[The diagnosis of initial carious changes]

On the basis of radiological studies on extracted teeth and of microscopic examinations of longitudinal ground sections it is stated that the early stages of dental caries are very difficult to diagnosticate clinically. Under the microscope, "healthy" teeth may also show initial carious lesions in the fissure region. The greater frequency of these changes (which might be considered to be premorbid conditions) in teeth with narrow fissures was not significant. For various reasons discussed in the present paper, it can be assumed that teeth with large fissures are earlier and more frequently prone to carious lesions.