ABSTRACT
Microbial contamination of removable denture and their contact with saliva and oral tissues can cause microbial cross-contamination among dental clinic personnel, dental laboratories and patients. These microorganisms can cause unpredictable infections especially systemic, pneumonia and even cardiac infections in elderly and immunosupressed patients. The aim of this study was to identify the microorganisms on the surface of removable prostheses ready for delivery [new dentures] in Yazd dental laboratories Fifty five new removable complete dentures were randomly selected from 5 Yazd dental laboratories. All dentures were washed by 100ml of sterile normal saline, centrifuged and precipitants were used for culture on the specific microbial media. Finally, the isolated aerobic, anaerobic microbial colonies and isolated fungi were identified according to diagnostic tests. Bacterial contaminations were seen in all prostheses whereas 58.2% showed fungal contaminations. Staphylococcus, nonpathogenic Neisseria spp, Corynebacteria, Acenitobacteria, E. coli, and Entrobacter spp were the common isolated bacteria in the current study. Saprophyte fungi such as Aspergillus, penicillium, mucor and yeasts especially Candida species were the most isolated fungi from dental prostheses in the present study. Results of the present study showed bacterial and fungal contamination even on newly made prostheses. It seems that control and prevention of cross-contamination should be taken more seriously in dental practices and laboratories