Evaluation of the Presence of Porphyromonas gingivalis and Its Correlation With Signs and Symptoms in Endodontic-Periodontal Lesions: A Cross-Sectional Study

Introduction: Endodontic-periodontal lesions are infections that simultaneously affect the pulp and periodontal tissues, often leading to complex clinical presentations. Porphyromonas gingivalis, a key periodontal pathogen, has also been identified in root canal infections, suggesting a potential role in the severity and progression of endodontic-periodontal lesions. Its virulence factors contribute to tissue destruction, inflammation, and immune modulation. However, data correlating its presence with specific clinical signs and symptoms in endodontic-periodontal lesions remain limited. This study aims to evaluate the presence of Porphyromonas gingivalis and its association with clinical and radiographic parameters in endodontic-periodontal lesions. Methodology: Clinical and radiographic findings considered for the diagnosis of endodontic-periodontal lesions were recorded from 32 patients, following which root canal samples were obtained and transported for identification of P. gingivalis by culture. Fifteen root canal samples positive for P. gingivalis species confirmed by culture were considered for the study. The results were assigned, and statistical analysis was done using the chi-square test, Fisher's exact test, and the Mann-Whitney U test. Results: P. gingivalis was detected in 46.9% (15/32) of endodontic-periodontal lesions. Among P. gingivalis-positive cases, the sinus tract was present in 66.7% (2/3), swelling in 71.4% (5/7), tenderness on percussion in 46.9% (15/32), and discoloration in 60% (3/5). The organism was more frequent in symptomatic cases (65.5%; 15/23), with statistically significant associations observed for pain (P < 0.05) and furcation involvement (88.9%; 8/9; P < 0.05). On periodontal evaluation, P. gingivalis-positive patients had greater mean pocket depth (5.33 mm) and attachment loss (4.93 mm) compared to negative patients (P < 0.05). Higher PAI scores (≥4) were recorded in 80% (12/15) of positive cases, with score 5 in 53% (8/15), score 4 in 26.7% (4/15), and score 3 in 20% (3/15). Periapical lesion size between 3 and 5 mm was observed in 60% (9/15) of positive cases, while 40% (6/15) had lesions >5 mm, showing a significant association with P. gingivalis presence (P = 0.001). Conclusion: P. gingivalis is strongly associated with clinical signs and symptoms and its detection frequency positively correlates with the severity of endodontic-periodontal lesions.