The periodontal tissues may be exposed to a variety of free radicals during inflammatory reactions, particularly where polymorphonuclear leukocytes and macrophages are in abundance and respond with significant quantities of oxygen-derived free radicals, which may cause significand cellular and tissue damage. The reactive oxygen species are produced either through specific enzymatic systems with the purpose to generate free radicals, or as a consequence of the transport chains of electrons or metabolic paths. Saliva may constitute a first line of defence against free radical-mediated oxidative stress, since the process of mastication promotes a variety of such reactions, including lipid peroxidation. On the other hand, saliva is also rich in antioxidants, mainly uric acid, with lesser contributions from albumin, ascorbate and glutathione.
Keywords:- ANTIOXIDANT CAPACITY
- REACTIVE OXYGEN SPECIES
- saliva