Clinical study of stability of micro implant used as orthodontic anchorage

Objective To study the stability of micro implant anchorage after orthodontic force.Methods Totally 26 patients with micro implants as the maxillary anchorage from March 2008 to March 2011 to in our hospital were included in this study.Micro implants were inserted on the maxillary alveolar between the second premolar and the first molar as a direct anchorage for anterior teeth retraction.And at 2 weeks after implant placement,6 months,X ray skull lateral positioning,comparing changes before and after the afterburner,measuring micro-implant shifting.Results After 6 months the horizontal displacement of approximately 0.5mm,the average vertical displacement of approximately 0.4mm,with statistically significant when compared to implants(P0.05),which mini-implant elongation in 7 cases,26.9%.Conclusions Micro implants is a relatively stable anchorage to withstand orthodontic force,the position will be mobile and self-body stretch,so the mini-implant should pay attention to avoid the blood vessels,nerve-rich area,regular follow-up after implantation.