Identification of Porphyromonas gingivalis in Periodontally Healthy Adults and Chronic Periodontitis Patients Using Polymerase Chain Reaction

Context: Periodontitis, a complex multifactorial, polymicrobial infection, involves deterioration of the supporting tissues surrounding teeth. Among the polymicrobiota, Porphyromonas gingivalis is a keystone pathogen implicated in chronic periodontitis. Aim: Identification of P. gingivalis in periodontally healthy adults and chronic periodontitis patients using polymerase chain reaction (PCR). Settings and Design: This cross-sectional study was conducted at the Department of Periodontics, KLE V. K. Institute of Dental Sciences, Belgaum. The 60 patients were selected from the outpatient department considering the selection criteria, using convenience sampling. Materials and Methods: Patients were categorized into three groups: periodontally healthy, moderate, and severe periodontitis. Plaque index, probing depth, and clinical attachment level (CAL) were measured. The plaque samples were collected from patients and were cultured and analyzed for black-pigmented colonies, followed by biochemical characterization and DNA isolation. Samples showing bacterial DNA bands were further selected for PCR analysis with species-specific primer to confirm P. gingivalis. Statistical Analysis:Descriptive analysis was done using Kruskal-Wallis ANOVA, Chi-square, and Mann-Whitney U-test (P < 0.05). Results: Age and gender showed no significance in the prevalence of P. gingivalis. P. gingivalis was absent in periodontally healthy patients and detected in 10% of moderate periodontitis and 50% of severe periodontitis patients (P = 0.0001). No statistical significance with the prevalence of P. gingivalis was observed between moderate and severe periodontitis patients. In severe periodontitis patients, P. gingivalis was significantly associated with higher mean pocket probing depth scores (P = 0.0073) and CAL scores (P = 0.0022). Conclusion: The prevalence of P. gingivalis was significant in both moderate and severe periodontitis patients; however, a higher prevalence was observed in severe periodontitis patients. PCR analysis revealed a significant rise in the frequency of P. gingivalis with an increased periodontal pocket depth and clinical attachment loss, indicating a correlation with the severity of periodontal destruction.