Synonyms
Latin : Os, Oris Greek : Stoma English : Mouth
Definition
The mouth is a body cavity, which is responsible not only for the intake of food but also for the formation of the voice. It forms the upper part of the human digestive tract.
Anatomy
The mouth is limited by several structures. The anterior boundary is formed by the lips (labia oris) and the posterior boundary is formed by the narrowing of the throat (isthmus faucium). The palate (palatum) and the base of the mouth (diaphragm oris) form a boundary both above and below.
The lateral border is formed by the cheeks (buccae). The space surrounded by these structures is called the oral cavity (cavum oris). It is divided into the oral vestibule (Vestibulum oris), the main cavity (Cavitas oris propria) and the pharyngeal or pharyngeal narrowing (Isthmus faucium).
The oral vestibule is the area between cheeks, lips and teeth. The lips form the entrance to the oral cavity. The excretory ducts of some salivary glands, such as those of the parotid gland (Glandula parotidea), as well as those of the smaller salivary glands (Glandulae labiales and Glandulae buccales), open into the oral vestibule.
The main cavity contains the tongue and teeth, which serve to reduce the amount of food ingested. The function of the human oral cavity is to absorb food and prepare it for subsequent digestion. The mouth is lined by a special mucous membrane consisting of a multi-layered squamous epithelium. This multi-layered squamous epithelium is mostly keratinized, but partly also un-keratinized.
Microbiology
The human mouth is populated by many different germs. The entirety of microorganisms that accumulate in the mouth is called oral flora. It is a community of microorganisms that play a role in the digestive processes and in the body’s immune defense.
Various bacteria and fungi form the largest part. The composition of the physiological oral mucosa includes actinomycetes, lactobacilli, neisseria and streptococci. A distinction is made between microorganisms that always colonize the mouth (resident oral flora) and those that are only there temporarily (transient oral flora).
Some bacteria can be responsible for the occurrence of caries. The most common representative of cariogenic germs is Streptococcus mutans. Other bacteria can cause inflammation of the mucous membranes or even inflammation of the gums (periodontitis).
The microorganisms also play a major role in the development of bad breath. The tongue has a large, very rough surface structure, on which germs can deposit particularly well. The bacteria decompose the food left behind there and form a bad, sulphurous odour, which we call bad breath.
