a pivot pin extending between the gingival tie wings, the pivot pin may extend between the occlusal tie wings.
• Referring now to FIGS.[0161]12 to15, yet another embodiment of an orthodontic bracket is shown and is generally indicated to byreference numeral220. As can be seen,orthodontic bracket220 includes abody222 and a lockingshutter224. For illustrative purposes, theorthodontic bracket220 is configured for a maxillary tooth but it can be appreciated that theorthodontic bracket220 could be used on a mandibular tooth.
• [0162]Body222 includes alingual mounting pad226 having a lingualtooth attaching surface228 adapted for direct attachment to a tooth or to a pad that may be attached to a tooth. A pair of laterally spacedocclusal tie wings234 and a pair of laterally spacedgingival tie wings236 project from a labial surface of thebody222. Eachtie wing234,236 curves lingually to define an undercut238 for receiving a ligature. Anarchwire slot240 extends mesiodistally across thebody222 and between the occlusal and gingival tie wings at opposed mesial and distal sides of the body. Thearchwire slot240 accommodates anarchwire242. Thearchwire slot240 has a pair ofopposed surfaces244,246 at its mesial and distal ends. Inverted V-shapeddeflection notches248 are provided in thegingival tie wings236 above the archwire slot. Thedeflection notches248 are provided to receive agingival edge250 of the lockingshutter224 in the closed position.
• The locking[0163]shutter224 extends between the occlusal and gingival tie wings at opposed mesial and distal sides of thebody222 and across thearchwire slot240. The lockingshutter224 has abody252 which is cranked as indicated at254 to provide a pair of relativelyinclined portions256,258. Occlusal edge260 of theshutter body252 is provided with a recess262 (as seen in FIGS. 12 and 14) so as to define a pair of downwardly projectingarms264,266 that overlie respective ones of theocclusal tie wings234 when theshutter224 is in a closed position. Anaperture267 is centrally positioned on theshutter224 to accommodate a tool to facilitate movement of the locking shutter.
• The locking[0164]shutter224 is retained on theorthodontic bracket220 by means of an off-center pivot pin268 that passes through an aperture (not shown) formed in thearm264 and is secured to theocclusal tie wing234. Theshutter224 is thus able to slide in a generally occlusal-gingival plane about thepin268 as indicated byarrow269 in FIG. 14.
• An[0165]indentation272 is formed in thearm266 and acorresponding dimple274 formed in the underlyingocclusal tie wing234.Arm266 includes a buccally-extending return276 that passes around the distal side of theocclusal tie wing234 and has a retainingplate278 that is received within aslot280 formed in the side of theocclusal tie wing234.
• The[0166]indentation272 cooperates with thedimple274 to form a detent which inhibits pivotal movement of theshutter224 about thepivot pin268 and retains the lockingshutter224 in the closed position. The retainingplate278 cooperates with theslot280 and the shutter cooperates with thedeflection notches248 to inhibit labial movement of the locking shutter when in the closed position and an archwire applies a labially directed force to the shutter so that the lockingshutter224 retains thearchwire242 within thearchwire slot240.
• To open the locking[0167]shutter224, it is simply necessary to overcome the detent provided by theindentation272 anddimple274 and rotate the lockingshutter224 about thepivot pin268. Access to thearchwire slot240 is thus obtained. Similarly, to close the lockingshutter224, it is simply necessary to pivot the locking shutter about thepivot pin268 so that thegingival edge250 engages thedeflection notches248 and theindentation272 engages thedimple274. The lockingshutter224 is thus held securely and cooperates with thearchwire242 to apply the requisite forces to the archwire within the archwire slot.
• An alternative embodiment of an orthodontic bracket is shown in FIGS. 16[0168]ato17band is generally indicated to by reference numeral220a. In this embodiment, like components of the previous embodiment will be identified with like reference numerals, with the suffix “a” added for clarity.
• As can be seen, the locking shutter[0169]224ais pivotally secured to aboss290 that extends between the gingival tie wings236aby way of centrally positioned pivot pin268a. Oneedge292 of the locking shutter224ais arcuate giving the shutter224aa generally semi-circular appearance. Deflection notches248aare formed in the occlusal tie wings234aadjacent the archwire slot240a. It will be noted that the labial surfaces of the occlusal tie wings234aare labially protrusive so that thearcuate edge292 of the locking shutter224ais aligned with the deflection notches248a.
• Dimples (not shown) are formed on each of the gingival tie wings[0170]236aand corresponding indentations272aare formed on the locking shutter224a. The dimples and indentations272acooperate when the locking shutter224ais either in the open or closed positions to retain the locking shutter in that position. An aperture267ais provided in the shutter to receive a tool and facilitate movement of the shutter224a. The locking shutter224acan be pivoted about pivot pin268aso as to bring thearcuate edge292 into engagement with the notches248aas shown in FIGS. 17aand17bby overcoming the detent provided by the indentations272aand dimples. In this position, the locking shutter224ais effective to inhibit removal of an archwire from the archwire slot240a. The locking shutter224acan be readily moved to the open position by rotating the locking shutter about the pivot pin268ato allow access to the archwire slot240aas shown in FIG. 16a.
• Another alternative arrangement of an[0171]orthodontic bracket220′ is shown in FIGS.18 to20. In this embodiment, like reference numerals will be used to indicate like components of the embodiment of FIGS.12 to15 with the suffix “′” added for clarity. In this embodiment, the lockingshutter224′ is relieved and is generally C-shaped to provide a pair ofarms264′ and266′. Similar to the previous embodiment, the lockingshutter224′ is pivotally secured to aboss290′ extending between thegingival tie wings236′ by way of apivot pin268′. Adimple274′ is provided on bothgingival tie wings236′.Indentations272′ on thearms264′ and266′ co-operate with thedimples274′ with the detent formed between the indentations and dimples maintaining the lockingshutter224′ in the open position. Thenotches248′ define deflection surfaces to inhibit labial movement of theshutter224′ and its removal from thearchwire slot240′ when theshutter224′ is in the closed position and an archwire applies a labially directed force to the shutter. In order to move the shutter from the open to closed position, it is necessary to overcome the detent provided by theindentations272′ and thedimples274′ and pivot theshutter224′ about thepivot pin268′.
• In embodiments of the orthodontic brackets illustrated in FIGS.[0172]12 to20, it will be observed that movement of the locking shutter between open and closed positions is obtained by simple rotation of the locking shutter about the pivot pin so that the locking shutter remains captive to the body but at the same time is securely held in the closed and/or open positions by the action of the detent formed between the indentations and dimples.
• A further embodiment of an orthodontic bracket is shown in FIGS.[0173]21 to24, in which like reference numerals will be used to denote like components of the embodiment of FIGS.12 to15 with a suffix ‘c’ added for clarity. As can be seen, acircular track500 is formed on the mesial, distal, occlusal and gingival sides of the orthodontic bracket220c. Thecircular track500 passes through the occlusal and gingival tie wings234cand236crespectively to intersect the archwire slot240c.Bores501 are formed in thecircular tracks500 in the mesial and distal sides of the gingival tie wings236cslightly above the archwire slot240c. The archwire slot240cis offset occlusally so that the gingival tie wings236care longer than the occlusal tie wings234c.
