title: Contributing factors to chronic myofascial pain: a case-control study.
abstract: This case-control study was designed to investigate the contributing factors for chronic masticatory myofascial pain (MFP). Eighty-three patients with MFP, selected from the dental clinics of the Jewish General and Montreal General Hospitals, Montreal, Canada, and 100 concurrent controls selected only at the first clinic, participated in this study. The association with MFP was evaluated for bruxism, head-neck trauma, psychological factors (symptom check list 90 revised questionnaire, SCL-90R) and sociodemographic characteristics by using unconditional logistic regression. Clenching-grinding was associated with chronic MFP in multiple models including anxiety (OR=8.48; 95% CI: 2.85; 25.25) and depression (OR=8.13; 95% CI: 2.76; 23.97). This association also remained for MFP, excluding all other temporomandibular disorders (TMD). Clenching-only (OR=2.54; 95% CI: 1.10; 5.87) and trauma (OR=2.10; 95% CI: 1.0; 4.50) were found to be associated with the chronic MFP, when the level of anxiety was adjusted in the model. No significant change was noted when the effects of clenching-only (2.76; 95% CI: 1.20; 6.35) and trauma (OR=2.08; 95% CI: 1.03; 4.40) were adjusted for depression. Clenching-only and clenching-grinding remained related to MFP regardless of patients being informed about these habits. A higher score of anxiety (OR=5.12; 95% CI: 1.36; 19.41) and depression (OR=3.51; 95% CI: 1.07; 11.54) were associated with MFP, as well as other psychological symptoms. In addition, female gender had almost three times the risk of chronic MFP than males when the model was also adjusted for psychological symptoms. Grinding-only, age, household income and education were not related with chronic MFP. Tooth clenching, trauma and female gender may contribute to MFP even when other psychological symptoms are similar between subjects.
authors.affiliation: Centre for Clinical Epidemiology and Community Studies, Sir Mortimer B. Davis Jewish General Hospital, Room A-132, 3755, chemin de la Côte-Sainte-Catherine, Montreal, Quebec, Canada H3T 1E2 Dental Department, Sir Mortimer B. Davis Jewish General Hospital, Montreal, Quebec, Canada H3T 1E2 Faculty of Dentistry, McGill University, Montreal, Quebec, Canada Département de médecine sociale et préventive, Faculté de médecine, Université de Montréal, CP 6128 Succursale Centre Ville, Montreal, Quebec, Canada H3C 3J7.
authors.forename: Ana M
authors.initials: AM
authors.lastname: Velly
authors.forename: Mervyn
authors.initials: M
authors.lastname: Gornitsky
authors.forename: Pierre
authors.initials: P
authors.lastname: Philippe
mesh_terms: D000293:Adolescent; D000328:Adult; D002012:Bruxism / Q000150:complications / Q000523:psychology; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D002908:Chronic Disease; D016001:Confidence Intervals; D006259:Craniocerebral Trauma / Q000150:complications / Q000523:psychology; D005156:Facial Neuralgia / Q000209:etiology* / Q000523:psychology*; D005260:Female; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D016017:Odds Ratio; D012307:Risk Factors; D012737:Sex Factors