What are the boundaries of the oral cavity proper?

The oral cavity proper is the enclosed space behind the dental arches, bounded by the alveolar ridges and extending to the oropharynx. It communicates posteriorly with the oropharynx through the oropharyngeal isthmus, which is bordered by the soft palate superiorly, the tongue inferiorly, and the palatoglossal arches laterally.

What structures form the floor of the mouth?

The floor of the mouth is a horseshoe-shaped region beneath the anterior tongue, above the mylohyoid muscle. Key features include the frenulum linguae (a median fold connecting the tongue to the floor), sublingual papilla (elevations where the submandibular duct opens), and sublingual fold (mucosa overlying the sublingual gland).

How is the roof of the oral cavity proper structured?

The roof is formed by the palate, which separates the oral and nasal cavities. It consists of the hard palate (anterior two-thirds, bony with transverse folds) and soft palate (posterior one-third, muscular and fibrous, ending in the uvula). A median raphe extends from the uvula to the incisive papilla.

What is the oropharyngeal isthmus and its function?

The oropharyngeal isthmus (isthmus of fauces) is the opening between the oral cavity proper and the oropharynx, bounded by the soft palate, tongue, and palatoglossal arches. During swallowing, approximation of these arches helps close off the oral cavity from the oropharynx.

What clinical condition is associated with the floor of the mouth?

Ludwig’s angina is a cellulitis of the floor of the mouth, often due to dental infections like carious molars. It can spread to submandibular and submental regions, potentially elevating the tongue and obstructing swallowing or breathing.

What are the positional terms used in the oral cavity?

Positional terms in the oral cavity include lingual (towards the tongue), palatal (towards the palate or upper teeth), buccal (towards the cheek, posterior-lateral), and labial (towards the lips, anterior).

Oral Cavity Proper – Boundaries, Floor & Roof