One of the most annoying organic alterations is the eruption of the third molar or "wisdom tooth", so called because the age at which it must erupt is around 18 years of age, when humans are supposed to acquire the minimum amount essential of sanity and good judgment.
However, the wisdom tooth itself seems to be the least judicious of all dental pieces. In the first place, it is an inconstant molar that sometimes forms and others, not. When it is formed, it can erupt without problems, but very frequently it causes more or less serious disorders, generally due to the fact that it does not have space to be located at the end of the dental arch.
If the germ of the wisdom tooth has been formed in the right position, it will force a slow and semi-empty exit during which the neighboring structures , such as the mucous gum cap covering it, take a long time to reabsorb and normalize.. In this situation, the gum tab remaining on the crown acts as a valve under which food residues can be retained and infections and mucous lesions develop that can become very painful and seriously complicated.
A consequence of this eruption of the third molar, much discussed by researchers, may be the increase in pressure that is transmitted from tooth to tooth to the anterior region of the incisors and that can cause there the rearrangement of the teeth, stacking them, little by little , some on others.
This phenomenon, however, does not seem to be the exclusive responsibility of the third molar. The displacement of the molars forward (mesialization) is a curious normal movement that occurs throughout life, even in the total absence of moral third parties.
Another type of problem arises if the germ of the wisdom tooth has been formed in a defective position (usually inclined forward in the jaw). This stumbling will easily cause injury to that adjacent molar.
Obviously, this is a complex problem because the surgical extraction of a twisted or included third molar can be quite laborious (especially because the shape of its roots is sometimes decidedly tortuous) and because the repair of the injured second molar entails serious difficulties in a root zone difficult to access, difficult to isolate and difficult to control. We must not neglect, therefore, the surveillance of this conflictive region at the bottom of the oral cavity.
The human jaw has not stopped wane and there are several reasons that explain it. In the first place, the functions that man now exercises with his mouth have varied substantially. Man is no longer required to use it to catch and tear food, nor as a weapon of attack or defense. With the most civilized type of food, very soft and nutritious, you do not need a jaw as "crusher" as before.
On the other hand, the masticatory effort of the jaw during the period of its growth and development has been diminished. The baby in many cases is no longer fed through the breast to the one who bites with his gums to get milk. The change in muscle exercise that is important is important, since the suction of a bottle does not stimulate the relevant mandibular growth.
Now, if the jaw has no choice but to decrease, why the rigorous laws that govern the evolution of the maxillofacial set of man have not been concerned to reduce proportionally the number of teeth? The question remains open, although there is no doubt that there has been enough time for that to happen.