Saliva Basics – Source and Composition

Saliva’s composition and fluid dynamics are complex. Healthy saliva is primarily water and accounts for 99% of overall salivary volume. The remaining 1% is a complex mix of proteins, enzymes, mucins and buffering compounds, making saliva one of Mother Nature’s most sophisticated fluids.^2,11

Ninety percent of whole saliva comes from three major glands. The parotid gland contributes 30% to the total volume, the submandibular glands account for 60%, and sublingual glands make up the remaining 5%. All three of these glands are located outside the mouth. Saliva is introduced into the oral cavity via a duct system specific to each gland. Minor salivary glands, responsible for the final 5% of salivary composition, are found throughout the mouth. Most of the minor salivary glands are located on the inside surface of the lower lip.^2,11,31,32

Saliva has both serous and mucous components. Each gland supplies a different mix that contributes to overall oral wetness and comfort. The parotid gland is classified as serous, secreting mostly water and enzymes. The submandibular gland is considered seromucous. 90% of the flow is serous and 10% is mucous. The sublingual and minor salivary glands are mucous glands and deliver 80% of the daily mucins in the oral cavity.^2,11,31,32

Salivary mucins add three critical properties: viscosity, elasticity and stickiness properties necessary to keep the saliva in continuous contact with oral structures. Mucins prevent the feeling of mouth dryness by lubricating and wetting all oral tissues.^2,11,31,32