What's in human lips

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The mouth is the entrance gate for everything edible and drinkable. It is the uppermost part of the digestive tract, where chemical digestion is already initiated. With the help of the teeth and tongue, the supplied food is chopped up and mixed with saliva to form a lubricious paste, which is then transported through the swallowing process into the throat and further into the esophagus. In addition, the mouth is important for voice production, breathing and expressing emotions (facial expressions). Read everything you need to know about your mouth!

What is the mouth

The mouth (Latin: Os) is the upper opening of the digestive tract, in which the food is divided and processed into a slurry that can be slipped and swallowed. He is also involved in voice training, facial expressions and breathing.

The oral cavity (Cavitas oris) extends from the crack in the mouth (which is enclosed by the lips) to the throat (the exit to the throat). The palate forms the roof of the oral cavity, the floor of the mouth its lower end. The cheeks represent the lateral boundaries. Inside the oral cavity are the two rows of teeth and the tongue. The gap-shaped space between the lips and the closed rows of teeth is called the oral cavity.

What is the function of the mouth?

The mouth fulfills various functions:


The job of the mouth, together with the lips, is to take in food. The teeth, in cooperation with the masticatory muscles, ensure that the food ingested is bitten off and broken up. The incisors and canines have the task of dividing the food, the molars the task of crushing it and mixing it with the saliva (saliva) to a pulp. The muscular tongue supports the process.

Enzymes contained in saliva (such as amylase) start the chemical digestion of carbohydrates while chewing. Millions of microorganisms contained in saliva (oral flora), along with germs in the spaces between the teeth, on the tongue and on the mucous membrane, participate in digestion. The taste buds, which are mainly distributed on the tongue, perceive the taste of the food as soon as they come into contact with the flavors of the food dissolved in the saliva.

The saliva is produced by various salivary glands, especially the paired parotid glands, mandibular salivary glands and sublingual salivary glands. The saliva is released partly continuously, partly reflexively - for example, the smell of food, chewing movements and touch stimuli during the dentist's visit can lead to increased saliva being secreted.

In addition to digestion, saliva has other functions. For example, it protects the oral mucosa from drying out. It's also antibacterial. Last but not least, the saliva with its various ingredients (such as bicarbonate) ensures that the predominant acid content (pH value) remains almost in the neutral range. This is very important: if the milieu is too basic for a long time, tartar builds up faster. If it is too acidic for a long time, the enamel becomes thinner.

Voice training and facial expressions

Another important function of the mouth is as a resonance organ that is involved in the formation of the voice. Due to the great malleability of the palate, tongue and lips, language can be articulated and tones can be changed.

The facial muscles around the mouth, together with the lips, can express feelings. But it is also vital for the baby, who has to close their lips airtight around the mother's nipple or the teat of the milk bottle in order to be able to generate the negative pressure in the oral cavity that is necessary for sucking.

Where is the mouth located?

In all mammals - including humans - the mouth is located in the head and represents the upper end of the digestive tract. In the rear area is the transition to the pharynx, which merges into the esophagus and trachea.

What problems can the mouth cause?

Numerous health problems can occur in the mouth that are related to the lining, teeth, gums and / or lips. Aphthae - painful, small inflammations - are particularly common. They can affect the gums, oral cavity, tonsils and also the tongue. If the immune system is weakened, a fungal infection of the mucous membrane caused by Candida species develops. The medical term for this is candidiasis (candidiasis). Herpes simplex viruses can cause cold sores ("fever blisters") on the lips - painful, itchy blisters. The herpes viruses attack the mucous membrane in the mouth, doctors speak of the so-called mouth rot.

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