Health risk from occlusal interferences in females.

The purpose of the present study was to test the effect of elimination of occlusal interferences on the incidence of requests for treatment of symptoms in the head and cervicobrachial region. One hundred and twelve females 45 years of age or under, were randomly divided into a treatment group (n = 54) and a control group (n = 58). The former underwent occlusal adjustment and the latter grinding that did not affect occlusal contacts. The treatments were repeated every 12 months over a period of 4 years. The outcome variable was a spontaneous request for treatment. Statistical analyses included chi-square tests for categorical variables and a t- or Wilcoxon ranked sum test for continuous variables. Poisson regression was used to compare the risk of seeking treatment between the groups. The cumulative incidence rate of treatment requests was 2/54 in the treatment group and 11/58 in the control group. The relative risk was 5.12. The 95 per cent confidence limits were 1.14 and 23.1, respectively. The difference between groups was statistically significant (P = 0.0336). Systematic elimination of occlusal interferences significantly reduced the incidence of requests for treatment of symptoms in the head and cervicobrachial region. This is in contrast with the view that there is no, or at best, an insignificant health risk from occlusal interferences.