Mouth

The mouth is placed at the commencement of the digestive tube. It extends from the oral fissure anteriorly to the oropharyngeal isthmus posteriorly.

Sub-parts

The mouth is divided into two parts:

• The outer oral vestibule, which lies between the lips and cheeks externally and the teeth and gums internally, and

• The oral cavity proper, which is located within the dental arches.

Boundaries

The boundaries of the mouth or the oral cavity include:

• The lips anteriorly,

• Cheeks laterally,

• The palate superiorly, and

• The tongue and floor of the mouth inferiorly.

Epithelial lining

The oral cavity is lined mainly by non-keratinised stratified squamous epithelium, although areas exposed to greater mechanical stress, such as the hard palate and gums, are keratinised (a.k.a. the masticatory mucosa). This offers it the capacity to better support the stress upon which it is subjected during mastication.