Small amounts of radiation are used to make pictures of teeth (radiographs).  These black and white images show various shades of grey because some portions of teeth or dental restorations let more or less of the radiation pass through. The result is a radiograph that shows to a moderate level the presence of dental decay.  It is nearly impossible to diagnose the presence of decay between teeth without using dental radiographs.  By using radiographs, small areas of decay can be indentified before the decay process endangers the life of the tooth.

Some people are afraid of the radiation used in dentistry.  Dental radiographs use a very small amount of radiation and it is directed exactly to the site where it is needed.  The amount of radiation required for one dental radiograph (bitewing or periapical) requires about the same amount of radiation as you recieve by standing in a parking lot in the sun for a few minutes, or riding in an airliner for a few minutes.  In other words, the fear of dental radiographs, which are used with caution and good judgement, is totally unfounded.  The minimal radiation risk present in dental radiographs is far outweighed by the diagnostic advantage provided by the radiographs.