Why does my dentist take so many xrays?

The American Dental Association states that the benefits of dental xrays far outweigh the risks.  Especially in this age of digital xrays, radiation levels for dental xrays have plummeted and dental xrays have far less radiation than medical xrays.

http://www.colgate.com/en/us/oc/oral-health/procedures/x-rays/article/ada-07-x-ray-safety