​Three major salivary glands

The three major salivary glands located around the mouth secrete saliva, and they play a vital role in the initial breakdown of starch in food by salivary amylase. There are three major pairs of salivary glands: the parotid, submandibular, and sublingual glands. Each of the three has its own characteristics. Let’s take a closer look at the introduction of the three major salivary glands and learn some other related knowledge about the salivary glands.

Salivary glands

A gland in the mouth of a human or vertebrate that secretes saliva. Humans or mammals have three pairs of larger salivary glands, namely the parotid glands, submandibular glands and sublingual glands, as well as many small salivary glands. Also called salivary glands. There are two types of salivary glands in the mouth: large and small.

Salivary gland function

The salivary glands secrete saliva, which moistens the mouth and facilitates swallowing and speaking. Human saliva contains amylase, which can initially break down starch in food.

Structural characteristics of the three salivary glands

1. The parotid gland is a pure serous gland with long intercalated ducts and shorter striated ducts. The secretions contain more salivary amylase and less mucus.

2. The submandibular gland is a mixed gland with more serous alveoli and fewer mucinous and mixed alveoli. The intercalary tube is short and the striate tube is well developed. The secretions contain less salivary amylase and more mucus.

3. The sublingual gland is a mixed gland, mainly composed of mucous and mixed alveoli, with more semilunar cells, no intercalated ducts, and shorter striated ducts. The secretion is mainly mucus.

saliva

70% of saliva is secreted by the submandibular gland, 25% by the parotid gland, and 5% by the sublingual gland. The water and mucus in saliva lubricate the mouth, and salivary amylase breaks down starch in food. Saliva also contains lysozyme. There are lymphocytes and plasma cells in the salivary gland interstitium. The IgA secreted by plasma cells combines with the protein secretory sheets produced by glandular cells to form secretory IgA, which is discharged into the oral cavity with saliva and has an immune effect.

Salivary gland tumors

Salivary gland tumors are the most common diseases in salivary gland tissue, most of which are epithelial tumors, while tumors originating from salivary gland tissue are relatively rare. The pathological types of salivary gland epithelial tumors are very complex, and different types of tumors differ in clinical manifestations, imaging findings, treatment, and prognosis.