Thesis (M.Sc.)--Chulalongkorn University, 2012

Objective To investigate periodontal pathogenic bacteria, Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, and Prevotella intermedia in the healthy peri-implant sulci of smokers or nonsmokers using 16S rRNA-based PCR. Materials and Methods Patients who received implant-supported fixed partial prostheses were randomly selected and categorized in to smokers (n=7) and nonsmokers (n=7).Sterile paper points were used to collect submucosal samples from healthy peri-implant sulci, and then DNA was extracted. Endpoint and quantitative PCR were performed to identify Porphyromonas gingivalis, Treponema denticola, Tannerella forsythia, Prevotella intermedia and total bacteria. Results The prevalence of periodontal pathogenic bacteria was higher in smoker with statistical significant different in Treponema denticola by Fisher’s exact test (p=0.029). Quantitative PCR showed the ratio of Treponema denticola to total bacteria were significantly higher in smokers when compared to nonsmokers by Mann-Whitney U Test (p=0.026). Conclusions These results suggested that smoking was the environmental factor that strongly influenced the peri-implant microbiota and success rate of the dental implant.