[Relationship between volatile fatty acids and Porphyromonas gingivalis and Treponema denticola in gingival crevicular fluids of patients with aggressive periodontitis].

Objective: Short chain fatty acids (SCFAs), such as succinic acid, acetic acid, propionic acid, butyric acid, etc. are metabolic product of putative periodontal pathogens, which play significant roles in periodontitis. The aim of this study was to analyze the relationship between Porphyromonas gingivalis (P. gingivalis), Treponema denticola (T. denticola), and the concentration of SCFAs in gingival crevicular fluid (GCF) of patients with aggressive periodontitis (AgP).
Methods: GCF was sampled from 4 sites per individual in 20 patients with AgP and 14 healthy controls. Concentrations of SCFAs, including succinic acid, acetic acid, propionic acid, butyric acid, and isovaleric acid in the supernant of GCF were analyzed by high performance capillary electrophoresis (HPCE), P. gingivalis and T. denticola in the deposit of the same GCF were detected by PCR with their electrophoretic band quantified.
Results: The concentrations of succinic acid, acetic acid, propionic acid, butyric acid, and isovaleric acid, the prevalence and PCR band quantity of P. gingivalis and T. denticola in GCF were all significantly higher in patients with AgP than that of healthy controls. In patients with AgP, butyric acid concentration was significantly higher in P. gingivalis positive sites than negative sites [2.87 (0.99, 4.36) mmol/L vs. 0.33 (0.00, 1.44) mmol/L, P<0.05], the concentrations of succinic acid, acetic acid, propionic acid, butyric acid, and isovaleric acid were positively correlated with PCR band quantity of P. gingivalis (r value was 0.334, 0.548, 0.411, 0.493, 0.273, respectively, P<0.05); the concentrations of SCFAs were significantly higher in T. denticola positive sites than negative sites: succinic acid, 1.67 (1.15, 2.11) mmol/L vs. 0.80 (0.48, 1.06) mmol/L; acetic acid, 31.95 (23.77, 43.13) mmol/L vs.12.51 (7.57, 15.69) mmol/L; propionic acid, 11.86 (6.55, 14.98) mmol/L vs. 2.82 (1.71, 7.03) mmol/L; butyric acid, 3.45 (2.41, 4.78) mmol/L vs. 0.54 (0.00, 1.56) mmol/L; isovaleric acid, 2.23 (1.05, 3.85) mmol/L vs. 0.62 (0.00, 2.33) mmol/L. The concentrations of succinic acid, acetic acid, propionic acid, butyric acid were positively correlated with PCR band quantity of T. denticola (r value was 0.443, 0.702, 0.625, 0.557, respectively, P<0.05).
Conclusion: SCFAs concentrations reflect the quantity of P. gingivalis and T. denticola in patients with AgP, and may be an indicator to the disease progression in patients with AgP.