This study aimed to compare the fractal dimension values of the mandibular condyle and gonial angle between individuals with and without bruxism using cone-beam computed tomography (CBCT) and to assess the diagnostic performance of fractal analysis.

Forty participants were included, and 160 bilateral regions of interest from the mandibular condyle and gonial angle were analyzed on CBCT images. Fractal dimension analysis was performed for each region of interest (ROI). Data normality was evaluated using the Shapiro–Wilk test. Intergroup comparisons were conducted using the Student’s t -test. Receiver operating characteristic (ROC) analysis was used to assess the diagnostic performance. The correlations between the right and left sides were analyzed using Pearson’s correlation coefficient. Statistical significance was set at P < 0.05.

The mean age of the participants was 40.76 ± 14.71 years. No significant differences in the fractal dimension values were observed between the sexes ( p > 0.05). The fractal dimension values of the mandibular condyle were significantly higher in individuals with bruxism than in controls on both the right ( p = 0.001; Cohen’s d = 1.15) and left sides ( p < 0.001; Cohen’s d = 1.57), indicating large to very large effect sizes. No significant differences were detected in the gonial angle between the groups ( p > 0.05).

CBCT-based fractal dimension analysis appears to be a useful method for evaluating trabecular bone microarchitectural changes associated with bruxism. In individuals with bruxism, the mandibular condyle shows altered trabecular organization, whereas the gonial angle does not demonstrate a comparable pattern of change.