FIMA gene as a target to detect porphyromonas gingivalis from saliva in periodontitis patients by using real time-pcr

Porphyromonas gingivalis is a gram-negative anaerobic bacterium that is considered a major causative agent of chronic periodontitis. This study aimed to establish a PCR method that is applicable for specimens with limited amounts and with no sample processing to detect the presence of P. gingivalis and types fimA directly from oral rinse samples. Oral rinse samples were collected from 12 periodontally healthy individuals and 18 individuals with periodontitis. PCR primers were designed to amplify the fimA gene and differentiate between the six fimA types of P. gingivalis. PCR amplification of the fimA gene successfully detect the presence of the P. gingivalis in 17 of 18 samples (94.4%) and the genotyping PCR identified all six fimA types of P. gingivalis directly from the oral rinse samples without any prior DNA extraction or purification steps. The results suggest a high prevalence of P. gingivalis in individuals with periodontitis and identify the most prevalent fimA types in this population. The most prevalent fimA genotype was Ib, with a frequency of 33.33%. The next most common genotype was II, with a frequency of 27.78%, followed by IV with a frequency of 16.67.