A subject sample comprising 100 persons (47 men and 53 women) 79 years of age and selected on a statistical basis (representing all persons of that age living in Göteborg) was the object of a general medical, clinical, and microbiologic study of the prevalence of microorganisms in the oral cavity known to cause opportunistic infections. A high prevalence of diseases and frequent medications were recorded among the participants.Staphylococcus aureuswas present in five patients andEnterobacteriaceaespecies in only one individual.Candida albicanswas not found in any samples from the palatal mucosa of the 25 individuals without dentures. Of 36 healthy denture wearersC. albicanswas found in 9 (25%). In 39 persons with denture stomatitisC. albicanswas obtained in 11 (28%) of the samples from the mucosa, 29 (74%) from the dentures, and 10 (26%) from the angulus oris. The prevalence of 5.aureus, enteric rods, andC. albicanswas low in the elderly population and, when present, correlated with the presence of dentures. No association with the patients' general health or drug use was obtained.