Interesting facts about X-rays

The first dental X-rays were made in the same year they were discovered�1895. We have seen the huge, radiation-scattering dental X-ray machines evolve to smaller, safer, faster, and better equipment.

Dave Cheney

The first dental X-rays were made in the same year they were discovered - 1895. We have seen the huge, radiation-scattering dental X-ray machines evolve to smaller, safer, faster, and better equipment.

Now, digital radiography is ushering in even greater things for us. As more manufacturers enter the field - offering new and better ideas - digital radiography is quickly becoming accepted by dental and medical offices as an answer to many problems. Soon film, processors, chemicals, and darkrooms will be obsolete. Digital radiography requires less than 10 percent of the radiation as film units, and the results are many times more useful to the practitioner and peripheral industries in the dental and medical fields.

We know that radiation can be harmful to human beings. Dental X-ray machines produce radiation in very small doses and are not thought to be a significant risk to the patient or staff personnel. Even those of us in the business of testing and repairing radiation producers have experienced only insignificant amounts of exposure, despite being in much closer proximity to the machines as we repair or calibrate them. However, the absence of conclusive proof of whether there is danger or not requires us to practice radiation safety.

Every manual on radiation safety stresses the ALARA (As Low As Reasonably Achievable) principle - i.e., any dose that can be reduced without major difficulty, great expense, or inconvenience, should be reduced or eliminated. This extends not only to your X-ray machine, but to your processor and darkroom as well. If the processor is not performing efficiently - or the darkroom has light leaks which inhibit the production of a diagnostic quality film - another image may be needed, requiring more radiation exposure to the patient.

How much radiation am I getting?

There is radiation in the air we breathe, in stone, bricks and cement, in luminous watch dials, in our color television sets and, yes, in our computer screens. None of the exposure from these sources is enough to do harm, but when added to the exposure from industrial and medical sources, it all adds up and provides a good reason to adhere to safety guidelines. Exposure from dental X-ray machines is minimal and should not be feared if simple precautions are practiced:

Do not stay in line of the beam during exposure.

Do not stay and hold the X-ray head or the film while the X-ray is being activated.

Radiation safety programs

Most governing bodies require a viable radiation safety program be in place in the dental office. Even if not required in your area, it is practical to have such a program. During a staff meeting, some words regarding radiation safety would be prudent and appreciated. You could assign a staff member to gather and share this information. Some good sources of information are the Eastman Kodak Company, your state dental society, or your local dental dealer. Whatever you do, keep records of any safety meeting, and have each staff member attending sign a form noting he or she has had this training. People fear things that they don’t understand. Information and education dispels fear.

Check machines regularly

It is extremely important to have your machines checked regularly. Some machines overradiate the patient; some are not radiating enough. Some are out of calibration in such a way that it is harmful to the machine itself. Have your service technicians come by periodically and calibrate your machines to manufacturer’s specifications using noninvasive or traditional meters. They should also look at your darkroom and processor for any area of concern that might need some attention to provide your patients with better and safer radiographs.

Dave Cheney is a retired service technician from Patterson Dental with over 30 years in the dental industry. He is the author of “Doctor, Did You Check the Breaker, Too?” a manual written to assist the dental staff in analyzing and performing minor equipment repairs when a technician is not warranted or not readily available. To order the manual as a book or CD, call (800) 695-0943. You may also order it online through his Web site at

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