The objectives of the study were to analyse changes in tooth mortality among adults in Västerbotten County, Sweden, between 1990 and 2002 and determine whether socioeconomic factors, general health, smoking, and dental care habits influenced tooth mortality. The study was based on samples drawn from the adult population in Västerbotten County in 1990 and 2002. The studied age groups were 35-, 50-, and 65-year-olds. In 2002 75-year-olds were included. The surveys comprised a clinical examination and a questionnaire.The latter focused on oro-facial symptoms, socioeconomic factors, general health, smoking, and dental care habits. Complete data were obtained from 715 individuals in 1990 and from 768 individuals in 2002.Variables used to depict tooth mortality were edentulousness, occlusal supporting zones (Eichner index), and number of teeth. The prevalence of edentulousness in Västerbotten County decreased from 12.7% in 1990 to 3.7% in 2002 (P < 0.001). The mean number of teeth increased in all age groups between 1990 and 2002, and so did the number of individuals with tooth contact in all occlusal supporting zones and no gaps between teeth. Low educational level, weak economic status, smoking, and irregular visits to the dental clinic were all significantly related to increased tooth mortality. Between 1990 and 2002 tooth mortality decreased significantly in the adult population of Västerbotten County, Sweden. Cross-sectional analysis identified socioeconomic factors, smoking, and irregular use of dental care services as being related to tooth mortality in both 1990 and 2002.