LAUSR

PURPOSE To evaluate the position and bilateral difference of mandibular ramus region, specifically the condyle, sigmoid notch, and mandibular angle in skeletal class III patients with mandibular asymmetry. MATERIALS AND METHODS 3D-CT images were performed in 50 patients with skeletal class III malocclusion. According to the severity of mandibular asymmetry, 22 cases were included in the control group and 28 cases were included in the symmetry group. The 3D landmarks were measured relative to 6 reference planes and the outcomes among different groups were compared. RESULTS There are significant differences in the position of mandibular ramus region between both sides in the asymmetry group. The position of condyle was more posterior and internal on the deviated side; and the positions of sigmoid notch and gonion were more posterior, superior, and lateral on the deviated side. Furthermore, the degree of mandibular asymmetry was more highly correlated with the height of ramus and the position of mandibular angle than it was with the height of condyle and the position of sigmoid notch. CONCLUSION When evaluating mandibular asymmetry and making surgical plans, the position of mandibular ramus should be taken into consideration.