FREQUENCY-DISTRIBUTION OF INDIVIDUALS AGED 20-70 YEARS ACCORDING TO SEVERITY OF PERIODONTAL-DISEASE EXPERIENCE IN 1973 AND 1983

The aim of this study was to compare changes in periodontal status of a Swedish population over a 10-year period expressed as frequency distributions of individuals according to severity of periodontal disease experience. The study involved 600 randomly selected individuals evenly distributed into age groups 20, 30, 40, 50, 60 and 70 years, examined in 1973 and another randomly selected group of 597 individuals similarly age distributed and examined in 1983. Based on clinical data and full mouth intraoral radiographs all individuals were classified into 5 groups according to severity of periodontal disease experience. In 1983, 23% of the individuals were classified as having healthy periodontal tissues, group 1, compared to 8% in 1973. The changes were most pronounced in the age groups 20 and 30 years, among whom 58% and 35%, respectively, were registered as having healthy periodontium in 1983. The prevalence of individuals with gingivitis without signs of lowered periodontal bone level, group 2, was 22% in 1983 compared to 41% in 1973. In all, 49% of the dentate population in 1973 and 45% in 1983 showed no marginal alveolar bone loss. Moderate peridontal bone loss, group 3, was found in 41% of the population in 1983 compared to 47% in 1973. Among 30-, 40-, and 50-year-olds, there were more, and among 60- and 70-year-olds, fewer individuals in this group in 1983 compared to 1973. 96% of the dentate population were classified as belonging to groups 1, 2 or 3 in 1973 compared to 86% in 1983. Individuals with severe periodontal bone loss, group 4, were few in 1973 and not found before the age of 50. In 1983, the prevalence of individuals belonging to group 4 had increased and amounted to 1% of the 20-year-olds, 9% of the 50-year-olds, 25% of 60-year-olds and 38% of 70-year-olds. On the average, 11% of the dentate population were found in group 4 in 1983 compared to 2% in 1973. The prevalence of individuals belonging to group 5, i.e., alveolar bone loss around the majority of the teeth exceeding 2/3 of the normal bone height and the presence of angular bony defects and/or furcation defects, was 1% in 1973 and 2% in 1983. There were no individuals younger than 40 years in this group. Based on gingivitis and probing pocket scores, 33% of the individuals classified to groups 3 and 4 were considered periodontally healthy although with reduced periodontal support. In periodontal disease severity group 5, no individual was considered periodontally healthy.