Submandibular gland

The paired submandibular glands (historically known as submaxillary glands) are major salivary glands located beneath the floor of the mouth. They each weigh about 15 grams and contribute some 60–67% of unstimulated saliva secretion; on stimulation their contribution decreases in proportion as the parotid secretion rises to 50%.Salivary glands.Mandible. Inner surface. Side view.Distribution of the maxillary and mandibular nerves, and the submaxillary ganglion.Mucus cell are identifiable by the lack of color in their cytoplasm, while serosal cells have a basophilic color.Submandibular gland inflammation as seen on ultrasoundSubmandibular glandSubmandibular glandSubmandibular gland lateral viewSubmandibular glandSubmandibular gland - right viewSubmandibular gland - frontal viewSubmandibular glandMuscles, arteries and nerves of neck.Newborn dissection.Muscles, arteries and nerves of neck.Newborn dissection.Muscles, nerves and arteries of neck.Deep dissection. Anterior view.Submandibular gland The paired submandibular glands (historically known as submaxillary glands) are major salivary glands located beneath the floor of the mouth. They each weigh about 15 grams and contribute some 60–67% of unstimulated saliva secretion; on stimulation their contribution decreases in proportion as the parotid secretion rises to 50%. Lying superior to the digastric muscles, each submandibular gland is divided into superficial and deep lobes, which are separated by the mylohyoid muscle: Secretions are delivered into the submandibular duct on the deep portion after which they hook around the posterior edge of the mylohyoid muscle and proceed on the superior surface laterally. The excretory ducts are then crossed by the lingual nerve, and ultimately drain into the sublingual caruncles – small prominences on either side of the lingual frenulum along with the major sublingual duct. The gland can be bilaterally palpated (felt) inferior and posterior to the body of the mandible, moving inward from the inferior border of the mandible near its angle with the head tilted forwards. Lobes contain smaller lobules, which contain adenomeres, the secretory units of the gland. Each adenomere contains one or more acini, or alveoli, which are small clusters of cells that secrete their products into a duct. The acini of each adenomere are composed of either serous or mucous cells, with serous adenomeres predominating. Some mucous adenomeres may also be capped with a serous demilune, a layer of lysozyme-secreting serous cells resembling a half moon. Like other exocrine glands, the submandibular gland can be classified by the microscopic anatomy of its secretory cells and how they are arranged. Because the glands are branched, and because the tubules forming the branches contain secretory cells, submandibular glands are classified as branched tubuloacinar glands. Further, because the secretory cells are of both serous and mucous types, the submandibular gland is a mixed gland, and though most of the cells are serous, the exudate is chiefly mucous. It has long striated ducts and short intercalated ducts.