. Clinicopathologic study that evaluated whether dentinal carious lesions are colonized by candidal organisms and if so, whether there is a relationship between dentinal carious lesion colonization and clinical oral candidiasis,or OC, in HIV infection. Two groups: 30 consecutively treated HIV-positive patients and 30 consecutively treated HIV-negative patients. OC was diagnosed only in HIV-positive patients (40 percent). The dentinal carious lesion pattern in both groups was similar in occlusal, root and proximal caries. Candidal colonization of carious dentinal tubules was more frequent in HIV-positive subjects than it was in HIV-negative subjects. This research shows that it may be important to restore dentinal caries in HIV-infected patients to remove a protected niche for candidal organisms.