Dental compensations with changes in skeletal transverse dimensions: myth or reality

Abstract

Background: Orthodontic treatment aims to harmonize functional and aesthetic aspects of the dentofacial complex, with emphasis on molar inclinations and maxillary transverse dimensions. These parameters, evaluated across sagittal, vertical, and transverse planes, are essential for accurate diagnosis and treatment planning to achieve stable occlusion. This study assessed the correlation between maxillary and mandibular molar inclinations and skeletal transverse dimensions in a mixed Indian population using cone beam computed tomography (CBCT) analysis. Methods: A retrospective, cross-sectional study was conducted on 50 pre-treatment CBCT scans (27 males, 23 females; mean age 19.8 years). Molar inclinations and transverse skeletal dimensions were measured using NNT software. Pearson’s correlation coefficient was applied to evaluate relationships between variables.   Results: The mean mandibular transverse dimension (62.00±6.94 mm) exceeded the maxillary transverse dimension (60.61±4.29 mm). Mean inclinations of the right and left maxillary first molars with the occlusal plane were 79.49°±4.69° and 81.44°±5.71°, respectively, while mandibular first molars showed 106.47°±16.08° (right) and 103.26°±6.20° (left). A significant positive correlation existed between maxillary and mandibular transverse dimensions (r=0.40, p=0.003). The mandibular transverse dimension showed significant negative correlations with right (r=-0.53, p=0.00) and left (r=-0.42, p=0.02) maxillary molar inclinations. Other correlations were non-significant. Conclusions: Findings indicate a significant relationship between mandibular transverse dimension and maxillary molar inclination. While maxillary molar inclination showed weak correlation with skeletal transverse dimensions, the results highlight the importance of considering transverse skeletal parameters in orthodontic diagnosis and treatment planning.