Relationship between increased horizontal condylar angle and resorption of the posterosuperior region of the lateral pole of the mandibular condyle in temporomandibular joint internal derangement

Objectives: The purpose of this study was to analyse the relationship between horizontal condylar angle, temporomandibular joint (TMJ) disk displacement and resorption of the lateral pole of the mandibular condyle (RLC). Methods: The study comprised 162 TMJs (81 patients). Disk displacement was assessed and the horizontal angle of the condyle was measured on axial MR images. RLC was assessed on oblique frontal projection plain radiographs. Results: The horizontal angle was increased in joints with disk displacement without reduction (one-factor ANOVA and Scheffe's f-test, P < 0.05). The angle was greater in joints with RLC than in the joints without RLC (Student's t-test, P < 0.05). Conclusions: Results suggest that the horizontal condylar angle is increased in joints with disk displacement without reduction. A possible relationship exists between RLC and increased horizontal condylar angle.