CBCT-based osseous severity is associated with lower mandibular ramus height but not symptom burden in pediatric and adolescent TMJ degenerative joint disease

Background: In pediatric and adolescent temporomandibular joint (TMJ) degenerative joint disease (DJD), subjective symptoms may not reliably reflect imaging-defined structural involvement. This study examined whether cone-beam computed tomography (CBCT)-based osseous severity burden is associated with reduced mandibular ramus height (Co-Go) and whether pain, functional, and psychosocial measures are associated with CBCT-based osseous severity burden. Methods: This retrospective cross-sectional study included 83 patients aged 6–18 years with CBCT-confirmed unilateral or bilateral TMJ DJD. Right- and left-side osseous severity scores were summed to calculate a cumulative bilateral severity burden. Cephalometric, TMJ morphometric, clinical, functional, and psychosocial variables were analyzed using correlation and age- and sex-adjusted regression models. Sensitivity analyses additionally adjusted for the A point-nasion-B-point (ANB) angle and the Frankfort mandibular plane angle (FMA). Results: Higher CBCT-based DJD severity burden was inversely associated with right, left, and mean Co-Go ramus height. In the age- and sex-adjusted model, each one-point increase in severity burden was associated with a 1.209-mm lower mean Co-Go ramus height (95% confidence interval, −1.979 to −0.439; p = 0.0025). After additional adjustment for the ANB angle and FMA, the association was attenuated but remained nominally significant (B = −0.639 mm; 95% confidence interval, −1.261 to −0.017; p = 0.0442). Pain intensity, jaw functional limitation, perceived stress, somatic symptoms, depression, and anxiety were not significantly associated with CBCT-based osseous severity burden. Conclusions: Within this cohort, greater cumulative CBCT-based osseous severity burden was associated with lower Co-Go ramus height. Because Co-Go includes the condylar region, this finding should be interpreted as a structural association within the condyle-ramus unit rather than evidence of impaired mandibular growth. Symptom burden did not consistently correspond to imaging-defined structural involvement, supporting the complementary interpretation of clinical and imaging findings.