Definition:
The mouth, or buccal cavity, formed by the cheeks, lips, hard and soft palates, and tongue; receives food and saliva and initiates digestion, and forms words in speech.

Structures of the oral cavity

Structure	Description	Function
Cheeks	Lateral muscular walls; lined with nonkeratinized stratified squamous epithelium	Secure and manipulate food
Lips	Surround oral orifice; fleshy organs containing orbicularis oris muscle and abundant sensory receptors	Determine the temperature and texture of food; formation of words in speech
Palate	Consists of hard and soft portions lined with mucous membrane; palatal rugae of hard palate, and uvula as an extension of soft palate	Secure food during mastication (chewing) and deglutition (swallowing); uvula closes off the nasopharynx during deglutition
Tongue	Occupies floor of mouth; muscular organ covered with mucous membrane which contains taste buds	Manipulates food and assists in deglutition; senses the tastes of food; formation of words in speech
Teeth	Secured in alveoli (sockets) of maxillary and mandibular bones; exposed crowns extending from gingivae (gums)	Cutting and shearing food (incisors and canines), and masticating (crushing and grinding) food (premolars and molars)

Clinical Information

Chilitis. Inflammation of the lips.
Halitosis. Offensive breath odor. It may result from dental caries, certain diseases, or eating particular foods.
Pyorrhea. The discharge of pus at the base of the teeth at the gum line.
Trench mouth. A contagious bacterial infection that causes inflammation, ulceration, and painful swelling of the floor of the mouth.