In biology and dentistry, a 'Dental Formula' is a simple mathematical way to express the exact arrangement and number of different types of teeth in a mammal's mouth. Human beings are 'Heterodonts', meaning we have differently shaped teeth for different functions.
The very last molars (the 3rd molars) are commonly known as 'Wisdom Teeth'. They usually erupt between the ages of 17 and 25.
Humans are also 'Diphyodonts', meaning we grow exactly two sets of teeth during our lifetime (Milk teeth and Permanent teeth).
Before understanding the formula, you must know the four types of teeth (ICPM):
The formula represents the teeth on exactly one-half of the upper jaw and one-half of the lower jaw.
The Adult Formula is: $\frac{2123}{2123}$
Upper Half Jaw: 2 Incisors, 1 Canine, 2 Premolars, 3 Molars = 8 teeth.
Lower Half Jaw: 2 Incisors, 1 Canine, 2 Premolars, 3 Molars = 8 teeth.
Since this is only half the mouth, you multiply the total (16) by 2.
Total Teeth = 32.
Children have temporary 'deciduous' or milk teeth. They do not have Premolars, and they lack the final set of Molars.
No. While they contain calcium and look like bone, teeth are not bones. The outer layer of a tooth (Enamel) is actually the hardest substance in the human body.
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