• The[0174]track500 receives a shutter in the form of apart circular clip502 having acircular protrusion504 at one end. Theclip502 is slidable in thetrack500 but provides a friction grip against the track to inhibit unintentional movement. Thecircular protrusion504 is accommodated by one of thebores501 to hold theclip502 in either the closed or open positions.
• The[0175]clip502 may be rotated in thetrack500 between an open position in which access to the archwire slot240cis available (see FIG. 24) and a closed position in which access is inhibited (see FIGS. 22 and 23). As can best be seen in FIG. 22, the offset of the archwire slot240callows theclip502 to overlie the archwire slot240cto retain an archwire within the archwire slot. Rotation of theclip502 through approximately 180 degrees moves the clip to the position shown in FIG. 24 at which the archwire slot240cis open and access to the archwire is provided. Thecircular protrusion504 facilitates rotation of theclip502 between open and closed positions, with the friction between the clip and thetrack500 and the cooperatingprotrusion504 and bore501 retaining theclip502 in the desired position.
• A still further embodiment of an orthodontic bracket[0176]220bis shown in FIGS.25 to27 in which like reference numerals will be used to denote like components of the embodiment of FIGS.12 to15, with a suffix “b” added for clarity. As can be seen, the shutter224bis slidable within aslot510 formed in each of the occlusal wings234b. A U-shaped strap512 is secured to the labial face of shutter224band extends through aguide slot514 and a washer515 in the base of each of theslots510. Acoil spring516 is positioned in each slot beneath the shutter224band surrounds each arm512aof the strap512. The arms512aare cranked slightly above the coil springs516 toward the archwire slot240bas indicated to byreference numeral518. Thesprings516 bias the shutter224bto a closed position in which the gingival edge250bof the shutter224bengages the notches248b.
• The labial surface of the shutter[0177]224bcarries awedge520 that cooperates with acomplementary recess522 formed in the slots. Thewedge520 retains the shutter224bin the open position and may be released by application of a force to the bight512bof the strap512 to release the shutter224bunder the action of thesprings516. The shutter224bis thus retained in the closed position to resist labial movement of an archwire242bin the archwire slot240b. The spring loaded shutter224bmay also be applied in a similar manner to two single orthodontic brackets or a 3 wing orthodontic bracket.
• A still further embodiment of an orthodontic bracket[0178]220dis shown in FIGS.28 to31 where like reference numerals will be used to indicate like components of the embodiment illustrated in FIGS.12 to15 with the suffix “d” added for clarity. In this embodiment,grooves530 are formed in the mesial and distal sides of the body222d. Eachgroove530 extends through the gingival and occlusal tie wings236dand234d. Thegrooves530 terminate inblind bores532 in the gingival tie wings236d. Blind bores534 are also formed in thegrooves530 in the occlusal tie wings236dadjacent the archwire slot240d(see FIG. 31). The occlusal surfaces of the occlusal tie wings236dare undercut to provide alateral groove536 that extends mesiodistally between the occlusal tie wings.
• A shutter[0179]224din the form of a generally U-shaped clip538 is formed with a pair ofouter arms540 interconnected by alateral bight542. The ends of thearms540 are formed with inwardly-directedprojections544 for receipt within thebores532 or534.
• A[0180]support arm546 is secured to thelateral bight542 and is jogged to provide a horizontal arm546abetween a pair of vertical arms546band546crespectively. One of the vertical arms546cis received within avertical slot548 in the body220dand maintains alignment of the clip538 as it is moved between the open and closed positions. Theslot548 is located in the interwing region of the body222dto provide uniform support.
• The clip[0181]538 is assembled on the orthodontic bracket220dso that thearms540 are received within therespective grooves530. Theprojections544 are received within the blind bores534 so that the archwire slot240dis open for receipt of an archwire as shown in FIG. 30a. With the archwire242dinserted into the archwire slot240aas shown in FIG. 30b, the clip538 may be advanced along thegrooves530 until theprojections544 are received within the blind bores532. In this position, thelateral bight542 is received within thelateral groove536 to provide further security for the clip538. The vertical arm546cand slot548 serve to guide and align the clip538 during sliding motion to facilitate the relative movement between the clip and the orthodontic bracket220d.
• A further embodiment of an orthodontic bracket[0182]220eis shown in FIGS.32 to36. In this embodiment like reference numerals will be used to denote like components of the embodiment of FIGS.12 to15 with a suffix “e” added for clarity. In the embodiment of FIGS.32 to36,grooves560 are formed in the occlusal tie wings234eonly. The shutter224eincludesside flanges562 that have inwardly directedprotrusions564 to engage thegrooves560. The shutter224ehas a pair of lingually angulated occlusal arms264eand266eand a centrally positionedgingival arm566 defined partly by a pair ofslits568 in the shutter224e(best seen in FIG. 36). Thegingival arm566 is recurved in a labial direction as indicated by reference numeral569 and is resilient to engage the labial notches248eat the mesial and distal ends of the archwire slot240eand inhibit labial movement of shutter224ewhen an archwire applies a labially directed force to the shutter.Protrusions570 are provided on the sides of the shutter224eto form a handle and facilitate sliding movement of the shutter224ebetween the open and closed positions. Again therefore, a sliding shutter is provided on the orthodontic bracket220eto retain an archwire in the archwire slot240e.
• In a further embodiment shown in FIG. 37, a known orthodontic bracket[0183]220fsold under the trade name “SPEED” is shown and includes a pair of occlusal tie wings234fbelow a shutter224fand a pair of gingival tie wings above the shutter224fto provide a twin orthodontic bracket. The gingival tie wings can be spaced further apart to make the orthodontic bracket more symmetrical.
• Referring now to FIGS.[0184]38 to41, still yet another embodiment of an orthodontic bracket is shown. In this embodiment, like reference numerals will be used to denote like components of the embodiment of FIGS.12 to15 with a “1000” added for clarity. As can be seen, theorthodontic bracket 1220 is similar to one of the orthodontic brackets disclosed in Applicant's U.S. Pat. No. 5,474,445 issued on Dec. 12, 1995, the contents of which are incorporated herein by reference. In this embodiment, aprojection1001 is formed on thegingival surface1003 of thebody1222 in the interwing region. Theshutter1224 generally resembles a cruciform and has agingival arm1005 with an inverted doghouse shapedaperture1267 in it to accommodate theprojection1001 and retain theshutter1224 in the closed position. The shape of theaperture1267 also permits a tool to enter the aperture so that a labially directed force can be applied to theshutter1224 using the tool to release theshutter1224 from theprojection1001. The mesial anddistal arms1007 and1009 respectively of theshutter1224 curve lingually into thearchwire slot1240. Thearms1007 and1009 are resilient and are somewhat flattened when contacting a full dimensionrectangular archwire1242 accommodated in thearchwire slot1240 to apply a bias to move thearchwire1242 into the base of the archwire slot. In this way, a continuous rotation action and torque is applied to the archwire whether round or rectangular (even where that archwire is of relatively small cross-sectional dimension) to apply a continuous force to the tooth through theorthodontic bracket1220. Theocclusal arm1011 of theshutter1224 curves labially to define a single loop which surrounds apivot pin1013 to secure theshutter1224 to theorthodontic bracket1220 and to provide a shutter with a continuous smooth lingual surface.
