Effects of Implanting Torques on Implant Osseointegration in an Animal Model

Abstract

Objective: To investigate the effect of insertion torque on implant osseointegration in an animal model. Methods: First, the first to fourth premolars of nine healthy adult beagles’ mandibular were extracted to form an edentulous area, and then the beagles were equally divided into three groups with different torques (low torque: 10–30 Ncm; medium torque: 30–50 Ncm; high torque: > 70 Ncm). Three implants were placed on each side of the edentulous area of the beagles (54 total), and the dogs were observed for 8 weeks. Implant performance and removal torque values (RTV) were determined at 1, 4, and 8 weeks after surgery. In addition, the expression ratios of OPG and RANKL mRNAs in the surrounding bone tissue were determined. Results: None of the 54 implants showed loosening or loss, and no significant bone resorption was observed. The removing torques and the expression ratios of OPG and RANKL mRNAs showed differences at 1 and 4 weeks after surgery, while they converged at 8 weeks after the surgery (p > 0.05). Conclusion: The osteointegration process lasted approximately 8 weeks depending on the difference in parameters, and all parameters showed the same values even though the insertion torques at the beginning were different.