Dentists compare dental x-ray radiation with radiation you get everyday. problem is that dental radiation is concentrated to your head.........

No comparison: Dental x-rays do concentrate in the area the beam is pointed, that is true. However the damaging effects of radiation are cumulative. Spending a day at the beach will expose you to more radiation over a larger area of your body than having dental x-rays once a year. A lead apron with a thyroid collar is also used to protect your body when taking dental x-rays. As the cliche goes, apples to oranges