“Human Sputum”

Salivary fluid is an exocrine secretion consisting of approximately 99% water, containing a variety of electrolytes (sodium, potassium, calcium, chloride, magnesium, bicarbonate, phosphate) and proteins, represented by enzymes, immunoglobulins and other antimicrobial factors, mucosal glycoproteins, traces of albumin and some polypeptides and oligopeptides of importance to oral health. There are also glucose and nitrogenous products, such as urea and ammonia. The components interact and are responsible for the various functions attributed to saliva. Saliva is the product of multiple salivary glands lying beneath the oral mucosa. Each day, the human salivary glands produce almost 600ml of serous and mucinous saliva6. Once saliva passes through the ducts and enters the oral cavity, it mixes with blood cells, microorganisms and their products, oral epithelial cells and cell products, food debris and upper-airway secretions.