Saliva has been discussed as an important biological material for the
purpose of introducing new diagnostic tests. The important enzymes
associated with cell injury and cell death are aspartate and alanine
aminotransferase (AST, ALT), lactate dehydrogenase (LDH), and alkaline
phosphatase (ALP). Changes in the activity of these enzymes reflect
metabolic changes in the gingiva and periodontium in inflammation. In
the present study, there was a significant difference in the levels of
salivary enzymes in patients of either group and a significant decrease
in these levels was found after nonsurgical therapy in the study group.
This implies that the detection of these enzymes may be a reliable
predictor of periodontal tissue destruction and a measure of the
response to nonsurgical periodontal therapy.