Dental OSCE (Objective Structured Clinical Examination) Practice Exam

What is the recommended approach to reduce radiation dose in dental imaging?

1. Use higher kV

2. Use lower kV

3. Increase exposure time

4. Decrease the distance of the source

The correct answer is: Use higher kV

Using a higher kilovolt peak (kV) setting in dental imaging is effective in reducing radiation dose. This increase in kV enhances the quality of the X-ray beam, allowing for better penetration through tissues and thereby improving image contrast. As a result, a higher kV setting can lead to a reduction in the amount of exposure time needed to obtain a diagnostic-quality image, which in turn minimizes the overall radiation dose to the patient. Higher kV settings result in a lower patient dose primarily because they generate higher-energy photons that are less likely to be absorbed by the tissues. Consequently, the need for repeat exposures due to inadequate image quality may also be reduced, further contributing to a lower overall radiation exposure. In contrast, lower kV settings may lead to higher patient exposure times while potentially producing images with poorer contrast, which might necessitate retakes and ultimately increase the cumulative dose received by the patient. Similarly, increasing exposure time or decreasing the distance from the radiation source can lead to higher doses being administered, which is counterproductive when trying to reduce radiation exposure.