Submandibular gland

The submandibular glands (historically also known as the submaxillary glands) are paired salivary glands located behind and below the ramus of the mandible in the submandibular triangle. They secrete mixed serous and mucous saliva that is excreted into the oral cavity via the submandibular duct that connects the gland to the floor of mouth.

Gross anatomy

Its lower superficial lobe continues as smaller deep lobe by wrapping around the posterior border of the mylohyoid. The superficial lobe of the submandibular gland is in the submandibular space, and the deep lobe is situated in the sublingual space where it can be palpated intraorally. Posteriorly it is separated from the parotid gland by the stylomandibular ligament.

It is encapsulated during development and does not normally contain lymph nodes. There is a fibrous capsule surrounding the gland, formed by the split layers of the investing layer of the deep cervical fascia.

Relations

The cervical branch of the facial nerve and facial vein are its superficial relations to the inferior surface of the superficial lobe. The facial artery grooves posterosuperiorly to the gland and descends to the inferior border of the mandible, where it can be palpated, and to ascend in front of the masseter muscle.

The deep part of the gland extends forwards and lies between mylohyoid inferolaterally, and hyoglossus and styloglossus medially.

Arterial Supply

The submandibular gland is supplied mainly by the facial, lingual, and submental artery,

Venous drainage

It drains into the facial and submental veins.

Innervation

Autonomic innervation is from the lingual nerve via the submandibular ganglion with parasympathetic fibres arising from the chorda tympani and sympathetic fibres from the superior cervical ganglion.

Variant anatomy

• congenital absence +/- contralateral submandibular gland hypertrophy ⁴

Related pathology

• sialolithiasis
• submandibular gland enlargement