Insufficiency of Currently used Dental Indices in Epidemiology

The World Health Organization (WHO) classifies oral diseases in two different ways: officially dental caries (K02) and gingivitis as well periodontal diseases (K.05) are diseases in the digestive system. In epidemiological surveys the so-called DMF-index values (D= decayed or M= missing or F= filled tooth/surface) are used in determining past and present caries experience and the Community Periodontal Index (CPI) of WHO is used for the region around the teeth. Prevalence may be defined as the proportion of a population that has a disease at a specific point in time. In epidemiology, a subject-specific approach is the only accepted practice which means that a patient has one or multiple diseases, the rest of the population being healthy. A certain “cut-off” value normally differentiates the healthy subjects from diseased ones. In oral epidemiology the index values are used to determine the “seriousness” of the oral diseases. Calibrated dentists/examiners may be educated in recording dental caries and attachment loss exactly at a high level of precision but unless these scientific recordings are “diagnoses”, the observations represent disease detections and assessments only without providing any prevalence or incidence values of oral diseases. The reason for that is hidden in the fact that the tools for oral health determinations are different from those for the diagnosis of oral diseases by WHO.