Does the horizontal condylar angle have a relationship to temporomandibular joint osteoarthritis and condylar position? A cone-beam computed tomography study.

Background: The aim of the study was to evaluate the relationship between the horizontal condylar angle (HCA), temporomandibular joint osteoarthritis (TMJ OA), and condylar position on cone-beam computed tomography (CBCT) images.

Materials And Methods: Based on TMJ OA, joints were classified as affected and the unaffected. According to the OA condition of their joints, three groups of patients were formed: control group (n = 159, 41.1%), unilateral group (n = 121, 31.3%), and bilateral group (n = 107, 27.6%). In total, the HCAs of 774 TMJs of 387 patients were measured and their condylar positions were determined as concentric (n = 184, 23.8%), posterior (n = 338, 43.7%), and anterior (n = 252, 32.5%).

Results: The mean HCA of the bilateral group (22.7 ± 7.6°) was greater than those in both the control (19.5 ± 6.4°) and the unilateral (20.5 ± 6.5°) groups (p < 0.05). However, the difference was not statistically significant between the control and unilateral group (p > 0.05). In total patients, unlike the unilateral group, the affected joints had a greater mean HCA than the unaffected joints (p < 0.05). The mean HCAs of the joints according to the condylar position were as concentric: 20.6 ± 6.7°, posterior: 21.1 ± 7.8°, and anterior: 20.2 ± 7.9° (p > 0.05).

Conclusions: While the HCA increased in the presence of TMJ OA, no relationship was found between HCA and three different condylar positions.