Self-ligating orthodontic bracket
The present disclosure provides high strength, self-ligating appliances with orthodontically desirable dimensions. The appliances of the present disclosure incorporate a door slidably engaged to a channel in the body; one that can be opened or closed depending on the equilibrium position of an integral protrusion on the door. Cooperating grooves and rails on the body and the door can guide the door between the open and closed positions, and mitigate against unintentional detachment.
1. An orthodontic appliance comprising:
a base having a bonding surface,
a body extending outwardly from the base, the body including a mesial-distally extending archwire slot having a bottom wall and a channel in the body oriented generally perpendicular to the archwire slot and having a bottom wall,
a deflectable beam extending in a mesial-distal direction across the channel;
a door slidably coupled to the body and including a lingual surface opposing a facial surface, the door moveable between an open state in which an archwire can be ligated in the archwire slot and a closed state in which an archwire can be retained in the archwire slot, wherein the lingual surface of the door includes a leading edge region having a contact surface substantially parallel to the bottom wall of the archwire slot in the closed state and a strut slidably received in the channel and extending towards the bottom wall of the channel from a mesial-distal center of the lingual surface of the door, the strut including a protrusion that extends outwardly from a lingual portion of the strut in a generally lingual direction whereby the protrusion deflects the beam toward the bottom wall of the channel as the door transitions from the open state to the closed state,
wherein the leading edge region includes a pair of coplanar contacting surfaces that, when the door is closed, are positioned on opposing mesial and distal ends of the archwire slot, and wherein the height of the archwire slot, when the door is closed, is reduced at the mesial and distal ends compared to regions of the slot adjacent the mesial-distal center.
2. The orthodontic appliance of claim 1 , wherein the body further includes first and second guiderails disposed along opposing sides of the channel.
3. The orthodontic appliance of claim 2 , wherein the lingual surface of the door includes first and second grooves extending through at least a portion of the occlusal-gingival height of the door, and wherein the first guiderail is received in the first groove and the second guiderail is received in the second groove.
4. The orthodontic appliance of claim 3 , wherein the first and second grooves are disposed on opposing sides of the strut.
5. The orthodontic appliance of claim 3 , wherein the door includes a mesial glide region extending in a mesial direction from the first groove and a distal glide region extending in a distal direction from the second groove, the mesial and distal glide regions being generally coplanar.
6. The orthodontic appliance of claim 5 , wherein the leading edge region includes a pair of coplanar contacting surfaces that, when the door is closed, are positioned on opposing mesial and distal ends of the archwire slot, and wherein the glide regions are oriented at an oblique angle relative to the contacting surfaces.
7. The orthodontic appliance of claim 1 , wherein the lingual portion of the strut includes a first concave depression adjacent the protrusion.
8. The orthodontic appliance of claim 7 , wherein the strut includes a leading edge extending to a lingual strut surface adjacent to the bottom wall of the channel.
9. The orthodontic appliance of claim 8 , wherein the protrusion and a wall section of the leading edge of the strut cooperate to hold the deflectable beam captive within the first depression when the door is in the open state.
10. The orthodontic appliance of claim 9 , wherein the deflectable beam is deflectable in directions toward the bottom of the channel to allow the door to transition between the open state and the closed state.
11. The orthodontic appliance of claim 1 , wherein the strut includes at least one rail extending along a side thereof, and wherein the rail is received in a recess in communication with the body channel.
12. The orthodontic appliance of claim 1 , wherein the strut includes a pair of generally concave depressions spaced apart from each other along the direction of travel of the door between a leading edge projection and a trailing edge projection, wherein the protrusion is disposed between the depressions.