GPT and periodontitis: Lactate dehydrogenase (LDH), alkaline phosphatase (ALP), aspartate aminotransferase (AST), and alanine aminotransferase (ALT) are markers of cellular damage and inflammation; there is evidence for an association between salivary levels of all these mediators and periodontitis [109–114] with the exception of one study which reported no association with ALP, AST, or ALT [111] and another which failed to reproduce significant association with salivary LDH [75].