ABSTRACT
ANATOMY AND PHYSIOLOGY The oral cavity The oral cavity or mouth is the point of entry of food and air into the body and the mouth and lips are essential to humans to allow speech by modifying the passage of air. This structure is also referred to as the buccal cavity, but strictly speaking this should be confined to the inner cheek area. The mouth extends from the lips to the oropharynx at the rear and is divided into two regions: (a) the outer oral vestibule, which is bounded by the cheeks and lips, and (b) the interior oral vestibule, which is bounded by the dental maxillary and mandibular arches. The oral cavity proper is located between the dental arches on which the teeth are situated. It is partly filled by the tongue, a large muscle anchored to the floor of the mouth by the frenulum linguae (Figure 3.1). At the back of the oral cavity are large collections of lymphoid tissue forming the tonsils; small lymphoid nodules may occur in the mucosa of the soft palate. This tissue plays an important role in combating infection.
