A study of teeth contacting habit of TMD patients

OBJECTIVE: Some TMD patients were usually touching their teeth in life. We called this parafunction teeth contacting habit(TCH)and suspected it a perpetuating factor for maintaining symptoms. The objective was to investigate the associating factors for TMD patients with TCH. We had two hypotheses: 1) TCH maintains the TMD pain; 2) TCH is related to the other contributing factors. METHODS: The hypothesis 1) were verified with multiple stepwise logistic regression analysis on 167 subjects whose pain had been lasting for over four months before their visit to the clinic. These subjects were divided into two groups by whether their pain improved or not at the first visit. The analysis was carried out with this improve/not-improve as a dependent variable, and with sex, age, diagnostic subtype, score of Hospital Anxiety and Depression scale, score of Eysenck Personality Questionnaire Short Form, and binary score of 10 oral parafunctional factors, 16 usual behavioral factors and 8 working environmental factors as independent variables. As for hypothesis 2), the analysis was carried out with the presence/absence of TCH as a dependent variables, and above-mentioned items as independent variables. RESULTS: The TCH was considered to be a significant contributing factor for pain lasting for over four months (OR: 2.402, 95%CI: 1.199-4.811). The analysis for hypothesis 2) showed that the significant associating factors with TCH included higher neuroticism score over 20 out of 24 (OR: 1.258, 95%CI: 1.013-1.562), unilateral chewing (OR: 1.777, 95%CI: 1.139-2.773), being in a precision work (OR: 1.680, 95%CI: 1.032-2.734), self-awareness of bruxism (OR: 1.946, 95%CI: 1.256-3.016). CONCLUSION: These results suggested that the diurnal TCH might be a perpetuating factor, and this parafunctional behavior related to personal trait and several behavioral factors.