The changing face of periodontal epidemiology.

From the time of the earliest civilisations, there has been documentation of diseases affecting the periodontal tissues. Yet it is only in the last 40 years or so that indices of the periodontal diseases were developed and the bacterial aetiology of gingivitis demonstrated. Epidemiological studies conducted in the 1950's and 1960's gave us valuable data on the prevalence and incidence of the periodontal diseases and factors associated with their aetiology and progression. However, with the introduction of new periodontal indices and refinement of criteria amidst increasing periodontal research, our perspectives of periodontal epidemiology have changed. Advanced destructive periodontal disease is less prevalent than previously thought, so there has been a shift towards risk assessment and determination of disease susceptibility. The future is promising, and possible advances in clinical and microbiological epidemiological research are considered, along with study of the host response to bacterial challenge.