Human teeth are generally 28-32 pieces, the number of these four activities is to prepare the wisdom teeth. In fact, just the name of wisdom teeth is very important, but also than the "incisors" "fangs" "after molar" nice, but the fact that most of the time in order to disrupt the mouth "bad elements."
What is the wisdom teeth
Wisdom teeth are within the human oral cavity, alveolar bone innermost third molars, is the latest eruption of molars, usually a total of four, symmetrical up and down, but there are also large differences in the crowd, and some less than four or no more than a handful will be four. Because of its eruption very late, usually at 16 to 25-year-old eruption, this time the people's physical and psychological development close to the ripe, is seen as the "wisdom of the arrival of" a symbol, it is called "wisdom."
What is the function of wisdom
Wisdom teeth just an ordinary, middle pulp in addition to blood vessels, connective tissue, and only from the inferior alveolar nerve branches. Tooth nerve is contained in the pulp of the inferior alveolar nerve endings, the inferior alveolar nerve from the mandibular nerve, the trigeminal nerve branches. Although the trigeminal nerve is a cranial nerve, but its main function is in charge of facial pain and temperature tactile feel and control chewing movement, with no relationship between intelligence and memory.
Wisdom of the "evolution" of development
Observation of ancient human or other primate jaw, can easily find their jawbone and modern compared to the larger, wider width tongue cheek, near and far longer to length. As a mandibular space is very abundant, currently can be seen on ancient human skull fossil, growth direction and occlusion wisdom teeth are generally more normal, modern impacted wisdom teeth is rarely the case, indicating that the jaw provided space with state of eruption of wisdom teeth have a direct relationship.
When humans began to understand the use of fire, after making master tool, the food is also conscious development of animal husbandry and the cultivation of mankind to prepare the digestive system more suited to their stable food source, making the food more and more sophisticated, human It is no longer necessary now that ancient human Australopithecus and powerful jaws to provide a less powerful bite force and grinding food area, the role of wisdom teeth in chewing and digestion also gradually weakened. At the same time in this evolutionary process, humans need more brain capacity to complete more complex mental activity, therefore, a strong jaw no longer an important factor affecting the survival of mankind, is the evolution of a larger brain capacity direction. After generations of natural selection, the human brain capacity is increased, reducing the width of the jaw, shorten the length to reduce the strength of the entire jaw.
In modern space due to changes in the jaw, human mandible can supply the eruption of teeth has been greatly reduced, so that at the time of eruption of wisdom teeth often because of lack of space caused by ectopic eruption, impaction. Difficult eruption often leads to excruciating pain, or cause pericoronitis. Finally, even if some of the eruption, but because of the position deviation, can not form a stable and effective occlusion of (occlusal) teeth can not chew.
So wisdom is actually the biological traits of human evolution has been abandoned due to different individual genes in the expression of this trait is different. Currently this evolutionary process has not ended, although some people's wisdom tooth is gone, but most people have a wisdom tooth germ was born, but there will be varying degrees of difficulty when the eruption, only a few people can successfully wisdom teeth eruption, and build good relations exercise occlusal function. But in the end wisdom will be like the tail as in humans disappear.
What kind of wisdom teeth should be pulled out
Although the ability to chew wisdom contribution to modern in terms of survival is not required, but if the normal eruption of wisdom teeth, bite and establish relations, or at least will not bring pain and risk of infection and affect other teeth, it is not removal of. On oral clinical operations, indications for wisdom tooth extraction, there are very strict rules, only in the event of the following occurs, it will consider removal of wisdom teeth:
1. caries: If the wisdom tooth decay, occlusal surface is not deep cavities can fill, but need a good abutment surface tooth decay dental technology, and its fillings, it is better to unplug. Wisdom tooth decay deep need root canal treatment, also recommended removal.
2. diseases caused by adjacent teeth: dental patient adjacent lesions usually do not feel, mostly by the dentist to X-ray diagnostic discovery. This is due to lack of space for eruption of wisdom teeth, impacted ectopic leaning on the second molar, the second molar caused by cleaning is not easy, even second molars partially absorbed phenomenon can cause severe discomfort or pain.
3. The lack of space caused by the crown peripheral inflammation: This is getting smaller and smaller because the arch, when the eruption of wisdom teeth patients have swelling and pain. To prevent this from happening again, it is recommended removal as soon as possible after the inflammation subsided.
4. Local clean difficult: due to lack of spatial relationships, wisdom teeth usually malposition, so often cause difficulties to clean teeth, prone to tooth decay phenomenon.
5. None of the teeth: If the opposite of wisdom teeth wisdom teeth do not compete on the bite to it, sometimes wisdom teeth occur over germination elongation phenomenon, thereby affecting the bite, it should pull wisdom teeth.
6. impacted wisdom teeth: This is usually the most troublesome one. This type of teeth, usually buried in the inside of the alveolar bone, when if inflammation or diagnose lesions have occurred frequently, you must unplug.
7. cause other diseases: If wisdom teeth caused by cysts or tumors, we need to unplug.
8. Orthodontic need: To ensure the effectiveness of orthodontic treatment, usually to pull wisdom teeth.
9. blocking suspicious because of unexplained etiology who neuralgia, or suspected lesions of teeth when, should be removed.
Also to note that mandible wisdom teeth are fully formed only after the eruption, if removed, no effect on the face-lift.
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