Answer to Question #12492 Submitted to "Ask the Experts"

Category: Medical and Dental Patient Issues — Dental

The following question was answered by an expert in the appropriate field:


Can the technicians make mistakes that would increase the radiation coming out of the machine? I had a panoramic dental x ray and she said she had never used this new one before, it kept turning off, but eventually she got it going. Could she have over-exposed me by increasing the radiation from the computer? Can x rays generate a dangerous amount of radiation from malfunctioning or human error, or are there preset limits on machines?


In general, it is usually possible to set an x-ray unit to technique settings that are too high or too low for the image that is needed, but it is unlikely. Modern x-ray equipment is designed to have preset technique factors for different exams and patient sizes, which is how the x-ray operator will typically use a machine. It is often possible to set an x-ray unit to manual mode to adjust technique factors, but for patient studies there is normally little reason to do this.

If the operator commented that they have not used that equipment before, they should not be operating the unit unless they have been trained on that type of unit (manufacturer and model specific). Your comments about the unit stopping and starting repeatedly may just have to do with the operator not knowing how to properly operate the unit related to the motion of the unit and not necessarily the x-ray technique settings. Note that panoral x-ray units typically have a full rotation to return to a "start" position that does not use x ray.

I recommend that you share your concerns with your dentist. He or she may be able to explain to you what happened in this case or may realize that additional operator training is necessary.

It is unlikely that you were exposed to amounts of radiation that would be of concern, however, if you did receive multiple unnecessary x rays, your dentist should have access to a qualified radiation expert (i.e., a medical or health physicist) who can perform a radiation dose calculation if they consider it necessary.

Kennith "Duke" Lovins, CHP

Answer posted on 22 May 2018. The information posted on this web page is intended as general reference information only. Specific facts and circumstances may affect the applicability of concepts, materials, and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice. To the best of our knowledge, answers are correct at the time they are posted. Be advised that over time, requirements could change, new data could be made available, and Internet links could change, affecting the correctness of the answers. Answers are the professional opinions of the expert responding to each question; they do not necessarily represent the position of the Health Physics Society.