Introduction - Nomenclature

Lec.1 Dr. Ghassan Ali
Introduction
Nomenclature
Dense = tooth
Dental = anything related to teeth
The jaws:
The jaw is the bone which carries the teeth. There are two jaws:
1. the upper jaw which is fixed and is called (( the maxilla)).
2. The lower jaw which is movable and called (( the mandible)).

The deciduous Teeth
Usually, at birth there are no teeth in the mouth, but many teeth in various stages of development are found in the jaws.( some time newborn come with neonatal teeth)
After birth, the eruption of deciduous teeth starts at the age of 6±3 months and lasts until 2.5-3 yrs. of age.
The deciduous teeth stay until the permanent teeth erupt at about 6 years of age, when the transition to the permanent dentition begins.
The deciduous teeth are 20 in number, they have the following formula for each side:
I ? C ? M ? =10
2 upper incisors (central and lateral).
2 lower incisors (central and lateral).
1 upper canine.
1 lower canine.
2 upper molars.
2 lower molars.

The permanent teeth:
The transition to permanent teeth begins with the emergence and eruption of the first permanent molars at the age of six years, followed by shedding of the deciduous teeth and emergence and eruption of the remaining permanent teeth.
The process requires about 20 years to complete. The number of permanent teeth including third molars are 32. They have the following formula for each side:

I ? C ? P ? M ? =16

2 upper incisors (central and lateral).
2 lower incisors (central and lateral).
1 upper canine.
1 lower canine.
2 upper premolars.
2 lower premolars.
3 upper molars.
3 lower molars.

Anterior and posterior teeth:
Teeth are grouped into:
1. Anterior teeth which includes incisors and canines.
2. Posterior teeth which includes premolars and molars.