Changes in dental status and prevalence of symptoms related to temporomandibular disorders in 50- to 70-year-old subjects - Longitudinal and cross-sectional results

The aim was to assess changes in prevalence of some reported TMD-related symptoms and dental status in 50-year-old subjects who were followed for 20 years. Identical questionnaires were sent to all subjects born in 1942 and living in two Swedish counties every fifth year, from 1992 to 2012. The response rate varied between 71 to 75%, resulting in five cross-sectional samples varying from 5,697 to 6,513 subjects, and a longitudinal sample of 3,585 subjects participating in all examinations. The great majority (80 to 90%) reported no symptoms related to TMD. Prevalence and symptom severity changed only little over time. Less than 3% considered their TMD symptoms to be severe or rather severe. The mean prevalence of TMD-related symptoms and bruxism was greater in women than in men, whereas gender differences in the number of teeth were extremely small. The longitudinal sample had similar prevalence of TMD-related symptoms and reported bruxism, but had more teeth and better chewing ability than the cross-sectional samples. It was concluded that the prevalence of TMD-related symptoms was low but higher in women than in men, whereas there was no gender difference in dental status. The longitudinal sample had more teeth than the cross-sectional samples but there was no difference regarding TMD-related symptoms. Keywords: bruxism, chewing ability, dental status, epidemiology, questionnaire study