Stability and safety of mini-screw implant anchorage in the oral orthodontics

Objective: To investigate the stability and safety of the mini-screw implant anchorage in oral orthodontics. Methods: In this study, we retrospectively reviewed the clinical data of 120 patients who received the oral orthodontics. Among all these patients, 63 patients who implemented the surgery of the mini-screw implant anchorage were enrolled into the experimental group, and 57 patients who received the enhanced headgear anchorage into the control group. We observed the efficacy of dental orthodontics, complete closure time of the extraction space, inclination angle of the upper central incisor, convexity of the upper central incisor, displacement of the molar, bite force, chewing efficiency and the incidence of adverse reactions. Results: For all patients, the orthodontic success rate in the experimental group was significantly higher than that in the control group (chi(2)=5.844, P=0.018); patients in the experimental group also suffered less due to the significantly shortened complete closure time of the extraction space in comparison with the control group (t=14.110, P < 0.001). Following treatment, the angle of inclination and the convexity of the upper central incisor in the experimental group were much larger than those in the control group (t=15.570 or 13.470, P < 0.001); but the recovery in the biting force and the chewing efficiency in the experimental group was superior to that in the control group (t=15.570, P < 0.001); while the incidence rate of the adverse reactions in the experimental group was significantly lower than that in the control group (chi(2)=8.952, P=0.005). Conclusion: In comparison with the traditional orthodontics, mini-screw implant anchorage can increase the success rate and efficacy of oral orthodontics, with shorter complete closing time of extraction space, lower incidence rate of the postoperative adverse reactions and promising stability and safety.