Anatomy of the Parotid Gland

Study Notes

Parotid gland produces approximately 30% of total saliva and has a well-developed connective tissue capsule with numerous septa that subdivide the gland into lobes and lobules.
The parotid gland lies anterior to the ear between the masseter and skin.
The parotid duct opens into the vestibule next to the second upper molar.

It is the smallest of the three major salivary glands, weighing only 2-3 grams and producing about 5% of total salivary output.
It lies anterior to the submandibular gland under the tongue and opens via 10-12 ducts into the floor of the mouth.
The gland is composed of mucous tubular secretory units, many of which are capped by a small cluster of serous cells, known as serous demilunes (Giannuzi Demilunes).

It weighs around 12-15 grams and produces approximately 60% of total salivary output.
About 90% of the acini produce serous saliva, whereas the remainder manufacture a mucous saliva.
It lies along the medial aspect of the mandibular body, and its ducts open to the base of the lingual frenulum.

It is located in the PDL space, defined as the region between the cementum of the root and the bony alveolus.
It is dense irregular collagenous connective tissue with principal fiber groups, composed of type I collagen fibers, that are arranged in specific, predetermined patterns to absorb and counteract masticatory forces.
The ends of the principal fiber groups are embedded in the alveolus and cementum as Sharpey's fibers, which permit the periodontal ligament to suspend the tooth in its socket.

It is the bony socket in which the tooth is suspended by fibers of the periodontal ligament.
The alveolar process, a bony continuation of the mandible and maxilla, is divided into compartments, each known as an alveolus, that house the root.

It is attached to the enamel surface by a thin, wedge-shaped, stratified squamous nonkeratinized epithelium, known as the junctional epithelium.
As the epithelium of the gingiva approaches the tooth, it forms a hairpin turn, proceeds apically (toward the root tip) for 1 to 2 mm, and then attaches to the enamel surface by the formation of hemidesmosomes.

On the dorsal surface, there are two unequal regions: a larger anterior two-thirds and a smaller posterior one-third.
The two regions are separated from one another by a shallow, V-shaped groove, the sulcus terminalis, whose apex points posteriorly and contains a deep concavity, foramen cecum, which is a reminder of the thyroglossal canal.
The mucosa consists of squamous keratinized epithelium on the dorsal surface and squamous nonkeratinized epithelium on the ventral surface with underlying thin lamina propria.

They cover the dorsal surface of the tongue anterior to the sulcus terminalis.
There are four types of papillae: filiform, fungiform, circumvallate, and foliate papillae.
Filiform papillae are the smallest and most numerous in humans, don't contain taste buds, and serve only a mechanical role.