[The contents of caries-free fissures of human premolars and molars].

The contents of the fissures of occlusally caries-free human premolars and molars were examined for colour, consistency and removability, and under the microscope. The results obtained were brought in relation to the forms of the fissures. Superficial fissure contents contain micro-organisms, are similar to materia alba and may be considered as acquired. Contents from the depth of narrow fissures contain epithelial cell-like structures but no or very few bacteria and seem to be remnants from the time when the teeth were being formed.