An orthodontic bracket for coupling an archwire with a tooth. The
orthodontic bracket comprising a ceramic injection molded (CIM) bracket
body including an archwire slot that is configured to receive the
archwire therein. The CIM bracket body comprising a polycrystalline
ceramic. A coating of alumina or silicon dioxide is in continuous and
direct contact with at least the surfaces of the archwire slot. The
orthodontic bracket is characterized by unexpectedly high torque
strength. The ceramic injection molded (CIM) bracket body may comprise a
polycrystalline ceramic having a grain size distribution characterized by
an average grain size in the range of larger than 3.4 .mu.m to about 6
.mu.m such that the orthodontic bracket is also characterized by
unexpectedly high fracture toughness. A method of making the orthodontic
bracket comprises injection molding a bracket using a ceramic powder,
sintering the molded bracket, and coating the ceramic injection molded
bracket.