[The effect of sampling repetition on gingival crevicular fluid and aspartate aminotransferase activity]

The purpose of the present investigation was to evaluate the influence on sampling repetition of aspartate aminotransferase (AST) level with 10-minute intervals. Tests based on the composition of gingival crevicular fluid (GCF) for detection of active periodontitis and GCF require the repetition of sampling. Two 30-second samples of GCF were harvested with 10-minute intervals from 123 sites in 10 healthy subjects and 20 periodontitis patients. AST activity of the first samples in periodontitis subjects were approximately 7.8% greater than that of the second samples. The difference were not significant (P > 0.05). But in healthy subjects the difference were significant (P < 0.05). AST activity correlation positively with bleeding index (BI) and probing pocket depth (PD).