Saliva is essentially a heterogeneous fluid that comprises proteins, electrolytes, glycoproteins, small organic compounds and molecules transported from the blood, which constantly bathes the inner lining of the mouth and teeth. It serves as an ion reservoir, a cleansing solution, a buffer and a lubricant. Apart from its other host-protective assets, saliva could establish an initial line of defense against oxidative stress. This is because the mastication and digestion process of ingested foods promotes a range of responses, including lipid peroxidation.
Furthermore, when gingival inflammation occurs, the flow of gingival crevicular fluid boosts changes in saliva composition with yields from the inflammatory response. As such, this could play a role in modulating and/or controlling oxidative damages within the oral cavity. As a result, the antioxidant capacity of saliva has triggered increasing interest, which has caused a growth of methods appropriate for saliva antioxidant capacity evaluation.