The natural history of periodontal disease: The Java study-Origin, implementation, and results 35 years on

This review describes the origin and results of the prospective longitudinal study to test potential prognostic indicators for periodontal breakdown in a population deprived of regular dental care. Experimental gingivitis studies in individuals highly susceptible or highly resistant to periodontitis showed that bleeding on probing developed quite differently: 50% versus 18% bleeding, respectively, after 18 days of no oral hygiene. This formed, together with other clinical and microbiological parameters, the basis for the 15-year prospective study in the Java tea worker population to test potential prognostic indicators for periodontal breakdown. Evaluation showed that during the 15-year observation period of this population aged 15-25 years at baseline, the number of teeth decreased and the periodontal condition deteriorated. Gingival recession showed no increase during the first 7 years of observation, whereas a sixfold increase had occurred thereafter. Attachment loss doubled during the first 7 years, but almost tripled thereafter. Risk markers for disease onset/progression during the first 7 years of observation were age, the number of sites with subgingival calculus, and the subgingival presence of Aggregatibacter actinomycetemcomitans. Over the full period of 15 years the number of sites with a pocket depth of at least 5 mm and the number of sites with recession were identified as risk markers and male gender as a risk determinant. The prevalence of severe periodontitis amounted to 20% in 2002. Analysis showed that, already at baseline and throughout the study period, the periodontal condition in these individuals was more severe compared with the other participants. In conclusion, characteristics of susceptibility to periodontitis are already apparent in young adulthood.