Are large amounts of dental xrays safe?

What is the diffrence between analog and digital dental xray equipment. How much more exposure to radiation will analog equipment cause. Are 18 xrays really necessary for a dental exam. It sure seams like a lot. How many xrays and how often could be considered the minimum to still provide good dental care. Thanks for your time.
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Dental x-rays are the lowest dose radiation exam that are done. Here are some things to consider: On this site, they consider a full mouth series 14 images or x-rays, and this is not on a digital unit, but a traditional film system..... "The exposure rate for a full mouth series is equal to the sum of all the individual exposures or only three millirems. Three millirems are equivalent to about four days of exposure to radiation received naturally from the sun. The overall exposure is actually much less than the sum of the individual X-rays due to the movement of the radiographic tube between exposures to narrow the exposed area to a very small area." AND: 'if a person in an average location in the U.S. were to receive a full-mouth periapical and panoramic examination every 4 months for the rest of their life he would incur only the same risk as a person living in Denver who was not exposed to dental radiography'. http://www.dentalgentlecare.com/x-ray_sa… Remember that x-rays are a highly directed beam of radiation. They do not fly all willy-nilly around the room. The area that is exposed to the radiation is only the area being imaged. "Dental x rays, as with most x rays, are taken with the machine focused right on the area where the x rays need to go. Because of this there is virtually no exposure to anything other than the item of interest (in this case, a tooth or teeth)." http://hps.org/publicinformation/ate/q36…
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