Abstract
The mouth is a window to the body, and saliva plays an essential role in maintaining the integrity of oral structures. Saliva is that complex fluid that controls oral health through specific and nonspecific physical and chemical properties. The significance of saliva in our everyday activities and its medicinal properties are often taken for granted. However, when disruptions occur in the quality or quantity of saliva in an individual, he or she will likely experience detrimental effects on oral and systemic health. Often head and neck radiotherapy have serious and detrimental side effects on the oral cavity, including the loss of salivary gland function and a persistent complaint of a dry mouth (xerostomia). Thus, saliva has many beneficial functions that are essential to our well-being. Although saliva has been extensively investigated as a medium, few laboratories have further studied saliva’s role in maintaining oral and general health and found saliva as a fascinating biological fluid that possesses the features of a perfect diagnostic tool. The presence of microbial, immunologic and molecular biomarkers in saliva offers these unique opportunities. These biomarkers aid in the early diagnosis and monitoring of oral diseases such as, dental caries, oral malignancies, infectious diseases and many more. Saliva has proved to be a good substrate for the early detection of oral diseases to evaluate therapeutic responses.