• FIG. 41[0185]ashows an alternative embodiment of the shutter and pivot pin design. In this embodiment, a dimple1013ais formed in thepivot pin1013 and an indentation1224ais provided in theshutter1224. The indentation1224aand dimple1013acooperate when the shutter is in a closed position to provide further security to inhibit accidental opening of the shutter.
• A similar arrangement of an[0186]orthodontic bracket2220 to that described above is shown in FIGS.42 to45. In this embodiment, like reference numerals will be used to denote like components of the embodiment of FIGS.12 to15 with a “2000” added for clarity. As can be seen, theorthodontic bracket2220 also has ashutter2224 generally resembling a cruciform. Thegingival arm2005 of theshutter2224 has a doghouse shapedaperture2267 in it to accommodate aprojection2001 and retain theshutter2224 in the closed position. Unlike the previous embodiment, the mesial and distal arms2007 and2009 on theshutter2224 are relatively rigid. A spring member in the form of aribbon700 is located on the lingual surface of theshutter2224 and extends mesiodistally. Theribbon700 is configured to provide a pair of convexlingually extending formations702 that are aligned with the occlusal and gingival tie wings at opposed mesial and distal sides of the body2222 and thus bear against anarchwire2242 located in thearchwire slot2240. Thecentral portion704 of theribbon700 is secured to theshutter2224 with thelateral extremities706 of the ribbon being free to slide horizontally over the lingual surface of theshutter2224 and thereby allow flexure of theformations702. In this manner, different thicknesses ofarchwires2242 can be accommodated by theorthodontic bracket2220 while still ensuring that a continuous force is applied to the tooth through the orthodontic bracket.
• FIG. 45[0187]aillustrates an alternative embodiment of aribbon700′ for use with theorthodontic bracket2220. In this embodiment, theribbon700′ is secured to the lingual surface of theocclusal arm2011 of theshutter2224 adjacent one of its ends and extends in a gingival-occlusal direction. Theother end706′ of theribbon700′ is free to slide relative to the lingual surface of theshutter2224 as indicated by the dottedline710. Thetong700′ presents aconvex surface702′ which enters thearchwire slot2240 when the shutter is in a closed position to bias thearchwire2242 into the archwire slot.
• FIGS. 46 and 47 illustrate alternative embodiments of[0188]orthodontic brackets1220′ similar to that illustrate in FIGS.38 to41. In these embodiments, like reference numerals will be used to indicate like components of the embodiment of FIGS.38 to41 with a “′” added for clarity. In the embodiment of FIG. 46, theshutter1224′ has short mesial anddistal arms1007′ and1009′ which curve lingually into thearchwire slot1240′ to apply a bias to anarchwire1242′ accommodated by thearchwire slot1240′. In the embodiment of FIG. 47, theshutter1224′ has longer mesial anddistal arms1007′ and1009′ which curve lingually into thearchwire slot1240′ to apply a bias to anarchwire1242′ accommodated by thearchwire slot1240′.
• Referring now to FIGS.[0189]48 to52, still yet another embodiment of an orthodontic bracket3220dis shown similar to that shown in FIGS.28 to31. In this embodiment, like reference numerals will be used to denote like components of the embodiment of FIGS.28 to31 with a “3000” added for clarity. As can be seen, the orthodontic bracket3220dcan be modified to provide a continuous seating action bias to an archwire accommodated in the archwire slot. In this arrangement, a spring member in the form of aresilient shim720 is attached to the vertical arm3546bof the support arm3546. Theshim720 thus projects gingivally from the labial edge of the horizontal arm3546aso as to be spaced from the lingual vertical arm3546c. Theshim720 has a jog directed lingually toward the archwire slot3240dand presents a generallyconvex surface722 towards the archwire slot3240d. Thegingival edge724 of theshim720 recurves labially.
• As the[0190]arms3540 slide within theslots3530 to the move the clip3538 to a closed position as shown in FIG. 49, theconvex surface722 of theshim720 engages the archwire3242dand provides a continuous biasing action against the archwire (best seen in FIG. 50). As may be seen in FIG. 51, the resilience of theshim720 allows the orthodontic bracket3220dto accommodate different sizes and configurations of archwires3242dwhile maintaining a continuous action against the archwire.
• Referring now to FIGS.[0191]53 to55, still yet another embodiment of anorthodontic bracket4220 is shown similar to that shown in FIGS.12 to15. In this embodiment, like reference numerals will be used to denote like components of the embodiment of FIGS.12 to15 with a “4000” added for clarity. As can be seen, theorthodontic bracket4220 can be modified to provide a continuous bias to an archwire accommodated in the archwire slot. In this embodiment, a spring member in the form of aresilient shim730 is secured to the lingual surface of theshutter4224 adjacent the interwing region of thebody4220. Theshim730 is integrally formed with theshutter4224 and is folded lingually about theocclusal edge4260 of the shutter between thearms4264 and4266 respectively. Theshim730 is curved lingually to present a generallyconvex surface732 spaced from theshutter4224 and itsend734 recurved to form a smooth lip engaged with the lingual face of theshutter4224. Theend734 of theshim730 is free to slide relative to theshutter4224 when the convex surface731 is flattened due to contact with anarchwire4242 in thearchwire slot4240. Theshim730 is thus able to continuously exert a corrective force upon different configurations ofarchwires4242 within thearchwire slot4240 when theshutter4224 is in the closed position.
• Referring now to FIGS.[0192]56 to58, still yet another embodiment of an orthodontic bracket5220bis shown similar to that shown in FIGS.25 to27. In this embodiment, like reference numerals will be used to denote like components of the embodiment of FIGS.25 to27 with a “5000” added for clarity. As can be seen, the orthodontic bracket5220bcan be modified to provide a continuous bias to an archwire accommodated in the archwire slot. In the arrangement shown, a spring member in the form of aresilient shim740 is formed on the lingual face of the shutter5224bin the archwire slot5240b. Theshim740 is formed with a convexlingual surface742 that engages an archwire5242bwhen the shutter5224bis in the closed position. Theshim740 is secured to the shutter5224badjacent its occlusal end only and therefore, thegingival end744 of theshim740 is free to slide relative to the shutter5224b. In this manner, theshim740 may flex to accommodate different sizes and shapes of archwires5242baccommodated in the archwire slot5240bto provide a continuous action on the archwire wire.
• Referring now to FIGS.[0193]59 to62, still yet another embodiment of an orthodontic bracket6220eis shown similar to that shown in FIGS.32 to36. In this embodiment, like reference numerals will be used to denote like components of the embodiment of FIGS.32 to36 with a “6000” added for clarity. As can be seen, the orthodontic bracket6220ecan be modified to provide a continuous bias to an archwire accommodated in the archwire slot. In the arrangement shown, a spring member in the form of ashim750 is secured to the lingual surface of the shutter6224eand presents aconvex surface752 toward the archwire slot6240eto engage an archwire6242bin the same manner as described above to provide a continuous action on the archwire wire. Thegingival edge754 of the shim is free to slide relative to the lingual surface of the shutter6224e.
• A continuously acting orthodontic bracket may also be provided with self-locking labial brackets such as those shown in U.S. Pat. No. 5,094,614 to Wildman, the contents of which are incorporated herein by reference. As shown in FIGS.[0194]63 to71, theorthodontic bracket7220 has a pair ofwings7242 with anarchwire slot7240 to receive anarchwire7242.
