Teeth that are quadrate in form. They have a large occlusal surface.

The fully dentate human adult has three molar teeth in each quadrant, hence a total of 12 molar teeth. The third molar is the most posterior and is also known as the wisdom tooth.

The formation of the first molar is initiated 15 - 17 weeks in utero, begins calcification begins around that time of the birth of the child. Hence any peri-partum disturbances to the health of the baby or mother will result in some disturbance in the formation of the tooth. It may be hypoplastic or hypocalcified when it erupts years later.
The first molar erupts into the oral cavity when the child is about 6 years of age, hence it is also known as the six year old molar. It erupts distal to the most posterior primary tooth.

The formation of the second molar is initated when the child is about 9 months old, calcifies at about 2.5 - 3 years old and erupts at about 12 years old. No surprise that it is also called the 12 year old molar.

The third molar is the most talked about tooth in the head. Its formation is initiated it about 3.5 - 4 years old, and calcification begins at 8 -10 years old. The timing of its appearance in the oral cavity is the most variable of all teeth. Basically, 17 to 82 years old.
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