Detection and quantification of pathogenic microorganisms in patients with chronic periodontitis before and after treatment with chlorhexidine digluconate

The aim of this study was to evaluate the efficiency of chlorhexidine digluconate solution (CHX) as an adjunct to nonsurgical therapy (NPT) of patients with chronic periodontitis (CP), by analyzing the presence and quantity of periopathogenic microorganisms in subgingival biofilm. DNA was extracted from the subgingival biofilm obtained from 40 patients with CP divided into two groups (NPT+CHX and NPT alone as control) at baseline and 2 months after the therapy. The presence of selected periodontal pathogens (A. actinomycetemcomitans, P. gingivalis, E. corrodens, T. denticola, and T. forsythia) was determined by polymerase chain reaction (PCR), while total bacterial load was assessed by quantitative PCR. The incidence of microorganisms decreased following treatment, both with NPT+CHX and NPT alone, but without reaching statistically significant difference in the NPT group. In the NPT+CHX group, a significant reduction of prevalence of two species: T. denticola (P = 0.008) and T. forsythia (P = 0.016), as well as of total microorganism count (P = 0.002) was observed two months after treatment. In conclusion, the present findings support the use of CHX as adjunctive therapy in CP.