The Salivary Glands

The parotid glands are the largest salivary glands. They are wedge-shaped and situated in front of the ear and behind the ramus of the mandible. The apex of the wedge is the deepest part of the gland. The peripheral branches of the facial nerve (CN VII) are intimately associated with the parotid gland. This relationship is inadvertently demonstrated when an inferior dental nerve anaesthetic block is administered incorrectly, and causes a temporary drooping of the upper eye lid.

Parotid saliva is transferred along the parotid duct into the oral cavity. The thick-walled parotid duct (Stenson's duct) emerges at the anterior border of the parotid gland and runs over the surface of the masseter before hooking medially over the anterior muscle border. The orifice of the duct is covered by a small flap of mucosa called the parotid papilla and this is situated opposite the maxillary second permanent molar.

The two submandibular glands are approximately half the size of the parotids. The superficial part of the submandibular gland is wedged between the body of the mandible and the mylohyoid muscle, with the smaller deep part hooking around the posterior border of the muscle to lie on the floor of the mouth above the mylohyoid. The submandibular (Wharton's) duct runs forward, along the floor of the mouth to open into the subligual papilla, just lateral to the lingual frenum. The secretions are a mixture of serous and mucous fluids.

The sublingual glands are the smallest of the three pairs of salivary glands and are located just below the floor of the mouth beneath the sublingual folds of mucous membrane. There are numerous sublingual ducts that open into the mouth along the sublingual folds. The secretions of these glands are predominantly mucous.

The minor salivary glands consist of numerous small mucosal glands situated on the tongue, palate, buccal and labial mucosa. They produce primarily a mucous secretion.

Reference: Field A. 2003. Tyldesley's Oral Medicine. Vol. 5th Ed. Oxford University Press. UK