No abstract

No abstract

Operator exposure to backscatter radiation while using an Aribex NOMAD radiation emitting device (a portable, self-contained, cordless, hand-held dental X-ray unit) was determined while the operator employed various typical and atypical use scenarios during the exposure of 715 digital and/or film-based dental radiographs and 200 study control exposures. Study data was compared to the radiation safety occupational exposure annual Maximum Permissive Dose (MPD) of 50 mSv (5000 mrem) to determine the possible exposure risk to an unprotected operator using this device. The results showed the reproductive organs received the highest dose and the thyroid the least. The average operator whole body dose for the study was determined to be 0.047 mSv (4.47 mrem) or 0.09% of the annual MPD. Extrapolating the data as an expression of averaged annual operator exposure resulted in a whole body dose of 0.4536 mSv (45.36 mrem) or 0.9% of the annual MPD, These results are well below established occupation exposure limits and are compatible with those published by the manufacturer.

No abstract

Clinical experience indicates that newly available portable hand-held x-ray units provide advantages compared to traditional fixed properly installed and operated x-ray units in dental radiography. However, concern that hand-held x-ray units produce higher operator doses than fixed x-ray units has caused regulatory agencies to mandate requirements for use of hand-held units that go beyond those recommended by the manufacturer and can discourage the use of this technology. To assess the need for additional requirements, a hand-held x-ray unit and a pair of manikins were used to measure the dose to a simulated operator under two conditions: exposures made according to the manufacturer's recommendations and exposures made according to manufacturer's recommendation except for the removal of the x-ray unit's protective backscatter shield. Dose to the simulated operator was determined using an array of personal dosimeters and a pair of pressurized ion chambers. The results indicate that the dose to an operator of this equipment will be less than 0.6 mSv y⁻¹ if the device is used according to the manufacturer's recommendations. This suggests that doses to properly trained operators of well-designed, hand-held dental x-ray units will be below 1.0 mSv y⁻¹ (2% of the annual occupational dose limit) even if additional no additional operational requirements are established by regulatory agencies. This level of annual dose is similar to those reported as typical dental personnel using fixed x-ray units and appears to satisfy the ALARA principal for this class of occupational exposures.