Effect of micro-osteoperforations on orthodontic tooth movement with clear aligner treatment

Objectives: The objective of this study was to investigate the effect of minimally invasive corticotomy (micro-osteoperforation [MOP]) on the acceleration of tooth movement using clear aligners. Materials and methods: A sample of 46 patients who completed clear aligner treatment with a 3-day change of aligner and the MOP technique was compared to a control group consisting of 59 patients treated with the ordinary 14-day change of aligner. Three-dimensional models were registered to calculate linear and angular changes of teeth to evaluate the accuracy of orthodontic tooth movement, the differential effect of MOPs on gender, age, severity of the malalignment, and the likelihood of refinement treatment. CloudCompare software was used for image registration of the post-treatment/prediction scans to the pretreatment scans, and to measure the actual and predicted amount of displacement of each anterior tooth of both arches. Using the transformation matrices from toothto- tooth alignment, linear and angular displacements in three different planes were obtained and the linear discrepancy and the relative errors for the angular discrepancy were calculated. Results: Statistical analyses showed no significant difference between the experimental and control groups for the accuracy of anterior tooth movement, and the type of movement was unaffected using MOPs. No clinically significant differences were found between the predicted and the actual outcomes of aligner treatment for variables gender, age, and severity of malalignment. However, the frequency of refinement treatment was greater in the 3-day aligner change group with MOPs than in the 14-day change group. Conclusions: Compared to the 14-day change of aligner, the 3-day change of aligner with MOPs did not affect the accuracy of orthodontic tooth movement, suggesting that MOPs can be used to reduce the length of clear aligner treatment without compromising the quality of the clinical outcome. A higher frequency of refinement treatment may be necessary for more complex cases with increased number of aligners and crowding of anterior teeth. Schlagwörter: accelerated tooth movement, clear aligner treatment, micro-osteoperforations, traction of clear aligners