Effect of a miniscrew surgical guide on the success rate and root proximity of orthodontic miniscrews: A retrospective cohort study

Abstract

Objective: To assess the success rate and proximity of miniscrews to the root using surgical guides produced by integrating data obtained from cone-beam computed tomography and intraoral scanned models.

Methods: This retrospective study involved 113 patients (224 miniscrews) who underwent miniscrew placement as part of their orthodontic treatment. Two operators placed miniscrews between the buccal alveolar bone of each patient and assessed initial stability by measuring the Periotest value (PTV) and insertion torque (IT). Patients were divided into two groups based on the miniscrew insertion method: manual group (MG) and surgical guide group (SG). Root proximity was assessed using periapical radiography, and miniscrews that remained in place for over 6 months were considered successful.

Results: There was a statistically significant difference in the Kaplan-Meier survival curves between the groups (P < 0.05). The success rates of the miniscrews were 79.1% and 90.5% for the MG and SG, respectively (P < 0.05). The root contact rate also differed significantly between the groups (MG, 17.5%; SG, 0.1%; P < 0.001). However, the PTV and IT did not show significant differences between the groups.

Conclusions: Proximity to the root and utilization of surgical guides have the most direct impact on the success rate of miniscrews. Root proximity can be effectively reduced using surgical guides. Therefore, the use of a miniscrew surgical guide is recommended to increase the success rate of miniscrews as stable anchorage devices, particularly in cases with narrow interradicular space.