Relationship between temporomandibular joint pain and magnetic resonance imaging findings of internal derangement.

In terms of clinical decision-making in instances of temporomandibular disorders (TMD) and orofacial pain, there is controversy in the literature over the diagnostic significance of the temporomandibular joint (TMJ)-related variable disk-condyle relationship (DCR). The purpose of this study was to investigate whether in patients with TMJ-related pain, the variable of TMJ pain may be linked to magnetic resonance (MR) imaging findings of internal derangement (ID). The study comprised 163 consecutive TMJ pain patients. Criteria for including a patient were report of orofacial pain referred to the TMJ, and the presence of uni- or bilateral TMJ pain during palpation, during function, and/or during unassisted or assisted mandibular opening. Bilateral sagittal and coronal MR images were obtained to establish the prevalence of TMJ ID types. Analysis of the data revealed the presence of TMJ pain to be associated with significantly more MR imaging diagnoses of ID than an absence of ID (P<0.001), and disk displacement without reduction than disk displacement with reduction (P<0.001). Using chi-square analysis, the results showed a significant relationship between the presence of TMJ-related pain and the MR imaging diagnosis of TMJ ID (P=0.001), and TMJ ID type (P=0.000). Use of the Kappa statistical test indicated poor diagnostic agreement between the presence of TMJ pain and the MR imaging diagnosis of ID (K=0.16). The results suggest that the clinical variable of TMJ pain may have a significant effect on the prevalences of MR imaging diagnoses of TMJ ID. The data confirm the biological concept of DCR as a diagnostic approach in patients with signs and symptoms of TMJ-related pain.