Análise biomecânica de miniparafusos ortodônticos submetidos a múltiplas inserções e esterilização física

Abstract

Introduction: Anchorage control is crucial in orthodontics, so the use of auxiliary devices is necessary for treatment. Orthodontic tooth movement occurs through forces that cause action and reaction. Various devices are available to reinforce anchorage, but they do not eliminate the reaction caused by movement. Temporary anchorage devices, supported by a fixed point, eliminate the reaction effect caused by orthodontic movement. An excellent option is the orthodontic miniscrew, as it is easy to install and can be placed in various locations. Due to its low osseointegration, stability occurs through mechanical retention, so the main concern is the possibility of fracture. Objective: To evaluate the maximum insertion and removal torque of orthodontic miniscrews subjected to physical sterilization. Methodology: This study used 40 miniscrews, distributed into four groups (n=10), divided by the number of reuses and sterilizations. The miniscrews were inserted into a test specimen, then removed, sterilized, and reinserted to assess their resistance to insertion and removal torque. Torque was measured using a digital torque meter. Results: A statistically significant decrease in maximum insertion torque was observed, while maximum removal torque varied between the torque averages at the various times they were removed. However, a statistically significant decrease was observed between removals. The groups showed no statistical difference when evaluated at the same insertion and removal times, revealing homogeneity of the data.