A New Approach to Prevent Migration of Mini-Implants

Abstract

Aim:The aims of this study were to determine the amount of mini-implant deflection under orthodontic loading and examine the effectiveness of a newly designed ring (mini-implant ring - MIR) placed at the collar of mini-implants.Materials and Methods:A total of 48 mini-implants were applied to the bone samples obtained from the ileum of bovine. In the study group 24 mini-implants were applied with MIR and remaining mini-implants were applied without MIR and were assigned as control. All mini-implants were subjected to a tangential force load of 200 g perpendicular to the screw, and displacement of screws was measured in millimeters by an Instron Universal Testing machine. After loading test, each mini-implant was removed, and the cortical bone thicknesses of the samples were measured. According to the cortical thickness of the samples, study and control groups were sub-grouped as having thin and thick cortical bone.Results:The mean displacement values of mini-implants inserted with MIR was significantly lower when compared with that of mini-implants inserted without MIR under 200 g force (p0.05).Conclusion:MIR might be a useful auxiliary to mini-implants especially in patients with thin cortical bone.

Keywords

• mini-implant
• stability
• displacement
• mini-implant ring