Radiation, Bananas & Dental X-rays

You may have noticed something new on the walls of our treatment rooms:  a Radiation Dosage Chart.  This (hopefully) easy to read list is meant to give you a comparison of the amount of radiation you receive from various sources.  The unit of measurement is milli Sieverts.  Point of reference:  Americans typically receive 3 milli Sieverts of background radiation per year.

Notice some of the items listed:  sleeping next to someone, chest x-ray, dental x-ray, eating a banana?!?  Turns out there is an unofficial comparison of radiation dosage called the “Banana Equivalent Dose” or BED.  The humble yellow fruit has a small – micro – amount of radiation because it contains potassium, 0.1 micro Sievert, to be exact.

The purpose of the BED is not to keep you from enjoying your bananas; it hopefully puts into perspective the radiation dosage you get from ordinary living, and, most importantly to our purposes, dental x-rays.  

Take note where those dental x-rays fall on that list:  not too far below the banana, at .005 milli Sieverts.  Of course that’s just one x-ray; the full set of x-rays, which in our office is done around every 5 years, comes in at .06 -.07 milli Sieverts.  This is still far less radiation exposure than any of the medical x-rays listed. 

Guess if you really, really like bananas, you could eat about 600 of them and then you might want to skip your dental x-rays.  But I wouldn’t suggest doing that, because sometimes there are hidden problems with your teeth that we can’t see just by looking in your mouth.