Objectives: The purpose of this study was to determine whether bony changes in temporomandibular joint (TMJ) osteoarthritis (OA) is correlated with pain and other clinical signs and symptoms.
Methods: Clinical data and cone beam CT (CBCT) images of 30 patients with TMJ OA were analysed. The criteria of Koyama et al (Koyama J, Nishiyama H, Hayashi T. Follow-up study of condylar bony changes using helical computed tomography in patients with temporomandibular disorder. Dentomaxillofac Radiol 2007; 36: 472-477.) and Ahmad et al [Ahmad M, Hollender L, Anderson Q, Kartha K, Ohrbach R, Truelove EL, et al. Research diagnostic criteria for temporomandibular disorders (RDC/TMD): development of image analysis criteria and examiner reliability for image analysis. Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2009; 107: 844-860.] were used to classify the condyles observed on the CBCT. Clinical measures included self-reported pain, mandibular range of motion, TMJ sound, pain on palpation of the TMJ and masticatory muscles, and pain on jaw function. Generalized linear modelling was used to correlate the clinical and radiographic findings and Spearman's rho was used to correlate the two classification systems.
Results: There was poor correlation between the maximum condyle change and pain rating (Koyama: r² = 0.1443, p = 0.3995; Ahmad: r² = 0.0273, p = 0.9490), maximum mouth opening (Koyama: r² = 0.2910, p = 0.0629; Ahmad: r² = 0.2626, p = 0.0951), protrusion (Koyama: r² = 0.0875, p = 0.7001; Ahmad: r² = 0.1658, p = 0.3612), right lateral motion (Koyama: r² = 0.0394, p = 0.9093; Ahmad: r² = 0.0866, p = 0.6877) and left lateral motion (Koyama: r² = 0.0943, p = 0.6494; Ahmad: r² = 0.1704, p = 0.3236). Strong correlation was observed between Koyama et al's and Ahmad et al's classifications for average (r = 0.9216, p < 0.001) and maximum (r = 0.7694; p < 0.0001) bony change.
Conclusions: There was poor correlation between condylar changes (as observed on CBCT images), pain and other clinical signs and symptoms in TMJ OA.