Cortical Bone Strains Around Straight and Angulated Immediate Orthodontic Microimplants: A Pilot Study

Abstract

Purpose: To measure strains around orthodontic implants upon torque tightening and loading and to assess correlations between factors influencing primary stability. Materials and Methods: Self-drilling implants were placed into bovine iliac crest blocks after CT assessments. Upon bonding of strain gauges on bone adjacent to the implants, strain measurements were performed using a data acquisition system during torque tightening and 250 g orthodontic force application by elastic chains. Results: The torque required to place straight implants (12.16 N.cm) was higher than 30- to 40-degree angulated implants (9.31 N.cm) (P < 0.05). Cortical bone strain amplitudes of both implant placements were comparable (P > 0.05). Strains during torque tightening of straight (196 me) and tilted (114 mu is an element of) implants were higher than those obtained during orthodontic loading (20-30 mu is an element of). Despite the positive and direct relationship found between torque and torque strain output, strong correlations between other parameters could not be detected. Conclusion: Vertically aligned and 30- to 40-degree angulated immediate orthodontic microimplants are associated with low amplitude strains upon torque tightening and orthodontic loading. (Implant Dent 2013;22:133-137)