Radiation isoexposure curves about a dental chair during radiography

Blackening of unprotected dental X‐ray films due to scattered radiation

“…Blackening of films positioned anterior to the phantom head was higher than for films positioned lateral to the head. This observation is in accordance with previous findings that scattered radiation generally extends more in an anterior direction than lateral to and behind the patient (4)(5)(6). It also corresponds well with the recommendations for the operator to be positioned lateral to and behind the patient if possible (8).…”

“…originate from scattered,, transmitted, and/ Previous studies have revealed amounts of or leakage radiation (in the following abbre-scattered radiation originating from single viated to "scattered radiation"). Corre-exposures of i s using pointed cones ranging spondingly, exposed films awaiting proces-from approximately 0.05 to 0.15 mR (4)(5)(6) sing may be subjected to additional irradia-at distances of 1-2 m. It has also been shown tion from subsequent exposures. that replacing tbe pointed cone with open-In textbooks of radiology it is generally ended or lead-lined cones reduces the recommended to avoid unintended exposure amount of radiation (5,6).…”

Ambient dose during intraoral radiography with current techniques: Part 1 conversion factor for scattered radiation using a rectangular collimator

“…Two published reports from 1959 and 1968 have provided data on ambient radiation doses at different operator positions around the dental chair during intraoral radiography. 2,3 Although the materials and the methods described in those papers do not correspond to current radiological practice (type of cone, focus-toskin distance, and units are out of date; and the 'permissible dose' is now obsolete), these papers clearly show that the scattered radiation dose is highest anterior to the patient's head.…”

Ambient dose during intra-oral radiography with current techniques: Part 2 quantifying the remnant beam - an in vivo study

“…Earlier investigations found that a higher dose prevails in the remnant beam than in areas where only scattered radiation is present. [4][5][6] One limitation of these studies is that they used phantoms to determine the dose in the remnant beam. The phantoms consisted of a human skull covered with tissue-equivalent material that interacted with radiation from the dental X-ray device in manner similar to that of the head of a living patient in the dental chair.…”