• A[0195]shutter7224 is located between the gingival and occlusal tie wings located at opposed mesial and distal sides of the body7222 and includes acentral body portion7322 encompassed by alocking spring7324. The mesial and distal edges of theshutter body7322 are received withingrooves7326 so that theshutter7224 may slide between open and closed positions. Thegrooves7326 haveundercuts7328 that terminate atsteps7330 in the occlusal andgingival tie wings7234 and7236 respectively. Thesteps7330 receive one end of aspring7324. The opposite ends are formed as an occlusal tail. A spring member in the form of aresilient shim760 is secured to thetail7332 so as to be spaced from the retainingspring7324. Alingual step7235 accommodates theshim760 from a lingual aspect. Theshim760 thus engages anarchwire7242 in thearchwire slot7240 when theshutter7224 is in the closed position in a resilient manner to provide a continuous biasing action against the archwire as shown in FIG. 6b. Thestep7330 retains theshutter7224 in the closed position with theresilient shim760 biased against thearchwire7242. As shown in FIG. 67, theshim760 may be secured to thetail7332 as a separate structure. Alternatively, as shown in FIG. 69, theshim760 may be formed on thetail7332 of aliner layer7334 that encompasses thebody7322. Thespring7324 extends over the upper edge of thebody7322 and terminates above the upper edge of theshim760. Theshim760 is thus free to flex to accommodate different sizes and dispositions of archwires while providing a continuous action on the archwire.
• Similarly, as shown in FIG. 70, the[0196]shim760 may be secured at its upper edge to thespring7324 with the lower edge free of the tong to slide relative to the shutter upon flexure of theshim760.
• An alternative arrangement for the[0197]shim760 is shown in FIGS. 72 and 73. In this embodiment, theresilient shim760 is defined in the lingual aspect of the outer layer of thespring7324. Three sides of theshim760 are defined byslots764 cut into the lingual aspect of the outer layer of the spring to define the periphery of theshim760. The resultant shim defines an inwardlyconvex surface762 that resiliently engages the archwire. Naturally, such ashim760 may be formed integrally with thesprings7324 to facilitate manufacture.
• A further modification of an existing[0198]orthodontic bracket7220′ is shown in FIGS.74 to78 in which the orthodontic bracket known as the Damon bracket and shown in U.S. Pat. No. 5,439,378, the contents of which are incorporated herein by reference, is modified to provide a spring member in the form of aresilient shim770 on the lingual surface of theshutter7224′.Shutter7224′ may be extended occlusally to accommodate theshim770 which in this embodiment is formed by folding a continuous extension of theshutter7224′ back upon itself. Theshim770 presents a convex surface772 which enters thearchwire slot7240′ when theshutter7224′ is in a closed position. Oneend744 ofshim770 is free to slide relative to theshutter7224′. In this manner, theshim770 may flex to accommodate different sizes and shapes ofarchwires7242′ accommodated in thearchwire slot7240′ to provide a continuous action on the archwire.
• As those of skill in the art will appreciate, in the embodiments illustrated in FIGS.[0199]38 to78, the spring member may be formed as a separate member and attached to the shutter adjacent either its gingival or occlusal ends in a manner so that it extends into the archwire slot to bias the archwire. Alternatively, the spring member may be integrally formed with the shutter by a folding portion of the shutter about an edge. If the spring member is to be integrally formed with the shutter, a continuous extension of the shutter is typically folded about either a gingival or occlusal edge of the shutter and is configured so that it extends into the archwire slot to bias the archwire.
• Referring now to FIGS.[0200]79 to82, still yet another embodiment of an orthodontic bracket8220 is shown similar to that shown in FIGS. 16ato17a. In this embodiment, like reference numerals will be used to denote like components of the embodiment of FIGS. 16ato17bwith a “8000” added for clarity. As can be seen, the resilient locking shutter8224ais pivotally secured to aboss8290 that extends between the gingival tie wings8236aby way of a centrally located pivot pin8268a. Theboss8290 is located on a lingually bevelled labial surface of the body822a. Thus, the shutter8224ais inclined. One edge8292 of the locking shutter8224ais arcuate to give the shutter a generally semi-circular appearance. Deflection notches8248aare formed in the archwire slot8240aadjacent the occlusal tie wings8234a.
• Dimples (not shown) are formed on each of the gingival tie wings[0201]8236aand corresponding indentations8272aare formed on the locking shutter8224a. The dimples and indentations8272acooperate when the locking shutter8224ais either in the open or closed positions to retain the locking shutter in that position. An aperture8267ais provided in the shutter8224ato receive a tool and facilitate movement of the shutter8224a. The locking shutter8224acan be pivoted about pivot pin8268aso as to bring the shutter8224ainto engagement with the archwire8242ain the archwire slot8240aas shown in FIG. 81 by overcoming the detent provided by the indentations8272aand dimples. In this position, the locking shutter8224ais effective to inhibit removal of an archwire8242 from the archwire slot8240aand provides a continuous action on the archwire. The locking shutter8224acan be readily moved to the open position by rotating the locking shutter about the pivot pin8268ato allow access to the archwire slot8240a. As can be seen in FIG. 82, when alarger archwire8242 is accommodated by the archwire slot8240a, the shutter8224aflexes to accommodate the archwire yet provide a continuous action on the archwire. The deflection notches8248aand the angulated orientation of the shutter8224ainhibit the shutter8224afrom moving labially out of the archwire slot8240a.
• Another embodiment of an[0202]orthodontic bracket9220 utilizing an alternative shutter structure is shown in FIGS.83 to87. In this embodiment, like reference numerals will be used to denote like components of the embodiment of FIGS.12 to15 with a suffix ‘9000’ added for clarity. As shown in FIGS.83 to87, theshutter9224 is pivotal and is formed from awire9001 bent into a generally cruciform outline. Thewire9001 has opposite ends that are turned over to provide oppositely-directedtails9003 and9005. Thetails9003,9005 extend parallel to a common axis but are offset from one another.
• Each of the[0203]tails9003,9005 is received in arespective bore9007 formed in each of theocclusal tie wings9234. Thetails9003,9005 are free to rotate within the respective bores to permit pivotal movement of theshutter9224.
• The[0204]wire9001 defines a pair of oppositely-directedarms9009,9011 which extend across thearchwire slot9240. Ahorizontal recess9013 is formed in each of thegingival tie wings9236 adjacent thearchwire slot9240 to provide an abutment surface to limit pivotal movement of theshutter9224 towards thearchwire slot9240.
• The[0205]wire9001 between thearms9009,9011 is formed into a rearwardly-projectinghook9015 as can best be seen in FIG. 84 and is received withingroove9017. Anextension9019 is formed on the gingival surface of thebody9222 and passes through thehook9015 when theshutter9224 is in a closed position to provide a frictional fit between thehook9015 andbody9222 and retain the shutter in the closed position.
