Targeted Mechanics for Limited Posterior Treatment with Mini-Implant Anchorage

The introduction of temporary anchorage devices (TADs) has facilitated orthodontic management of complex dentofacial problems. TADs have also elicited the creativity of orthodontists in designing new appliances and approaches for treating different malocclusions. One such approach involves delivering orthodontic forces directly from mini-implants in the buccal segments without bonding the posterior teeth. Introduced by Chung and colleagues, this "biocreative therapy" obtains skeletal anchorage from sandblasted and acid-etched miniscrews, called C-implants, which are placed interdentally between the first molars and second premolars. The archwire is inserted in the anterior brackets and secured posteriorly in the slots of the C-implants to retract the anterior teeth during space closure. Because the implants are partially osseointegrated, they can resist these torsional forces without failing. Chung and colleagues have indicated that biocreative therapy was especially appropriate for cases of bimaxillary dentoalveolar protrusion and Class II cases with good buccal occlusion. Advantages of their method include three-dimensional control of the active units, a minimal need for patient compliance, and significantly reduced risks of root resorption or white-spot lesions in the posterior segments.