Oral vestibule

The oral vestibule is the slit-like space situated between the lips and cheeks externally and the teeth and gingivae internally. It forms the outer compartment of the oral cavity.

Boundaries

• Externally: Lips and cheeks

• Internally: Teeth, alveolar processes, and gingivae

• Superiorly and inferiorly: Reflection of oral mucosa from lips/cheeks onto the gums forming the mucobuccal fold

• Posteriorly: Communicates with the oral cavity proper behind the last molar teeth

Contents and Features

The mucosa comprises of nonkeratinized stratified squamous epithelium which lines the oral cavity. It is raised in the midline anteriorly to give rise to frenula of the upper and lower lips.

An opening of the parotid duct (Stensen's duct) can be seen opposite to the upper second molar tooth on the buccal mucosa.