Occlusal hidden caries: a bacteriological profile.

Eleven teeth from nine patients with occlusal caries lesions beneath an apparently intact enamel surface were treated. Two dentine samples, one from the dentinoenamel junction (Sample A) and one just before all the caries appeared to be removed clinically (Sample B), were taken under aseptic conditions and examined for bacteria. In all cases, the A samples and in ten cases the B samples contained mutans streptococci, lactobacilli or both, while in ten cases the dentine after opening was soft with a light color. This suggests that we are dealing with active caries lesions, which should be treated as such. The salivary data of the patients group were compared with the salivary data of the control group. Although the buffer capacity of the groups were not significantly different (chi-square), further analysis revealed that a significant relationship could be found between the group and the buffer capacity (Kendall's Tau C). While the other salivary components (numbers of mutants streptococci per ml saliva and the secretion rate) showed no significant differences. Unfortunately these occlusal caries lesions are not detected with the present criteria used in epidemiological surveys.