Relationship between temporomandibular disorders, widespread palpation tenderness, and multiple pain conditions: a case-control study.

UNLABELLED: The multiple bodily pain conditions in temporomandibular disorders (TMD) have been associated with generalized alterations in pain processing. The purpose of this study was to examine the relationship between the presence of widespread body palpation tenderness (WPT) and the likelihood of multiple comorbid pain conditions in TMD patients and controls. This case-control study was conducted in 76 TMD subjects with WPT, 83 TMD subjects without WPT, and 181 non-TMD matched control subjects. The study population was also characterized for clinical pain, experimental pain sensitivity, and related psychological phenotypes. Results showed that: 1) TMD subjects reported an average of 1.7 comorbid pain conditions compared to .3 reported by the control subjects (P < .001); 2) Compared to control subjects, the odds ratio (OR) for multiple comorbid pain conditions is higher for TMD subjects with WPT [OR 8.4 (95% CI 3.1-22.8) for TMD with WPT versus OR 3.3 (95% CI 1.3-8.4) for TMD without WPT]; 3) TMD subjects with WPT presented with reduced pressure pain thresholds (PPTs) in both cranial and extracranial regions compared to TMD subjects without WPT; and 4) TMD subjects with WPT reported increased somatic symptoms. These findings suggest that pain assessment outside of the orofacial region may prove valuable for the classification, diagnosis, and management of TMD patients. PERSPECTIVE: TMD subjects with WPT experience a greater level of multiple comorbid pain conditions, compared to TMD subjects without WPT and non-TMD controls. Integration of bodily pain assessments can be informative for evaluation, diagnosis, and management of TMD.