Distal Movement of Maxillary Molars Using Miniscrew Anchorage in the Buccal Interradicular Region

Objective: To quantify the treatment effects of interradicular miniscrew anchorage and to confirm the validity of the clinical usage of interradicular miniscrews in the distal movement of maxillary molars in nonextraction treatment. Materials and Methods: Twenty-four maxillary molars were moved to the distal using miniscrews placed in the interradicular space between the second premolar and the first molar at an oblique angle of 20 to 30 degrees to the long axis of the proximal tooth. The teeth were evaluated as to how the molars were moved to the distal with the use of lateral cephalograms and dental casts. Results: Maxillary molars were moved to the distal by 2.8 mm with distal tipping of 4.8 degrees and intruded by 0.6 mm. Maxillary incisors were moved to the distal by 2.7 mm with palatal tipping of 4.3 degrees. Molar extrusion and/or consequent mandibular rotation was not observed in any patient. Conclusion: Miniscrews placed in the maxillary interradicular space provide successful molar distal movement of 2.8 mm without patient compliance and with no undesirable side effects such as incisor proclination, clockwise mandibular rotation, or root resorption. (Angle Orthod. 2009;79: 78-84.)