Salivary infectious agents and periodontal disease status

The potential of salivary microorganisms to diagnose periodontal disease and to guide periodontal treatment is a research topic of current interest. This study aimed to determine whether the salivary counts of periodontopathic microbes correlated with the periodontal pocket counts of the same infectious agents, and whether the salivary counts of the test infectious agents could distinguish among individuals with periodontal health and various types of periodontal disease.

The study included 150 systemically healthy adults, of whom 37 were periodontally healthy, 31 had gingivitis, 46 had chronic periodontitis and 36 had aggressive periodontitis. Each study subject contributed microbial samples from the two deepest periodontal pockets of the dentition and from whole saliva. Aggregatibacter actinomycetemcomitans, Campylobacter rectus, Fusobacterium nucleatum, Porphyromonas gingivalis, Prevotella intermedia, Tannerella forsythia and Epstein-Barr virus were identified using the TaqMan real-time PCR methodology. Statistical analysis was performed using the Mann-Whitney U-test and the receiver operating characteristic statistics.

C. rectus, F. nucleatum, P. gingivalis, P. intermedia and T. forsythia occurred with significantly higher copy-counts in salivary samples from patients with gingivitis, chronic periodontitis and aggressive periodontitis than from periodontally healthy individuals. A. actinomycetemcomitans only showed higher salivary copy-counts in subjects with aggressive periodontitis compared with subjects with healthy periodontium, and the salivary copy-counts of Epstein-Barr virus did not reveal any significant difference among the four subject groups studied. The diagnostic sensitivity for periodontitis was 89.19 for P. gingivalis and for T. forsythia and 86.49 for P. intermedia, with specificities ranging from 83.78 to 94.59. The optimal copy-counts per mL saliva for identifying periodontitis were 40,000 for P. gingivalis, 700,000 for T. forsythia and 910,000 for P. intermedia.

Salivary copy-counts of P. gingivalis, T. forsythia and P. intermedia appear to have the potential to identify the presence of periodontitis, whereas the salivary level of the other test infectious agents may possess little or no diagnostic utility. Longitudinal studies are warranted to determine the ability of salivary copy-counts of major periodontopathic bacteria to predict future periodontal breakdown.