|
Introduction
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
- Lateral and medial pterygoids
- Digastricus muscle
- Zygomaticus muscle
- Temporalis muscle
- Platysma muscle
- Parotid duct ends in a small papillae opposite the upper fourth premolar (canid)
Histology
- Non keratinised stratified epithelium
- Some keratinisation in ruminants (see species difference section)
- Buccal glands
- Zygomatic salivary gland
Innervation
- Trigeminal nerve (CN V)
- Facial nerve (CN VII)
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.