Temporomandibular Myofascial Pain With Referral Is Associated With Widespread Pain

Objectives: The first aim was to evaluate the association between myofascial pain with referral according to the Diagnostic Criteria of Temporomandibular Disorders (DC/TMD) and widespread pain in the general population. Our second aim was to evaluate the prevalence of, and factors associated with widespread pain.
Methods: This study was undertaken at the Public Dental services in Västerbotten, Sweden, during 2014 and 2015. Individuals with and without symptoms indicative of TMD were randomly invited, based on their answers to three validated screening questions for TMD (3Q/TMD). In total, 300 adult individuals (202 women, 20-69 yrs) were included. All individuals underwent a clinical examination according to the DC/TMD and completed a pain drawing. The widespread pain index was used to characterize individuals with widespread pain (WSP) and considered positive when an individual reported ≥7 pain sites. The population based, weighted prevalence of WSP was calculated based on a normative prevalence of 4.8% 3Q-positives, among 20-69 year-olds, during 2014 and 2015. Logistic regression analysis was used to evaluate associations.
Results: The weighted prevalence of widespread pain in this general population sample was 15%. In a univariate analysis of examination variables, widespread pain was associated to myalgia (OR 2.80; 95% CI 1.61-4.86) and to myofascial pain with referral (OR 7.49; 95% CI 3.44-16.34). In a multivariate model, widespread pain was associated to frequent orofacial pain (OR 6.03; 95% CI 2.67-13.61) and to female gender (OR 2.06; 95% CI 1.06-4.01).
Conclusions: In conclusion, generalized pain was associated with orofacial pain and female gender. In addition, myofascial pain with referral according to the DC/TMD is associated with a generalized pain condition, which points towards possible central sensitization and hyperalgesia.