Longitudinal study of volatile fatty acids in the gingival crevicular fluid of patients with periodontitis before and after nonsurgical therapy.

BACKGROUND AND
OBJECTIVE: Short-chain fatty acids (SCFAs) are important metabolic products of subgingival organisms and their concentrations are associated with the status of inflammation. The purpose of this study was to observe and analyze the change in concentration of SCFAs in the gingival crevicular fluid of patients with chronic periodontitis before and after periodontal treatment.
MATERIAL AND METHODS: Gingival crevicular fluid samples were taken from 21 patients with chronic periodontitis before periodontal treatment and 2 wk, and 2, 4 and 6 mo after treatment. The concentrations of six different SCFAs in the gingival crevicular fluid were measured using high-performance capillary electrophoresis. The presence of porphyromonas gingivalis in the same pretreatment gingival crevicular fluid samples used to measure SCFAs was analyzed using PCR amplification.
RESULTS: Two weeks after periodontal treatment, the concentrations of lactic acid, propionic acid, butyric acid and isovaleric acid in the gingival crevicular fluid of patients with chronic periodontitis had decreased to the levels found in the healthy control group. However, the concentration of formic acid had increased. Statistically significant differences were found in the levels of these SCFAs before and after treatment. In the longitudinal observation, the concentrations of butyric acid and isovaleric acid in the gingival crevicular fluid had increased to a high level 2 mo after treatment. At the last two study time-points (4 and 6 mo after treatment), butyric acid and isovaleric acid were still present at a high level and showed a tendency to continue to increase. In contrast, the concentration of formic acid in gingival crevicular fluid showed a gradual decrease over the study period.
CONCLUSIONS: The concentration of formic acid in the gingival crevicular fluid has an inverse relationship with the severity of periodontitis, whereas the increased concentrations of butyric and isovelaric acids during the long-term observation period after therapy may indicate the status of recolonization of periodontal pathogens and reflect the subgingival ecology. These two fatty acids could be used as indicators for the development and progression of periodontitis.