The oral cavity is located under the nostrils and is limited in five of its six faces by soft walls, that is to say by striated muscular walls. The elements contained in the oral cavity are: the tongue and the teeth. In addition, attached to the oral cavity are the major salivary glands: parotid, submandibular and sublingual whose excretory ducts open in it. We will review the elements of the oral cavity.
The anterior area of the oral cavity
Anterior wall of the buckle area, is formed by the lips, muscular skin folds (orbicular muscle) and mucosa that delimit the buckle opening between them. The skin of the free or red edge of the lip is thin, richly irrigated and innervated, allowing to discriminate the temperature and texture of the food.
Posterior area of the oral cavity
Posterior wall of the mouth or mouth, is formed by the soft palate, mucous and muscle fold that is inserted into the bony palate. It presents elevator muscles and depressors of the palatal veil to allow it to function as a valve that will order the transit of food or air to the pharynx. The anterior or buckle aspect of the soft palate is very sensitive, and its stimulation generates the reflex.
On each side, between the anterior and the posterior pillar, the tonsil or palatine tonsil.
Lateral walls of the oral cavity
Lateral walls of the mouth, formed by the cheeks, constituted by muscular skin planes (buccinators muscle) and mucosa from the outside inwards. The mucosa is thick, whitish and supports the rubbing of the dental arches during chewing.
Lower area of the oral cavity
Lower wall or floor of the mouth or oral cavity, which becomes evident when the tongue is raised. It is covered by a very thin, transparent mucosa, which allows to see the underlying structures; this mucosa is so thin that some drugs can be administered sublingually for absorption. On this floor of the mouth lies the free part of the tongue.
Upper wall of the mouth
Upper wall, hard wall formed by the bony palate, is covered by a thick mucosa of masticatory type, which supports the pressure of food during chewing as well as high temperatures. In the anterior area of the palate, a series of very characteristic roughness is detected.
The presence of the upper and lower dental arches will separate two areas in the oral cavity.
Centrally with respect to the arcades is the oral cavity itself, which houses the tongue. These two regions, the vestibule and the oral cavity, communicate through the retro molar space, located behind the last molars.
Tongue: organ constituted by striated musculature, covered by mucosa. The mucosa of the dorsal face is very specialized, covered by lingual papillae of various shapes (fusiform, fungiform, goblet), and on this surface there are taste receptors. The tongue has a fixed posterior area and a mobile anterior area that is located on the floor of the mouth.
The intrinsic and extrinsic muscles of the skeleton are fixed on this skeleton. The intrinsic musculature is represented by longitudinal and transversal muscle fibers whose contraction will determine changes in the shape of the tongue.
The extrinsic musculature is formed by muscles that from neighboring structures such as the hyoid bone (hyoglossus muscle), the jaw (genioglossus muscle), the palate (palatoglossus muscle) and the skull (stiloglossus muscle) extend to the tongue, and these muscles are responsible for the movements of the tongue.