Edentulousness and its rehabilitation over a 10-year period in a Finnish urban area.

In 1977 78, a baseline study group of 449 Finnish adults aged 30 years and over was examined in an urban area with a very high supply of dental services. The follow-up study in 1988 represents longitudinal data on 297 of these adults. In 1989 a new sample of persons aged 30-39 years was also obtained to provide cross-sectional information comparable to that of the corresponding age group in the 1977-78 survey. At baseline in 1977-78, the prevalence of total tooth loss was 19.4% for adults aged 30 years and over. The corresponding figures for maxillary and mandibular edentulousness alone were 16.7% and 0.4% respectively. Ninety-four percent of totally edentulous and 89.6% of single-arch edentulous subjects were prosthetically rehabilitated. In the follow-up study, 7.7% of the originally dentate women and 6.7% of men had lost the rest of their teeth. For the new totally edentulous subjects the mean number of teeth lost was 5.7 (s 3.45), most of which were incisors. In the follow-up study, 89% of the new edentulous subjects had already been edentulous in the maxilla at baseline. Among 30-39-year-olds the proportions of upper-arch and totally edentulous subjects in 1977-78/1989 were 6.7%/0.8% and 2.2%/0.8% respectively (P=0.024 for the difference between the time points). In the light of the repeated cross-sectional study, we can conclude that edentulism is very uncommon in the 30-39-year age group in this urban area.