How many teeth grow only once in the life of a human being?

Correct option is B

In humans, teeth are of two types based on how many times they erupt:

1. Deciduous (Milk) teeth – 20 teeth

   • Erupt in childhood and later fall out.

2. Permanent teeth – 32 teeth

   • Replace milk teeth and usually remain for life.

However, some permanent teeth do not replace any milk teeth and erupt only once in life. These are called accessional teeth.

Teeth that grow only once

There are 12 such teeth:

• 4 First molars

• 4 Second molars

• 4 Third molars (Wisdom teeth)

These teeth do not have deciduous predecessors, so they erupt only once in a lifetime.