Oral health: global trends and projections.

The data bank was conceived first and foremost as an epidemiological instrument. However, it has become apparent over the years that its role is not limited solely to providing information, but that it also acts as a driving force in the generation of new information and in the development and dissemination of standard methodologies. During the 1960s, the need emerged for a systematic approach to the collection and reporting of data on oral health and diseases, based on standard diagnostic criteria, and readily applicable in all countries. Such an approach, developed by WHO, is described in the manual Oral health surveys: basic methods (1), published in 1971 and now in its third edition (1987). Experience has shown that this method is sufficiently reliable to provide data on which to plan and evaluate oral health programmes and that it is adaptable to the needs of any country, irrespective of resource level.