أَسْنَانُ الإنسان .. كتاب في سبيل موسوعة علمية .. الدكتور أحمد ذكي

Human teeth..

Humans have two natural sets of teeth instead of one set.

The first are called baby teeth.
As for the other, it is with resident teeth.
Likewise, mammals are animals, that is, they have two sets of teeth.

If a person wanted something, he would like to have a third set, because of the speed with which damage comes to the teeth.

What is strange is that teeth quickly deteriorate in a person while he is alive, but then he dies, so the teeth are among the most immortal things in his grave.

Human teeth do not grow after they have fully grown, while we know that rabbits’ incisors continue to grow, and they replace what they consume. The same applies to elephants, and their teeth are only some of their teeth (the incisors), and these teeth grow year after year.

- Baby teeth

Children are born without visible teeth in their mouths, then they begin to appear between the middle of the sixth month and the tenth month, most of them around the middle of the eighth month.

The following table shows the order in which these teeth appear:
The exact date of its appearance was determined by Dr. Harold Stuart.

Order of appearance ------ Date of appearance

Lower central incisors
E, 7 of the months

Upper central incisors
9.5 months

Upper lateral incisors
E, 11 of the months

Lower lateral incisors
13.0 months

Upper first molars
E, 15 of the months

Lower first molars
16.0 months

Upper canines 19.0 months


Lower canines, 0-19 months

Lower fixed front molars
0, 26 months

Fixed upper front molars
0, 27 months

So, the number of baby teeth is only 20

- Artificial teeth

Perhaps the first thing a person asks about is the matter of teeth
Its sources are synthetic.
It is funny that it is mentioned that George Washington, the first president of the United States, made an artificial suit for him from the ivory of the huge animal called the seahorse or sea buffalo, Hippopotamus, and despite this, it was not a comfortable suit for him.

The Battle of Waterloo took its tomb for many years
Sources for artificial teeth.

24 years after the Waterloo incident, Charles Vulcanising Goodyear discovered a way to harden Goodyear rubber, so artificial teeth were made from this rubber, making them easier to form and placing them in the mouth more closely.

Today, artificial teeth are made of plastics
(Plastic), and from Chinese Porcelain, which is made especially for this. About a fifth of the teeth are Chinese. The manufactured denture is missing a wisdom tooth on each of its four sides, due to space constraints

Today, the manufactured denture has an acceptable shape to the skilled maker, and it has become comfortable, but it lacks the pressure when chewing and biting that natural teeth permit. Nature permits a pressure of between 150 and 250 pounds, while artificial ones permit no more than between 10 and 30 pounds.

(The molar is a crown, which is what appears above the gum.
The molar is a root, which is hidden under the gum.
⏺Enamel is the material that covers the crown and is the hardest thing in the human body. 96 percent of its composition is mineral.
⏺Dentine, or teeth, is what makes up the interior of the crown, as well as most of the root. It is similar to bone, and 70 percent of its composition is mineral.
The developing tooth consists mostly of enamel and dentin.
⏺In the middle of the dentin is the pulp of the tooth, and it contains blood vessels and nerves.
⏺Tooth cementum, which is a substance that covers the root above the dentin.
⏺ Between this cementum and the jawbone in which the tooth rests, there is a rigid, connecting membrane that connects the root of the tooth to the jawbone, and it is known as the periradicular membrane.
Peridental membrane.