Instantaneous dose rate of scatter radiation in dental radiography
S.D. Tabakov 1 , P.P. Nixon 2 , N.J.D. Smith 3
1. Department of Medical
Enginearing and Physics, King’s College London – GKTSM,
London SE5 9RS (UK)
2. Department of
Dental Radiology, University of Sheffield, Sheffield S10, 2SZ
(UK)
3. Dental Institute,
King’s College London, London SE5 9RS (UK)
Manuscript received: March 12, 1999; revised: September 10, 1999.
Accepted for publication: November 9, 1999.
Abstract
The study reports the results of an investigation of the instantaneous dose rate (during the time of the exposure) of scatter radiation in dental radiography. Four different dental intra-oral X-ray units have been assessed. Radial diagrams of the scatter radiation dose rate at 2 metres from the centre of the patients’ head are shown for the assessed X-ray units. In general the scatter radiation distribution around the patient for all four X-ray units has a similar pattern. The maximum is in the area opposite the patient’s face (45 0 to 135 0 from the primary beam) – between 250 - 450 m Svh -1 , and minimum behind the X-ray tube – of the order of 60 m Svh -1 – the safest place for the staff performing the exposure. This significant variation of the scatter radiation around intra-oral dental X-ray units should be taken into consideration when planning dental rooms with X-ray equipment.
KEYWORDS: Scatter Radiation, Instantaneous Dose Rate, Dental Radiography, Dose.