Prevalence of Anaerobic Bacteria (P.gingivalis) as Major Microbial Agent in the Incidence Periodontal Diseases by Meta-analysis

Statement of the problem: periodontal diseases are complex oral diseases charac-terized by bacterial-induced inflammatory destruction of tooth-supporting tissues. porphyromonas gingivalis (p. gingivalis) is a common gram-negative anaerobic oral bacteria strongly associated with periodontal disease. purpose: the present study was conducted to estimate prevalence of p. gingivalis in patients with periodontal diseases by using meta-analysis method. martials and method: different databases including pubmed, embase, scopus, the institute for scientific information (isi) web of science, and the cochrane library were searched to identify original english-language studies addressing prevalence of p. gingivalis in periodontal diseases up to december 2014. the ran-dom effects model was applied in the meta-analysis and the heterogeneity between studies was assessed using a cochran test and the i^2 index. funnel plots and egger test were used to examine publication bias. statistical analyses were performed using stata version 12. results: forty-two eligible studies published during 1993- 2016 were selected for meta-analysis. considering all the included studies, the total sample size was 5,884 individuals containing 2,576 healthy people with a mean age of 37.21±7.45 years and 3,308 periodontal patients with a mean age of 44.16±8.35 years. overall, the prevalence of p. gingivalis was 78% [95% ci: 74-81] in periodontal diseases group and 34% [95% ci: 26-41] in healthy individuals. there was a significantly higher prevalence of p.gingivalis in individuals with periodontal diseases compared to healthy subjects [78% versus 34%, respectively]. conclusion: this study indicates that p. gingivalis is highly present in subjects with periodontal diseases and it also appears in periodontally healthy people, alt-hough to a lesser extent. thus, the presence of p. gingivalis increases the chance of periodontal disease and it can be considered as a main potential risk factor.