Does TMD Affect Quality of Life in Unexpected Ways?

Temporomandibular disorders (TMD) have been shown to affect oral health related quality of life (OHRQoL) using the Oral Health Impact profile (OHIP). Close examination of data reveals that, for TMD, the responses of individual items on OHIP vary and summary scores indicate a high overall impact. Objectives: To establish whether patients with TMD have impacts on OHRQoL in areas apparently unrelated to the condition itself. Methods: 110 consecutive TMD patients, diagnosed according to Research Diagnostic Criteria, were administered the OHIP questionnaire prior to any clinical intervention, and compared with 110 age and sex matched controls. Individual item scores were compared between the groups using Mann Whitney U Test and prevalence of frequent impacts using Chi Square tests. In addition, raw differences in scores were calculated according to mean, median and prevalence of frequent impacts. Results: 15 items showed consistently very large differences between subjects and controls, all clearly related to TMD and its sequelae. A further 13 items showed differences which were either non significant (p>0.01) or where the actual differences were numerically small and of dubious clinical significance (difference in means of <0.5 OHIP unit, each item can score from 0-4 units). Of the 21 remaining items, all showed statistically significant differences between the patients and controls (p<0.01) which were of clinically significant magnitude (mean score difference 0.66, mean 12% difference in prevalence of frequent impacts). These included items from all domains including various aspects of disability and handicap, but several with no apparent relationship to TMD (e.g. sensitive teeth and perceived bad breath). Conclusion: TMD has a major influence on OHRQoL in many ways, but may affect perceptions of oral impacts distant and sometimes apparently unrelated to the original impairment.