Comparison of dentoalveolar changes and efficiency of Class II treatment with two premolar extractions or direct Skeletally anchored distalization

Abstract

Many treatment protocols are available for the treatment of Class II malocclusion. Among them, the extraction of 2 maxillary premolars or the use of intraoral destabilizers associated with skeletal anchorage present satisfactory results. However, there is no evidence comparing the dentoalveolar effects and the efficiency of both treatment protocols to improve clinical decision making. Objectives: Therefore, this study aims to compare the dentoalveolar changes and the efficiency of the treatment of Class II malocclusion with the extraction of two premolars and distalization with direct skeletal anchorage, using digitized models.Material and Methods: The retrospective sample will consist of 86 digitized models of 43 patients, divided into two groups. Group 1 (G1) will consist of 50 digitized models of 25 Class II patients treated with extractions of the upper two first premolars. Group 2 (G2) group will consist of 36 digitized models of 18 Class II patients treated with maxillary molar distalization using a cantilever destabilizer anchored to mini-implants. Plaster models at the beginning (T0) and after orthodontic treatment (T1) will be scanned by the 3Shape R700 scanner and analyzed by OrthoAnalyzerTM software. Variables related to sagittal, rotational and transverse dentoalveolar changes will be evaluated with the aid of the software, and the efficiency of each protocol will be estimated by the Treatment Efficiency Index (TEI). Finally, the results obtained will be statistically compared by Student's t-tests, in the presence of normality, or by Mann-Whitney tests in case of its absence.