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07 October 2008

Answer to Question #5840 Submitted to "Ask the Experts"

Category: Medical and Dental Equipment/Shielding — Equipment

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

When taking a digital dental x ray, a sensor is connected to a computer and the computer software processes the captured data and displays the image on the monitor. My questions:

Does the dentist set up the exposure level and time using the computer?
Can the dentist start the x-ray machine using the computer? If yes, what are the safety features to prevent accidental x-ray exposure to the patient?
If a separate button is used to start the machine, is there a cut-off mechanism, or is the x-ray continuously released as long as the button is pushed down?

All exposure techniques are still set on the x-ray machine, whether the image receptor is digital or analog (that is, film).
No, the dentist cannot control the x-ray machine from the computer that receives the image data.
The exposure button on any x-ray machine is typically considered a "dead-man" switch. The exposure can only be initiated and completed by pressing the exposure button, and the exposure can only last for up to the duration of the preset time, no matter how long the button is held down.

Ken "Duke" Lovins, CHP

Answer posted on 16 October 2006. The information and material posted on this Web site is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of 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 specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Web site. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.