Sublingual gland

At a glance

English

Sublingual gland

Latin (TA2)

Glandula sublingualis

System

Digestive

Region

Whole body

Side

Paired, left and right

About the sublingual gland

The sublingual glands are almond-shaped and lie one on each side of the oral floor, beneath the lining and in front of the deep part of the submandibular gland. Each rests in a hollow on the inner surface of the mandible, the sublingual fossa, above the mylohyoid muscle, which forms its floor. Medially it lies against the genioglossus, separated by the submandibular duct and the lingual nerve. The two glands nearly meet in front, behind the lower incisors.

Unlike the parotid and submandibular glands, the sublingual gland has no proper fibrous capsule; it is a loose collection of lobules. It raises a ridge under the tongue, the sublingual fold, which runs back from beside the frenulum of the tongue. Rather than one duct, it drains through many small ducts, about a dozen or more, that open along the crest of the fold. Some lobules at the front may combine into a larger duct that joins the submandibular duct or opens beside it on the sublingual caruncle.

The secretion is mainly mucous, thick and slippery, with a small serous part. Although it adds only a modest share of the total saliva, this mucus helps to coat food and keep the lining of the mouth moist.

If one of the small ducts is damaged or blocked, mucus can leak into the surrounding tissue and collect as a bluish, painless swelling under the tongue called a ranula. A large one can extend through or behind the mylohyoid into the neck, a so-called plunging ranula. Treatment usually involves removing the affected gland. Because the lingual nerve and submandibular duct lie on its inner side, surgery here needs care.

Function and supply

Function

Secretes a mainly mucous saliva, released by numerous small ducts along the oral floor.

Nerve supply

Parasympathetic fibres that leave the facial nerve in the chorda tympani, travel with the lingual nerve and relay in the submandibular ganglion; sympathetic fibres from the plexus on the facial artery.

Blood supply

The sublingual branch of the lingual artery and the submental branch of the facial artery.