• As shown in FIG. 84, the[0206]hook9015 retains theshutter9224 against thearchwire9242 and inhibits relative movement between the archwire and thebody9222 of theorthodontic bracket9220. To release thearchwire9242, theshutter9224 is caused to pivot about the offsettails9003,9005 to release thehook9015 from the extension9109. As theshutter9224 is rotated, the eccentricity of the axes of rotation of thetails9003,9005 causes a torsional resistance due to flexure of thewire9001 tending to return theshutter9224 to the closed position. This movement is opposed until such time as theshutter9224 goes over center, at which point theshutter9224 becomes biased to the open position as shown in FIG. 87. In this way, theshutter9224 is resiliently biased toward thebody9222 as it is moved towards the closed position but remains in a stable, open position at other times.
• A further embodiment of an[0207]orthodontic bracket9220′ utilizing a wire for ashutter9224′ is shown in FIGS. 88 and 89, where like components of the previous embodiment will be described using like reference numerals with a suffix “′” added for clarity. In this embodiment, theshutter9224′ is formed from awire9001′ having oppositely directedtails9003′,9005′. Each of thetails9003′,9005′ is pivotally received withinbores9007′ which are aligned on a common axis to allow free pivotal movement of theshutter9224′. The bores may also be offset as shown in FIG. 83.
• The[0208]wire9001′ between thearms9009′,9011′ is formed as an elongateU-shaped projection9020 and is received within alocking clip9022. As can best be seen in FIG. 89, lockingclip9022 is generally U-shaped with serpentine limbs terminating in outwardly-flared ends9024. Theprojection9020 may be received between the flared ends9024 to force the limbs apart but is then resiliently retained between the limbs in a stable manner. Thelocking clip9022 may alternatively have a generally circular section as shown in FIG. 90 but it is believed theclip9022 shown in FIG. 89 facilitates insertion of theprojection9020. Again, theshutter9224′ retains thearchwire9242′ within thearchwire slot9240′ when thelocking clip9022 retains theshutter9224′ in a closed position.
• Referring now to FIGS. 91[0209]aand91b,orthodontic tools900 are shown which are suitable to open and close the shutters of the orthodontic brackets. As can be seen, eachorthodontic tool900 comprises acentral body portion902, a nose-shapedportion904 at one end of the body portion for opening the shutter and a generally square corrugated fork-shapedportion906 at the opposite end of thebody portion902 for gripping and guiding archwires lingually into the archwire slots to facilitate closure of the shutters. The fork-shaped portion straddles the outside of the bracket mesially and distally. In use, the nose-shapedportion904 is inserted into the aperture in the shutter and a force is applied to the shutter using thetool900 to move the shutter in the desired manned. In the embodiment of FIG. 91 a, the fork-shapedportion906 is aligned with thebody portion902 while in the embodiment of FIG. 91b, the fork-shapedportion906 is at right angles to the body portion. Other angles between thebody portion902 and the fork-shapedportion906 are of course suitable. Also, the shape of the nose-shapedportion904 can vary to complement the aperture in the shutter.
• Referring now to FIGS. 92[0210]ato92cstill yet another embodiment of an orthodontic bracket is shown and is generally indicated to byreference numeral10010. Theorthodontic bracket10010 includes abody10012 and alingual mounting pad10014 attached to the body. The mountingpad10014 has alingual surface10015 to be attached to a tooth. A pair ofgingival tie wings10016 and a pair ofocclusal tie wings10018 extend from a labial surface of thebody10012. Thegingival tie wings10016 and theocclusal tie wings10018 curve lingually. Both thegingival tie wings10016 and theocclusal tie wings10018 at opposed mesial and distal sides of the body are separated by aninterwing region10019 of thebody10012. Anarchwire slot10020 extends mesiodistally across the body between the gingival and occlusal tie wings at opposed mesial and distal sides of the body and opens labially to receive anarchwire10022. Thearchwire slot10020 is interrupted mesiodistally in theinterwing region10019. A lockingshutter10024 is accommodated byrecesses10026 in the gingival and occlusal tie wings and is moveable between a closed position where the archwire is locked into the archwire slot and access to and the release of thearchwire slot10020 is inhibited, and an open position where access to the archwire slot is permitted.
• Within the[0211]archwire slot10020 is a slot activator in the form of a generally rectangular,resilient spring member10032 formed of suitable material such as for example Nickel-Titanium or spring stainless steel. Thespring member10032 extends mesiodistally along the archwire slot. Thespring member10032 has acentral portion10034 secured to the lingual wall of thearchwire slot10020 such as for example by way of aweld10036 or a sleeve (not shown). Opposed ends of thespring member10032 curve labially towards the lockingshutter10024 to define protrusive mesial anddistal wings10038 and10040. The mesial anddistal wings10038 and10040 of thespring member10032 extend into thearchwire slot10020 starting from the lingual wall of the archwire slot a distance equal to approximately one third to one half of the depth of the archwire slot. Thearchwire slot10020 formed in thebody10012 is mildly deeper than in conventional orthodontic brackets to accommodate the thickness of thecentral portion10034 of thespring member10034.
• In use, when an[0212]archwire10022 is placed into thearchwire slot10020 and the lockingshutter10024 is closed, the mesial anddistal wings10038 and10040 of thespring member10032 contact thearchwire10022 to bias it towards the lockingshutter10024. As shown in FIGS. 92band92c, when a small round archwire is used, thearchwire10022 is biased by thespring member10032 to control and seat the archwire towards the locking shutter. During initial treatment, biasing of thearchwire10022 in this manner provides initial tooth movements to produce accurate rotation corrections and in-out (horizontal plane) movements of teeth. During the middle of treatment, biasing of the archwire in this manner controls and supports bodily tooth movement preventing rotation of teeth as they slide along a straight archwire by a pull force.
• FIG. 92[0213]dshows theorthodontic bracket10010 accommodating a largerectangular archwire10022 in thearchwire slot10020 which is used at the end of treatment. In this case, the labially curved mesial anddistal wings10038 and10040 of thespring member10032 are partially flattened by the archwire but continue to act on the archwire to bias it towards the lockingshutter10024. Biasing thearchwire10022 in this manner applies a labial force on the archwire against the lockingshutter10024 to produce desired root torque in the tooth root and crown.
• Referring now to FIG. 93, still yet another embodiment of an orthodontic bracket is shown and is generally indicated to by[0214]reference numeral10110. In this embodiment, the slot activator is in the form of a generally rectangular, convexresilient spring member10132 formed of spring stainless steel. The mesial anddistal ends10138 and10140 of thespring member10132 are flattened.Distal end10140 of thespring member10132 is secured to the lingual wall of thearchwire slot10120 by way of aweld10136 while themesial end10138 of thespring member10132 is free.
• Although the distal end of the[0215]spring member10132 is shown attached to the body, it should be apparent to those of skill in the art that the mesial end of thespring member10132 may be secured to the body with the distal end of thespring member10132 being free. The length of thespring member10132 is less than the length of thearchwire slot10120 so that the free end of the spring member remains in the archwire slot when thespring member10132 is partially flattened by a large rectangular archwire accommodated by the archwire slot.
• The[0216]orthodontic bracket10110 functions in a similar manner to the previous embodiment. When a small round archwire is placed in thearchwire slot10120 and the locking shutter (not shown) is closed, theconvex spring member10132 biases the archwire10122 towards the locking shutter. When a large rectangular archwire10122 is placed in thearchwire slot10120, the spring member is only partially flattened and biases the archwire towards the locking shutter.
