Association Between Temporomandibular Joint Morphology and Mandibular Growth in Adolescents With Facial Asymmetry: An Magnetic Resonance Imaging and Cone-Beam Computed Tomography Study

OBJECTIVE: To investigate the growth and developmental characteristics of the temporomandibular joint (TMJ) in adolescents with facial asymmetry and its relationship with mandibular morphological changes. METHODS: A total of 20 patients aged 8 to 20 years with facial asymmetry who underwent functional orthodontic treatment were included. MRI and cone-beam computed tomography (CBCT) examinations were performed before treatment and at 1-year follow-up. Measurements were conducted using Dolphin Imaging software. Pearson or Spearman correlation analyses were applied to evaluate associations between craniofacial parameters and mandibular growth changes. RESULTS: No significant correlations were observed between ODI or APDI and mandibular growth parameters (P > 0.05). The upper gonial angle (Ar-Go-Na) was significantly positively correlated with mandibular growth changes (diff_D1d1, diff_D2d2), as well as with articular disc volume and contact area (P < 0.05). Articular disc volume was positively correlated with ipsilateral mandibular growth. No significant difference was found between the deviated side and contralateral side in mandibular growth. CONCLUSION: Mandibular growth is closely associated with the contact area between the TMJ disc and condyle, as well as the upper gonial angle. Orthodontic treatment may promote adaptive remodeling of the TMJ by modifying the biomechanical environment of the mandible, thereby improving facial asymmetry.