Evaluation of periopathogenic bacteria of peri-implantitis using real-time PCR in Koreans: pilot study

ABSTRACT

PURPOSE: We performed quantitative and qualitative analysis of typical periodontal bacteria using real time PCR method to investigate the microbiological difference according to the severity of peri-implant disease in Koreans. MATERIALS AND METHODS: Total of 60 implants were divided into three groups (healthy group, peri-implant mucositis group, peri-implantitis group) through periapical radiographs and clinical indices. The evaluated clinical parameters were pocket depth, plaque index, suppuration and bleeding on probing. Using a sterilized curette instrument, microbial samples were collected from the subgingival plaque and real-time PCR was performed on five periodontal bacteria. The relative expression levels of microorganisms were compared by comparative delta-CT method. RESULTS: The relative expression levels of E. corrodens and T. denticola were significantly higher in the peri-implantitis group (P < 0.017). On the other hand, the relative expression level of F. nucleatum and P. gingivalis was relatively high in the healthy implant group regardless of the severity of disease. P. intermedia was significantly lower in the healthy implant group (P < 0.017). CONCLUSION: Periodontal bacteria were detected in Koreans with peri-implant diseases, but there was no microbiological distribution similar to periodontitis.