Normal Salivary Gland Anatomy
Two parotid glands are located in front of the ear over the jaw
joints on each side. Two submandibular glands are located in the upper
neck just below the jaw. Two sublingual glands are located in the floor
of the mouth. Many minor salivary glands are found throughout the upper
The Parotid gland consists of a superficial (outer) and a deep
(inner) part which are separated by the tree like terminal branches of
the facial nerve which are responsible for facial movement. Lymph nodes
are present within the gland.
Saliva leaves the gland through Stensen's duct which pierces the
facial muscles and enters the mouth through the cheek opposite the
second upper molar tooth.
Saliva flow is stimulated by chewing and the presence of food in the
mouth, particularly sour substances. The stimulus is mediated via
parasympathetic nerve fibres carried on the auriculotemporal nerve to
the parotid gland.
The submandibular gland consists of inner and outer parts separated
by the myelohyoid muscle. The duct leaves the deep part of the gland and
enters the floor of the mouth in the midline to meet its opposite
partner. The deep part of the gland is intimately related to the
hypoglossal nerve which moves the tongue, and the lingual nerve which
provides sensation to the front half of the tongue.
Saliva flow from the submandibular gland is stimulated via
parasympathetic (chorda tympani) nerve fibres carried along the lingual
Classification of Salivary Gland Enlargement
- Acute: mumps, acute suppurative sialoadenitis and abscesses
- Chronic: Granulomatous diseases (sarcoid, cat scratch, tuberculosis,
actinomycosis), chronic/recurrent sialoadenitis, Sjogrens syndrome.
- Pleomorphic adenoma
- Warthins tumour
- Vascular tumours and cysts
- Adenoid cystic tumours
- Mucoepidermoid tumours
- Carcinoma in pleomorphic adenoma
- Squamous cell carcinoma
- Acinic cell tumour