Comparative Radiation Doses:

Dental X-ray is equivalent to half a day of normal background radiation.

One air flight cross-country exposes you to the equivalent of eight dental x-rays.

Chest X-ray        0.05 mSv

Mammogram       0.70 mSv

Cardiac Cath       7.00 mSv

Chest CAT scan 10.00 mSV 

Dental X-rays     0.005 mSv