Diseases of the floor of the mouth (口底疾病)

Anatomy:

Formed largely by the anterior two-thirds of the tongue and by reflection of mucosa from the sides of the tongue to the gum on the mandible. In the midline the lingual frenulum separates the orifices of the left and right submandibular ducts. Under the mucosa lie the sublingual salivary glands.

Ranula (舌下囊腫)

Aetiology:

A cystic lesion arising from the sublingual gland. Usually presents in the floor of the mouth as a bluish, fluctuant swelling. Less commonly the “plunging ranula” can present as a lump in the neck.

Treatment:

For lesions confined to the floor of the mouth, marsupialization is usually adequate, although recurrence can occur. Plunging ranulae require formal excision via an external neck approach.

Squamous carcinoma (鱗狀細胞癌)

Clinical features:

An ulcer in the floor of the mouth which may be painful with referred otalgia. Early spread to cervical nodes, which may be bilateral, is common.

Treatment:

Excision of the tumour with plastic surgical reconstruction and adjuvant radiotherapy.