Abstract: An orthodontic bracket is capable of smoothly performing an orthodontic operation without the need of any troublesome fastening operation, and securely fixes an orthodontic wire in slots by pressing the wire with a suitable magnitude of elastic force. The bracket includes a bracket body and a pressing spring. The bracket body has mounts provided on a base with a predetermined spacing therebetween in a facing fashion and also provided in the middle with slots. The bases of the mounts are formed with axial holes. Further, the pressing spring includes a pressing portion, which is provided at a central portion of the wire and has a length bridging the slots, and which is bent at both ends thereof in the same direction to bridge the slots. A pair to upright portions is formed at tip ends of the pressing portion to rise upright along outer sides of the slots. A pair of axial support portions is formed at tip ends of the upright portions to extend through the axial holes.

Abstract: A lock for orthodontic treatment comprises a holding member fixed to a molar band, and a spring wire having an end removably held by the holding member. The holding member is configured such that the end of the spring wire is held on the holding member by being moved axially along the holding member. One of the holding member and the spring wire has elasticity in a direction perpendicular to its axis. The holding member includes a first engagement portion for preventing the movement of the end of the spring wire in a mounting direction, and a second engagement portion for preventing the movement of the end of the spring wire in a removing direction. The spring wire includes a first locking portion for engaging with the first engagement portion of the holding member, and a second locking portion for engaging with the second engagement portion of the holding member.

Abstract: A twister for orthodontic ligature wires which easily enable a twisting operation of the wire with one hand, and is capable of clamping the wire with certainty, and simple in construction. The twister for passing the ligature wire in a nipping cylinder and a gripping cylinder to nip the wire, comprises a guide hole provided in the nipping cylinder to enable inserting the wire in a direction along a central axis of the nipping cylinder, an insertion port provided at a tip end of the guide hole, a compartment pin for inhibition of twisting provided on the insertion port, or an engagement piece provided on an extension of the insertion port, and a locking mechanism mounted in the nipping cylinder and the gripping cylinder to allow engagement and disengagement of the wire with one hand.

Abstract: An orthodontic bracket with reinforced retentive forces is provided by forming, in the undersurface of the bracket, a plurality of fine grooves in one direction and a plurality of fine grooves in the other direction crossing the first-mentioned direction. These fine grooves are formed by a cutting machine having a plurality of rotatable thin circular cutter blades. The grooves are of relatively deep square or rectangular cross section and capable of firmly retain relatively large quantity of adhesives. The bracket of the invention, when bonded to the tooth surface by the use of adhesives, is not subject to separation of adhesives from the metal surface.