Ambient dose during intraoral radiography with current techniques: Part 1 conversion factor for scattered radiation...

Area of Science:

• Medical Physics
• Radiological Protection
• Dental Imaging

Background:

• Intraoral radiography utilizes rectangular collimators to minimize patient radiation exposure.
• Assessing scattered radiation is crucial for accurate dose monitoring and radiation safety protocols.
• Existing conversion factors may not fully represent scattered radiation in specific intraoral radiography scenarios.

Purpose of the Study:

• To establish a conversion factor for scattered radiation during intraoral radiography using a rectangular collimator.
• To quantify scattered radiation dose in areas outside the primary X-ray beam.
• To provide a more accurate factor for radiation safety assessments in dental settings.

Main Methods:

• Utilized a Rando phantom exposed to various geometries with a Planmeca Intra X-ray unit.
• Measured scattered radiation dose at multiple horizontal and vertical locations.
• Corrected measurements for background and leakage radiation, and weighted them by exposure workload.

Main Results:

• Scattered ambient radiation dose showed even distribution in the horizontal plane.
• Dose in the vertical plane was 20-65% lower compared to the horizontal plane.
• A representative scattered radiation pattern was constructed based on weighted exposures.

Conclusions:

• Established a conversion factor of 0.05 µSv per mAs at 1 meter for scattered ambient radiation.
• This new factor is approximately three times lower than previously reported values.
• The findings contribute to improved radiation safety and dose assessment in intraoral radiography.