• Referring now to FIG. 94, still yet another embodiment of an orthodontic bracket is shown and is generally indicated to by[0217]reference numeral10210. In this embodiment, the slot activator is similar to that shown in the previous embodiment except that thespring member10232 is oriented to extend occlusiogingivally in theinterwing region10219 between the occlusal andgingival tie wings10218 and10216 respectively. Theocclusal end10250 of thespring member10232 is secured to the body by way of aweld10236 while thegingival end10252 of thespring member10232 is free. Although the occlusal end of thespring member10232 is shown attached to the body, it should be apparent to those of skill in the art that the gingival end of thespring member10232 may be secured to the body with the occlusal end of the spring member being free.
• FIG. 95 illustrates still yet another embodiment of an orthodontic bracket in accordance with the present invention. In this embodiment, the[0218]orthodontic bracket10310 includesmagnetized bars10360 and10362 inserted intorecesses10364 formed in the lingual and gingival walls of thebody10312 defining thearchwire slot10320. Themagnetized bars10360 and10362 are oriented so that they present a magnetic field of the same polarity into thearchwire slot10320. Thearchwire10322 to be accommodated in the archwire slot is magnetized to the same polarity as themagnetized bars10360 and10362 so that the archwire is repelled and biased labially and occlusally in the archwire slot towards the lockingshutter10324. If desired, the locking shutter can be magnetized to the opposite polarity as the archwire to attract it.
• Referring now to FIGS. 96[0219]aand96b, still yet another embodiment of an orthodontic bracket is shown and is generally indicated to by reference numeral10410. In this embodiment, theslot activator10430 is in the form of a pair of spring loadedpistons10470 extending into thearchwire slot10420 and positioned at opposed mesial and distal ends of the archwire slot between the occlusal andgingival tie wings10418 and10416 respectively. Each spring loadedpiston10470 includes a labially extendingpiston head10472 to contact anarchwire10422 in the archwire slot. Acoil spring10474 is accommodated in abore10476 formed through thebody10412 and acts between the mountingpad10414 and the back of thepiston head10472 to bias the piston head in a direction towards the lockingshutter10424. The piston heads10472 are dimensioned to fill approximately one-third to one-half of the vertical dimension of the archwire slot to inhibit the archwire from sliding up or down and behind the piston head.
• Referring now to FIGS. 97[0220]ato97cstill yet another embodiment of an orthodontic bracket is shown and is generally indicated to byreference numeral10510. In this embodiment, the slot activator is in the form of a generally rectangular, stainlesssteel spring member10532 and is located external to thearchwire slot10520. Thespring member10532 includes acentral portion10534 which runs mesiodistally along the lingual wall of thebody10512 and is trapped between thebody10512 and thelingual mounting pad10514. Labially extendingwings10538 and10540 are provided at the mesial and distal ends of thespring member10532 and contact anarchwire10522 extending along thearchwire slot10520 exterior to the archwire slot near the mesial and distal sides of thebody10512. Thus, thespring member10532 in this embodiment is external to thearchwire slot10520 but still biases anarchwire10522 in the archwire slot labially towards the lockingshutter10524. Thelabial extending wings10538 and10540 contact the archwire at a lateral angle greater than 90° to facilitate flattening of the labial wings when a large rectangular archwire is accommodated by thearchwire slot10520.
• In this embodiment, the locking[0221]shutter10524 includes a single loop adjacent one end to surround apivot pin10580 extending between theocclusal tie wings10518. Ahole10582 is provided in the lockingshutter10524 and co-operates with a pair of spaced projections10584 extending upwardly from the gingival surface of the body in the interwing region of the orthodontic bracket. Each projection10584 includes ahead10586 and anundercut stem10588 supporting the head above the gingival surface of the body. The projections10584 are spaced a distance slightly greater than the diameter of thehole10582 so that theheads10586 must be compressed towards one another to fit into the hole. The undercut stems10588 allow the projections10584 to snap back to their original positions once the heads have passed through thehole10582 thereby to lock theshutter10524 in place in a closed position.
• Referring now to FIGS. 98[0222]aand98b, still yet another embodiment of an orthodontic bracket is shown and is generally indicated to byreference numeral10610.Orthodontic bracket10610 is similar to that shown in FIGS. 92ato92dexcept that the ends10638 and10640 of thespring member10632 extend mesiodistally beyond thearchwire slot10620 and contact the archwire10622 exterior to the archwire slot but near the mesial and distal sides of thebody10612.
• FIGS. 98[0223]cand98dillustrate another embodiment of anorthodontic bracket10610′ similar to that shown in FIGS. 98aand98b. In this embodiment, one of thegingival tie wings10616′ has a pair ofgrooves10625 formed in its opposed sides to obviate the need for an upwardly extending hook on the tie wing.
• FIGS. 99[0224]aand99bshow still yet another embodiment of anorthodontic bracket10710. As can be seen,orthodontic bracket10710 is similar to that illustrated in FIG. 94 and includes an occlusiogingivally extending slot activator positioned in theinterwing region10719 between the occlusal andgingival tie wings10718 and10716 respectively. The slot activator is in the form of acurved spring member10732. The spring member passes through a vertical slot1074iformed in thebody10712 of the orthodontic bracket lingual to thearchwire slot10720 and which opens up at the archwire slot. Theocclusal end10738 of thespring member10732 is secured to the occlusal surface of the body such as for example by a weld. Thegingival end10740 of thespring member10732 is free allowing the free end of the spring member to move when the spring member is flattened by anarchwire10722 in thearchwire slot10720 as indicated by the dottedlines10745.
• Referring now to FIGS. 100[0225]ato100cstill yet another embodiment of an orthodontic bracket is shown and is generally indicated to byreference numeral10810.Orthodontic bracket10810 is similar to that shown in FIGS. 97ato97cand includes apivotal locking shutter10824 having a single loop at one end surrounding apivot pin10880 extending between theocclusal tie wings10818. The gingival end of the locking shutter curves occlusally and snaps over abulbous lip10875 formed on the gingival surface of thebody10812 in theinterwing region10819 to maintain the locking shutter in the closed condition. Anopening10877 is provided through the locking shutter to accommodate a tool to facilitate opening of the locking shutter. Amarker10879 is also provided on the labial surface of the locking shutter below the opening. The marker identifies the center of thearchwire slot10820 to facilitate proper placement of the orthodontic bracket on the center of the long axis of a tooth. Themarker10879 can of course be provided on the lockingshutter10824 at any suitable location so as to identify the position of the archwire slot. In this particular embodiment, the marker is in the form of a coloured circle on the labial surface of the locking shutter. It should however be apparent that the marker can be of any other suitable form such as for example an embossed or depressed region or a laser marking on the locking shutter.
• The slot activator in the embodiment is in the form of a pair of[0226]spring members10832. The spring members extend labially along the mesial and distal sides of thebody10812 and contact anarchwire10822 accommodated by thearchwire slot10820 exterior to the archwire slot but near the mesial and distal sides of thebody10812. Thespring members10832 are secured to the body by welds and contact the archwire at a lateral angle greater than 90° to facilitate flattening of thespring members10832 when a large rectangular archwire is accommodated by the archwire slot.
