Screening saliva]

Oral Fluids (OF) are a complex mixture including components deriving from, salivary glands, blood, nasal and bronchial secretions, mucosal lining cells and microbiota. Therefore, OF as a mirror of the body, were suggested as an important diagnostic fluid for the detection of both, oral and systemic diseases. OF as diagnostic fluids have several advantages; their collection is easy, inexpensive and noninvasive, they are suitable for home use and for epidemiology researches, they are easy to store and ship, do not clot and enable fast detection. OF based diagnostics research accomplished a great advance during the last decade. This is mainly due to biotechnology improvements such as 2-D Fluorescence Difference Gel Electrophoresis, quantitative Mass Spectrometry and bioinformatics systems. These technologies enabled the detection of more than 3000 proteins in oral fluids, as well as the establishment of a panel of biomarkers to different human pathological conditions (i.e. periodontitis, Sjögren's Syndrome, oral cancer, pancreatic cancer etc). However, this diagnostic field has several drawbacks, mainly due to oral fluids variance composition, blood contamination as a result of gingivitis or mucosal injuries, the lack of a single established collection protocol and the presence of high abundant components in OF. This article summarizes the current research, and provides an outlook toward the foundation of this unique body fluid as a major player in the diagnostic field.