Correlation analysis of articular disc position with condyle position and morphology assisted by fused image

This study aimed to analyze the correlation between disc position and condylar position and morphology through fused cone-beam computed tomography (CBCT) and magnetic resonance (MR) images.

Patients exhibiting temporomandibular disorder symptoms were included, and joints with poor osseous consistency were excluded. Angle of disc was measured in the fused image using the method proposed in this study. Joint spaces were measured, and condylar morphology was assessed in cone-beam computed tomography images. Statistical analysis was performed to examine the reliability of the measurement method and the correlation between disc position and condylar position/morphology. A logistic regression model was used for identifying factors associated with anterior disc displacement.

Our results showed that inter- and intra-observer agreement for measurements of disc angle and joint space were excellent (intraclass correlation coefficient > 0.9). Superior joint space, posterior joint space, and natural logarithm of the posterior-to-anterior joint space ratio showed significant correlations with the angle (P < .01) and significant differences between groups (P < .01). The posterior-to-anterior joint space ratio was significantly smaller in the mild displacement group. The logistic regression model demonstrated that a beak-like shape in oblique sagittal view (OR = 5.235, P < .05) and reduced posterior-to-anterior ratio (OR = 0.301, P < .05) significantly increased the risk of anterior disc displacement.

Condylar position and morphology demonstrated statistically significant association with disc position. Multivariate logistic regression analysis revealed that condylar position and morphology in sagittal views in cone-beam computed tomography images can serve as indicators for disc displacement.