• In the embodiment illustrated in FIG. 10[0227]d, the configuration of the lockingshutter10824′ and thelip10875′ on the gingival surface of thebody10812′ in the interwing region is modified slightly from that shown in FIGS. 100ato100c. In this particular arrangement, the gingival end of the lockingshutter10824′ and thelip10875′ are configured as wedges which snap over one another to maintain the locking shutter in the closed condition. Theopening10877′ in the lockingshutter10824′ accommodates a tool to facilitate pivoting of the locking shutter over thelip10875 to allow the locking shutter to be pivoted to the open condition.
• Referring now to FIGS. 110[0228]ato110dstill yet another embodiment of an orthodontic bracket is shown and is generally indicated to byreference numeral10910. In this embodiment, the orthodontic bracket includes a slot activator in the form of aspring member10932 similar to that shown in FIGS. 98aand98b. The lockingshutter10924 is however of a different configuration. In particular, the lockingshutter10924 is generally T-shaped in front plan and is constituted by a pair ofshutter elements10981 generally overlying one another and retained in proximity byflaps10983 integrally formed on one of the shutter elements and which have been folded over the other of the shutter elements. The locking shutter is pivotal about apivot pin10980 extending between theocclusal tie wings10918 and accommodated byrecesses10997 therein. Aspring10985 is welded to thepivot pin10980 and is also trapped between theshutter elements10981.
• In the closed condition, the locking[0229]shutter10924 is biased by thespring10985, which acts on thepivot pin10980, intonotches10987 formed in the occlusal surfaces of thegingival tie wings10916. When it is desired to release the lockingshutter10924 and move it to an open condition, it is necessary to apply an occlusally directed force on the locking shutter to compress thespring10985 and move the locking shutter occlusally allowing the gingival end of the locking shutter to clear thenotches10987 and pivot to the open condition. Closing the locking shutter is achieved by performing the above steps in reverse.
• Referring now to FIGS. 102 and 103, still yet another embodiment of an orthodontic bracket is shown and is generally indicated to by[0230]reference numeral20010. The orthodontic bracket includes a lockingshutter20024 having a single loop at one end surrounding a pivot pin20080 extending between the occlusal tie wings20018. The lockingshutter20024 is pivotal about the pivot pin20080 between open and closed positions. A locking mechanism is provided on the orthodontic bracket to retain the lockingshutter20024 in the closed condition. The locking mechanism includes an L-shaped arm20025 extending from the free end of the locking shutter. A wedge20027 is provided on the locking shutter adjacent the free end. The L-shaped arm and wedge define a channel20029. >An inverted U-shaped stop20031 is provided on the body20012 in the interwing region. The stop20031 is accommodated by the channel20029 when the lockingshutter20024 is in the closed condition. In this condition, the resilient nature of the locking shutter brings the wedge20027 into abutment with the stop20031 to maintain the locking shutter in the closed condition. To open the locking shutter, an occlusially directed force is applied to the L-shaped arm to flex the locking shutter and slide the wedge20027 beyond the stop20031 allowing the locking shutter to pivot to the open condition.
• Referring now to FIG. 104, still yet another embodiment of a body for an orthodontic bracket is shown and is generally indicated to by[0231]reference numeral20112. In this embodiment, thebody20112 and mounting pad (not shown) are shaped to deflect food debris and plaque mesially and distally away from the orthodontic bracket in the direction ofarrows20113. Specifically, the gingival surface of the body is rounded and is generally egg-shaped. The occlusal surface of thebody20112 is undulated and has acentral formation20115 thereon defining a pair of curved lateral faces20117. This body design can be used with any of the described orthodontic brackets.
• Referring now to FIGS. 105 and 106, still yet another embodiment of an orthodontic bracket is shown and is generally indicated to by[0232]reference numeral20210. In this embodiment, eachgingival tie wing20216 has a spring-loadedpiston20291 therein. The piston heads20293 extend outwardly of the gingival tie wings into theinterwing region20219 and constitute a retainer for the lockingshutter20224 to maintain the locking shutter in the closed condition. The spring is sealed by astop20225 located on the lateral side of the bracket. Thepistons20291 must be biased into the gingival tie wings in order to pivot the lockingshutter20224 to the open condition. As will be appreciated, similar to the embodiments shown in FIGS.38 to47,97ato97c, and100ato103, the lockingshutter20224 includes a single loop surrounding a pivot pin extending between the occlusal tie wings. Although, the pivot pins are illustrated as extending between the occlusal tie wings, those of skill in the art will appreciate that the pivot pin can extend between the gingival tie wings. It should also be appreciated that the locking shutter may include laterally spaced, single loops to surround the pivot pin or pivot pins at laterally spaced mesial and distal locations.
• If desired, a lubricating or sealing agent can be applied to the body, locking shutter and/or archwire of the previously described orthodontic brackets.[0233]
• The orthodontic brackets described above can be formed of any suitable material such as ceramic, plastic or other cosmetic material. If appropriate, the archwire slot may be constituted by a metallic insert accommodated by the body of the orthodontic bracket. Likewise in the case of the embodiment shown in FIGS. 99[0234]aand99b, the vertical slots accommodating thespring member10732 may also be defined by a metallic inset accommodated by the ceramic body of the orthodontic bracket.
• When the orthodontic brackets are to be used to form braces, it is preferred that pre-engaging twin orthodontic brackets of one of the types illustrated herein be used and attached to the central and lateral teeth and first and second molars and that single orthodontic brackets without wings (not shown) be used and applied to the cuspid and premolar teeth. This system of orthodontic brackets provides advantages in that the nature of the single orthodontic brackets are easier to bond to the posterior crowns of the cuspid and premolar teeth. Also, the single orthodontic brackets provide greater interbracket distances allowing for greater archwire flexibility in the posterior middle regions, cuspids and premolars. Better rotational control is however maintained with the use of the twin preengaging orthodontic brackets on the central and lateral teeth and first and second molars.[0235]
• Although a number of embodiments of orthodontic brackets have been disclosed, those of skill in the art will appreciate that other variations and/or modifications may be made to the present invention without departing from the scope thereof as defined by the appended claims.[0236]

Claims (37)

1. 4. An orthodontic bracket as defined in claim3 wherein said locking shutter is pivotally connected to said body.
2. 5. An orthodontic bracket as defined in claim2 wherein said leaf spring is located on said locking shutter between said gingival and occlusal tie wings.
3. 6. An orthodontic bracket as defined in claim2 wherein said leaf spring extends mesiodistally and is secured to said locking shutter intermediate its ends, said leaf spring having respective mesial and distal formations thereon extending into said archwire slot when said shutter is in a closed position.
4. 7. An orthodontic bracket as defined in claim2 wherein said biasing means is in the from of a resilient spring member secured to said locking shutter, said spring member extending occlusiogingivally.
5. 8. An orthodontic bracket as defined inclaim 7 wherein said spring member includes an outwardly convex portion intermediate its length extending lingually into said archwire slot when said locking shutter is in said closed position.
6. 9. An orthodontic bracket as defined in claim1 wherein said locking shutter is formed of resilient material and is engageable with an archwire in said archwire slot when in said closed position thereby to constitute said biasing means.
