Temporomandibular joint disorders' impact on pain,function,and disability

The aim of this study was to determine the association between more advanced stages of temporomandibular joint (tmj) intra-articular disorders (tmj intra-articular status),representing a transition from normal joint structure to tmj disc displacement with and without reduction (ddwr and ddwor) to degenerative joint disease (djd),and patient-reported outcomes of jaw pain,function,and disability (tmd impact). this cross-sectional study included 614 cases from the rdc/tmd validation project with at least one temporomandibular disorder (tmd) diagnosis. tmj intra-articular status was determined by 3 blinded,calibrated radiologists using magnetic resonance imaging and computed tomography as one of normal joint structure,ddwr,ddwor,or djd,representing the subject's most advanced tmj diagnosis. tmd impact was conceptualized as a latent variable consisting of 1) pain intensity (characteristic pain index from the graded chronic pain scale [gcps]),2) jaw function (jaw functional limitation scale),and 3) disability (disability points from gcps). a structural equation model estimated the association of tmj intra-articular status with the latent measure tmd impact as a correlation coefficient in all tmd cases (n = 614) and in cases with a tmd pain diagnosis (n = 500). the correlations between tmj intra-articular status and tmd impact were 0.05 (95% confidence interval [ci],-0.04 to 0.13) for all tmd cases and 0.07 (95% ci,-0.04 to 0.17) for cases with a pain diagnosis,which are neither statistically significant nor clinically relevant. conceptualizing worsening of tmj intra-articular disorders as 4 stages and characterizing impact from tmd as a composite of jaw pain,function,and disability,this cross-sectional study found no clinically significant association. models of tmj intra-articular status other than ours (normal structure → ddwr → ddwor → djd) should be explored. © international & american associations for dental research.