Saliva as a Diagnostic Tool in Oral Diseases

Abstract

Saliva is a body fluid, which is secreted from 3 major salivary glands (parotid, submandibular and sublingual) and many minor salivary glands. It contains organic and inorganic substances with 99% water, and has several functions such as contribution to articulation, digestion, cleansing and protection of the oral mucosa, and antimicrobial effects. The concentration of saliva's substances vary according to the responses to physiological processes in the human body. Containing genetic materials such as DNA and RNA also highlights saliva as a potential diagnostic tool. Saliva analysis has advantages such as being cheaper, non-invasive, easier patient cooperation, and low technical sensitivity compared to blood tests; it can be used in the diagnosis of many diseases or routine risk assessments. It is also promising for its advantages in collection and storage of the samples. Advances in molecular biology, genomics, and proteomics have revealed the importance of saliva in the detection of many diseases, coining the term salivaomics. The early diagnosis of the diseases in which symptoms can be seen in late stages, may provide an easier treatment and improve the prognosis. In this review, the biomarkers of saliva in the presence of different diseases and the advantages of their use in diagnosis were examined.