Comparison of the levels of aspartate aminotransferase and clinical parameters pre- and post-initial therapy and periodontal surgery

Aspartate aminotransferase (AST) is an enzyme used clinically as an indicator of cell injury in pathological conditions in which cytoplasmic enzymes are liberated into the extracellular fluid, increasing the AST concentrations in the serum. Elevated gingival crevicular fluid (GCF) levels of AST serve as a useful indicator of the disease activity of periodontitis. In this study, we measured the AST levels in GCF from chronic periodontitis patients before and after initial therapy or periodontal surgery (periodontal regeneration therapy using Emdogain^® gel) using a Periodontal Tissue Monitor (PTM) kit, and investigated the relationships among the AST levels (PTM values) and the probing pocket depth (PPD), clinical attachment level (CAL) and bleeding on probing (BOP). After the initial therapy, the PTM values improved at 22 out of 38 treatment sites. Among the 22 sites, PPD at 20 sites, CAL at 15 sites, and BOP at 21 sites either improved or showed no change. After periodontal surgery, the PTM values improved at 42 out of 56 treatment sites. Among the 42 sites, PPD at 39 sites, CAL at 32 sites improved, and BOP at 41 sites either improved or showed no change. Next, we explored the relationship between the PTM values and the mean PPD and CAL after periodontal surgery. In the 42 sites that showed improved PTM values, the mean PPD and CAL were significantly decreased. However, in the 14 sites that showed no change or deterioration of the PTM values, only the mean PPD was significantly decreased. The results suggest that sites with improved PTM values after periodontal surgery might not only show shallow PPDs, but also CAL gain. When we compared the amount of CAL gain and PTM values after periodontal surgery, the sites showing greater CAL gain tended to show lower PTM values. These studies suggest that measurement of the AST levels in GCF is useful for predicting the prognosis of periodontal disease. Nihon Shishubyo Gakkai Kaishi (J Jpn Soc Periodontol) 56(4)：390-398, 2014.