7. 10. An orthodontic bracket for attaching an archwire to a tooth comprising:

   a body having a lingual surface for attachment to a tooth, a pair of laterally spaced gingival tie wings and a pair of laterally spaced occlusal tie wings, said gingival and occlusal tie wings projecting from a labial surface of said body, both said gingival tie wings and occlusal tie wings at opposed mesial and distal sides of said body being separated by an interwing region of said body;

   an archwire slot extending mesiodistally across said body and between the gingival and occlusal tie wings at opposed mesial and distal sides of said body to accommodate an archwire, said archwire slot being interrupted by said interwing region;

   a locking shutter movable relative to said body between an open position in which placement and removal of said archwire in said archwire slot is facilitated and a closed position in which placement and removal of said archwire from said archwire slot is inhibited; and

   biasing means engageable with an archwire in said archwire slot when said locking shutter is in said closed position to urge said archwire towards said locking shutter to provide a continuous corrective force thereon.
8. 11. An orthodontic bracket as defined inclaim 10 wherein said biasing means is in the form of a resilient spring member extending mesiodistally along said archwire slot, said spring member being secured to said body and having at least one free end.
9. 12. An orthodontic bracket as defined inclaim 11 wherein said spring member has a central portion secured to said body and labially curved wings at opposed ends of said central portion to contact said archwire and urge resiliently said archwire toward said locking shutter.
10. 13. An orthodontic bracket as defined inclaim 12 wherein the length of said spring member is less than or equal to the length of said archwire slot so that said curved wings contact said archwire within said archwire slot.
11. 14. An orthodontic bracket as defined inclaim 12 wherein the length of said spring member is greater than the length of said archwire slot, said labially curved wings contacting said archwire exterior to said archwire slot.
12. 15. An orthodontic bracket as defined inclaim 11 wherein said spring member is generally convex and is secured to said body adjacent one end thereof.
13. 16. An orthodontic bracket as defined inclaim 15 wherein the length of said spring member is less than or equal to the length of said archwire slot so that said spring member remains in said archwire slot when partially flattened by an archwire in said archwire slot.
14. 17. An orthodontic bracket as defined inclaim 10 wherein said biasing means is in the form of a generally convex resilient spring member secured to said body adjacent one end thereof, said spring member extending occlusiogingivally in said interwing region.
15. 18. An orthodontic bracket as defined inclaim 10 wherein said biasing means includes magnetized elements within said body adjacent to at least a lingual wall of said archwire slot to present a magnetic field in said archwire slot, said archwire being magnetized to the same polarity as said magnetic field so that said magnetic field urges said archwire toward said locking shutter when placed in said archwire slot.
16. 19. An orthodontic bracket as defined inclaim 10 wherein said biasing means is in the form of a pair of spring loaded pistons accommodated by said body adjacent opposed mesial and distal ends of said archwire slot, said spring loaded pistons acting on said archwire to urge said archwire toward said locking shutter.
17. 20. An orthodontic bracket as defined inclaim 19 wherein each of said pistons includes a piston head sized to inhibit said archwire from moving behind said piston head.
18. 21. An orthodontic bracket as defined inclaim 10 wherein said biasing means is in the form of resilient spring members secured to said body and engageable with an archwire passing through said archwire slot at mesial and distal locations exterior to said archwire slot.
19. 22. An orthodontic bracket as defined inclaim 21 wherein said resilient spring members are in the form of labial wings extending from opposed ends of a central strap secured to said body.
20. 23. An orthodontic bracket as defined inclaim 21 wherein each of said spring member is secured to an opposed side of said body and contacts said archwire at a lateral angle greater that.
21. 24. An orthodontic bracket as defined inclaim 17 wherein said spring member is accommodated by a generally vertical slot in said body lingual to said archwire slot, said vertical slot opening up into said archwire slot in said interwing region.
22. 25. A pre-engaging orthodontic bracket for attaching an archwire to a tooth comprising:

    a body having a lingual surface for attachment to a tooth, a pair of laterally spaced gingival tie wings and a pair of laterally spaced occlusal tie wings, said gingival and occlusal tie wings projecting from a labial surface of said body, both said gingival tie wings and occlusal tie wings at opposed mesial and distal sides of said body being separated by an interwing region of said body;

    an archwire slot extending mesiodistally across said body and between the gingival and occlusal tie wings at opposed mesial and distal sides of said body to accommodate an archwire, said archwire slot being interrupted by said interwing region; and

    a locking shutter pivotal about at least one pivot pin between an open position in which placement and removal of said archwire in said archwire slot is facilitated and a closed position in which placement of said archwire in said archwire slot is inhibited.
23. 26. An orthodontic bracket as defined inclaim 25 wherein said pivot pin extends between the tie wings of one of said pair and wherein said locking shutter includes a single loop at one end thereof to surround said pivot pin.
24. 27. An orthodontic bracket as defined inclaim 25 wherein said locking shutter includes a pair of laterally spaced, single loops surrounding said pivot pin.
25. 28. An orthodontic bracket as defined inclaim 25 wherein said locking shutter further includes a marker thereon to identify generally the center of said archwire slot when said locking shutter is in said closed position.
26. 29. An orthodontic bracket as defined inclaim 25 further including a lubricating or sealing agent carried by one or more of said body, locking shutter and archwire.
27. 30. An orthodontic bracket as defined inclaim 25 wherein at least one of said gingival tie wings has at least one groove formed therein.
28. 31. An orthodontic bracket as defined inclaim 25 further including a locking mechanism acting between said body and said locking shutter to maintain said locking shutter in said closed position.
29. 32. An orthodontic bracket as defined inclaim 31 wherein said locking mechanism includes a pair o f sp aced projections extending from said body and an opening in said locking shutter, said projections being flexed together when accommodated by said opening.
30. 33. An orthodontic bracket as defined inclaim 31 wherein said locking mechanism includes a bulbous lip formed on said body, said locking shutter curving lingually and occlusially at its free end to engage said lip when said locking shutter is in said closed position.
31. 34. An orthodontic bracket as defined inclaim 33 wherein said locking shutter curves lingually and occlusially at its free end and wherein said locking mechanism is constituted by co-operating wedge shaped formations on said body and said free end.
32. 35. An orthodontic bracket as defined inclaim 31 wherein said locking mechanism includes a spring member carried by said locking shutter, said spring member acting between said locking shutter and pivot pin to bias said locking shutter into retaining notches formed in the tie wings of one of said pair.
33. 36. An orthodontic bracket as defined inclaim 31 wherein said locking mechanism includes a stop on said body and a wedge on said locking shutter to abut said stop when said locking shutter is compressed and moved to said closed position.
34. 37. An orthodontic bracket as defined inclaim 31 wherein said locking mechanism includes a spring-loaded piston accommodated by a tie wing and extending into said interwing region.
35. 38. A body for an orthodontic bracket having a mesiodistally extending archwire slot formed therein and gingival and occlusal surfaces shaped to deflect food debris and plaque mesially and distally therefrom when secured to a tooth.
36. 39. A body as defined inclaim 38 wherein said gingival surface is generally egg-shaped and wherein said occlusal surface is undulated to present a pair of oppositely directed curved lateral faces.
37. 40. A set of braces including a plurality of orthodontic brackets to be attached to an individual's teeth, said braces including self-engaging twin orthodontic brackets to be attached to the central and lateral teeth and first and second molars of said individual and single orthodontic brackets to be attached to the cuspid and premolar teeth of said individual.

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