Rapid Method for the Detection of Porphyromonas gingivalis in Chronic Periodontitis

Porphyromonas gingivalis is the major cause of chronic periodontitis, a disease leading to the loss of teeth and other health complications. Therefore, an urgent need exists for a specific and rapid method for the detection of this pathogen in affected patients. The objective of this study was to test the applicability of conventional and real-time PCR protocols to detect the presence of P. gingivalis using DNA isolated by magnetic microbeads. The samples were collected from 50 patients with periodontal disease and 50 healthy subjects. Following successful isolation of DNA, the presence of P. gingivalis gene coding for its 16S rRNA was established by conventional PCR or quantitative real-time PCR. The bacteria were identified in 94% of the patients when samples of gingival crevicular fluid obtained from the active disease zone were used. The corresponding value for the quiescent zone was 44%, and for the samples collected from the plaque was 12%. P. gingivalis was not found in samples obtained from healthy subjects. Thus, the methodology developed here, based on isolation of DNA from affected periodontium by magnetic microbeads and detection of P. gingivalis DNA by conventional or quantitative real-time PCR, has been proven to be specific, sensitive, and accurate. It provides a valuable tool for a rapid and reliable diagnosis of an imminent or ongoing disease.