Assessment of Microbial Contamination of Dental Prostheses

Objective: Various dental prostheses, such as crowns and dentures, are crafted in dental laboratories and then applied within the patient's mouth in dental institutions. However, dental workers rarely disinfect them before application. Therefore, we investigated the bacterial contamination of various intraoral prostheses to confirm the importance of infection control. Methods: Bacterial samples were collected from 23 dental prostheses (including six gold crowns, seven zirconia crowns, four porcelain-fused-to-metal crowns, and six dentures) in dental laboratories and dental institutions in Gyeongsangbuk-do, Korea. These samples were inoculated onto 3M Petrifilm for general aerobic bacteria and Staphylococcus aureus, respectively. The colonies that formed after 48 hours of culture were counted. Results: General aerobic bacteria and S. aureus were detected on the majority of dental prostheses, with dentures showing the highest presence (p=0.003). Neither aerobic bacteria nor S. aureus showed statistically significant differences between dental institutions and laboratories. A positive correlation was noted between the denture and the denture in terms of general aerobic bacteria and S. aureus detection (r=0.829, p<0.05). Conclusion: As a result, many bacteria were detected in most dental prostheses. Therefore, there is a need to recognize the risk of crossinfection through dental prosthesis and to establish specific infection control guidelines.