Evaluation of mandibular osseous structure in patients with mandibular asymmetry: a fractal analysis study

Abstract

We evaluated the effect of mandibular asymmetry on the trabecular structure of the mandible as measured through fractal analysis (FA). We divided a sample of 105 patients with skeletal class I occlusion, cervical vertebral maturation CS6, and skeletal vertical dimension ratios within normal limits into right asymmetric, left asymmetric, and symmetric groups. We performed FA on 6 bilateral regions of interest on panoramic radiographs of the patients and calculated the mean fractal dimension (FD) for each region. We performed the Wilcoxon signed-rank and paired t tests to compare the significance of differences in FD between sides within each group and between groups for all regions. Statistical significance was established at P < .05. We found statistically significant differences in mean FD values between the right and left condyles of the 2 asymmetric patient groups. The FD was greater in the left condyle of patients with right asymmetry and in the right condyle of patients with left asymmetry. The right condyle had a significantly greater FD in left asymmetric patients than in right asymmetric patients. The results of FA indicate that asymmetry is characterized by an increase in the mean FD of the condyle that is responsible for the asymmetry. Fractal analysis can be a valuable diagnostic technique in distinguishing trabecular differences in the condylar areas of asymmetric individuals.