A Retrospective CBCT Study of the Relationship between Mandibular Symphysis Bone Density and Mandibular Growth Direction.

OBJECTIVE The objective of this retrospective study was to investigate the relationship between mandibular symphysis bone density (BD) and mandibular growth direction in adolescent patients by facilitating the measurement of cortical and cancellous BDs at the mandibular symphysis using cone beam computed tomography (CBCT). STUDY DESIGN 224 adolescent patients (98 males and 126 females) were categorized by sex, age, and mandibular growth direction. Cortical and cancellous BDs were measured along with a sagittal slice at multiple locations. RESULTS Females exhibited higher cortical BD than males at menton (Me, P =0.002). Patients with a posterior growth direction exhibited a higher cortical BD than those with anterior and normal growth direction at Me (P <0.021, P <0.001, respectively), pogonion (Pog, P =0.037, P =0.037, respectively) and genion (Ge, P =0.007, P =0.008, respectively). Patients with a posterior growth direction exhibited a higher cortical BD than those with anterior growth direction at B point (P =0.009). CONCLUSIONS Significant differences in BD were identified across anthropometric categories. These findings may be useful in determining mandibular growth direction in adolescents.