How many different teeth do children have?

Depends. The number of teeth children have depends on the age of the child, stage of development and whether or not any primary teeth are lost or retained. Generally, there are 20 primary or baby teeth and 32 permanent teeth. A child may be in a mixed dentition state where they have a combination of primary and permanent teeth.
Different teeth? Children up to approx age 5 usually have 20 teeth when all of their baby teeth are in. Adults over 17 usually have 28 and 32 if you count the wisdom teeth. Between the ages of 5-12 on the average, children are losing their baby teeth and getting their adult teeth. Children have 4 incisors, 2 canines and 4 molars on each arch totally 20. Adults have4 incisors 2 canines and 4 premolars 4-6 molars @.
Depends on age. By age 3 all 20 baby teeth have erupted. At about 6 the 1st permanent molars erupt making 24. Between 6 and 12 the 20 baby teeth fall out and 20 permanent teeth replace them. At 12 the 2nd molars erupt making 28. In late teens wisdom teeth erupt making 32. If you have concerns go now to dentist, pediatric dentist, or orthodontist to evaluate dentition all development.