Question

Primary dentition in humans differs from permanent dentition in not having one of the following teeth

• A. Canines
• B. Pre-molars
• C. Molars
• D. Incisors

Answer 1

The correct option is B Pre-molars

• Human beings have two sets of teeth during their life, i.e, one temporary set and another one permanent set.
• A set of temporary milk or deciduous teeth is replaced by a set of permanent or adult teeth. Such type of dentition is called diphyodont.
• Milk teeth are 20 in numbers. Their dental formula is $\frac{2102}{2102}$. This means 2 incisors, 1 canine, 0 pre-molar, 2 molars. (on one side of the upper/lower jaw.)
• Adult teeth are 32 in numbers. Their dental formula is $\frac{2123}{2123}$. This means 2 incisors, 1 canine, 2 premolars, 3 molars. (on one side of the upper/lower jaw.)
• Hence, Pre-molars are not present in the primary dentition.
• Therefore, Option B is correct.