Factors influencing the assessment of treatment needs.

Epidemiologic surveys have provided data for health planning by estimating prevalence and incidence of diseases in populations. New ways of presenting epidemiologic data on periodontal diseases have changed our understanding of their extent and severity, and conversion of prevalence data into treatment need estimates has proved difficult. Furthermore, new concepts of the pathogenesis of periodontal diseases have questioned the validity of epidemiologic methods currently used. Treatment need assessments vary considerably between studies even when prevalence data from the same populations are similar. This may be due to lack of described goals for periodontal health. Various aspects of the concept of need for treatment are discussed. It is suggested that periodontal treatment need on a population level is defined as the intervention needed in order to change the existing periodontal condition to the described goal. Thus, treatment need assessments will have to include descriptive epidemiologic data as well as defined periodontal health goals. It is recommended that goals are described in terms compatible with the indicators used in the epidemiologic description of the disease status.