Mejillas

Overview

The cheeks (buccae) are important in the process of mastication (and also drinking in herbivores). Minor Salivary glands are located within the buccal musculature. The cheeks also create extensive food storage pouches in some species.

Structure and Function

The cheeks are composed of many of the muscles of mastication.

The main muscles of mastication are:

The buccinator muscle
The masseter muscle
The lateral and medial pterygoids
The digastricus muscle
The zygomaticus muscle
The temporalis muscle
The platysma muscle

The Parotid duct ends in a small papillae opposite the upper fourth premolar (canid).

Innervation

The cheeks are innervated by the trigeminal nerve (CN V) and the facial nerve (CN VII).

Histology

Non keratinised stratified epithelium

Some keratinisation in ruminants (see species difference section )

Buccal glands

Zygomatic salivary gland

Species Differences

Rodents

'Cheek pouches' are diverticula found in rodents (and monkeys) allowing food storage. The pouches can be extensive extending into the thorax with their own musculature.

Ruminants

Papillae are present on the medial surface of the cheeks. These large, pointed and densely spaced projections of keratin provide protection to the underlying epithelium due to the rough diet.