The role of microbiological analysis as a diagnostic tool of periodontitis: a clinical study

Abstract

Oral bacteria take the the form of biofilms, which – due to their complex structure – are characterized by high resistance to many external factors. The aim of the study was to analyze the composition of subgingival biofilm in pockets ≥7 mm in an effort to answer the question whether the presence of selected bacteria of the red complex and Aggregatibacter actinomycetemcomitans may determine the diagnosis in the context of the new classification of periodontal diseases. The study included two groups of patients: 30 individuals with periodontitis Grade B (Stage III or IV) and 30 subjects with periodontitis Grade C (Stage III or IV). Each patient had at least one PPD ≥ 7 mm. The study group consisted of 26 males and 34 females, mean age 43.8 ± 15.2 years. Selected periodontal parameters were evaluated as well as microbiological quantitative and qualitative analysis was performed regarding bacterial flora in the pockets for the presence of Porphyromonas gingivalis, Treponema denticola and A. actinomycetemcomitans. The total number of bacteria was higher in patients with periodontitis Grade B, as compared to periodontitis Grade C. The number of P. gingivalis was higher in patients with periodontitis Grade B at 157.4*10^3 versus 139.9*10^3 in Grade C patients (p = 0.033). There was no difference in the occurrence of T. denticola depending on the diagnosis (p = 0.228). The presence of A. actinomycetemcomitans was confirmed only in four patients with periodontitis Grade C (p = 0.186). A moderate correlation was observed between the occurrence of P. gingivalis and T. denticola in patients with periodontitis Grade B (r = 0.51, p = 0.004). The composition of subgingival biofilm was very similar in patients with periodontitis Grade B and periodontitis Grade C. We may speculate that periododntitis grade may not be distinguished according to a simple analysis of subgingival plaque with respect to P. gingivalis, T. denticola and A. actinomycetemcomitans.