Association of bite force with ageing and occlusal support in older adults

OBJECTIVES: The purpose of this study was to investigate the effect of ageing, occlusal support and TMJ condition and general health status on bite force in older adults. METHODS: The study sample consisted of 850 independently-living people over the age of 60 years. Bilateral maximal bite force in the intercuspal position was measured with pressure sensitive sheets. TMJ noise by palpation and limitation of mouth opening (less than 40 mm) were assessed. Subjects were grouped into three categories by occlusal support according to the Eichner Index. RESULTS: A multiple logistic regression analysis showed that whether participants had low bite force or not was significantly associated with gender, age, self-rated general health and occlusal support, but not TMJ noise or mouth opening limitation. Overall bite force showed a statistically significant but weak negative Spearman's correlation with age (r=-0.24, p<0.001). However, there was no significant correlation between age and bite force in the Eichner C group for males or in any of the Eichner classification for females. CONCLUSIONS: Decline of occlusal support and general health might translate into reduction of bite force with ageing in older adults. Since tooth loss is not physiological ageing but pathological ageing, it cannot be shown that reduction of bite force is a natural effect of ageing.