Detection of Treponema denticola in Chronic Periodontitis by Quantitative Real-Time Polymerase Chain Reaction

Chronic periodontitis constitutes a significant public health issue, particularly in China. Treponema denticola is one of the bacterial species critically involved in the development of this disease. Therefore, an effort was made in this study to design a technique for isolation of DNA from gingival fluid and detection of T. denticola genes by PCR methodology. For this purpose, samples were collected from 30 patients with severe periodontitis and 20 patients with mild periodontitis. A group of 50 healthy individuals served as a control. Following the isolation of DNA from the gingival fluid by magnetic microbeads, the material was analyzed for the presence of 16S rRNA by conventional and quantitative real-time PCR protocols. This newly developed methodology identified the presence of T. denticola in all samples from periodontitis patients. Quantitative analysis of copy numbers demonstrated that the bacterial count was highest in the severe periodontitis group and intermediate in the mild periodontitis group. The smallest number of bacteria were present in healthy controls. Besides being rapid, accurate and specific, the proposed method eliminates the need for anaerobic bacterial cultures, making it applicable in a typical clinical setting.