Radiography

Every dental hygienist knows that the “as low as reasonably achievable” (ALARA) principle is an important concept in radiation safety. The overriding principle behind reducing radiation risk for our patients is to use techniques that limit radiation exposure.¹ Many methods exist to keep the radiation dose for our patients as low as reasonably achievable, but one of the best ways to accomplish this is to use digital imaging.

Conventional film-based radiography is safe for the patient. In the past, each time a new speed of film was introduced, a corresponding drop in the exposure time for the patient was seen. However, digital imaging conforms to the ALARA Principle by minimizing radiation exposure by all reasonable means. Less x-radiation is necessary to form a digital image on the receptor because the receptor is more sensitive to x-rays than traditional film. Exposure times are 50% to 80% less than those required for conventional E-speed film.

As is the case with any new technology, digital imaging had some issues when it was first introduced to dentistry in 1987. Resolution of the image was somewhat problematic in the early stages, thus diagnosing important findings such as interproximal caries and periapical pathology seemed to be better accomplished with traditional film. The cost of installation of a complete digital system was considerable. Early imaging receptors were thicker and bulkier than conventional film, making it somewhat uncomfortable for the patient. Other types of sensors could not withstand heat sterilization, therefore, infection control was another factor to be considered. However, the technology has quickly improved.

THE BENEFITS

Advantages of digital imaging include: lower radiation dose to the patient; immediate availability of images; no chemical processing required; image enhancement possibilities via computer features; simple image storage and retrieval; promotes communication with patients, colleagues, and insurance companies; and is an effective patient education tool.²

In addition to using digital imaging, various techniques are available to reduce the amount of radiation received by our patients during dental radiographic procedures. The American Dental Association Council on Scientific Affairs advocates the ALARA Principle and recommends completing a thorough health history and oral examination prior to ordering radiographs, using the fastest image receptor possible, collimating the x-ray beam, avoiding unnecessary radiation exposure, and using protective leaded aprons and thyroid collars when they will not interfere with the primary beam.

Some dental professionals may feel that no change is necessary. However, digital imaging enhances the way patients view the dental office as practitioners provide the best diagnostic treatment available. Since computers play a large role in most dental practices today with the scheduling of appointments, billing functions, and chart information, digital imaging will eventually be widely incorporated. Dental personnel who have made the switch to digital imaging find it is a valuable tool, very state-of-the-art, creates time efficiency with rapid image viewing, and serves as a wonderful patient education resource.

The decision of which is better for your dental practice—digital imaging or traditional film—may be a difficult one to make. But remember the ALARA Principle and keep your exposures as low as reasonably achievable.

REFERENCES

1. ADA Council on Scientific Affairs. An update on radiographic practices: information and recommendations.ADA Council on Scientific Affairs. J Am Dent Assoc. 2001;132:234-238.
2. Haring JI, Howerton LJ. Digital radiography. In: Dental Radiography: Principles and Techniques. 3rd ed. St Louis: Elsevier Health Sciences; 2006:343-354.
3. Bartolazo EJ. Digital radiography: a change for the better. Dental Equipment and Materials. 2006;11(3):23-24.
4. Berthold M. ALARA principle reduces radiation exposure. Available at: www.ada.org/prof/resources/pubs/adanews/adanewsarticle.asp?articleid=854. Accessed August 23, 2006.
5. White SC, Pharoah MJ. Digital imaging. In: Oral Radiology Principles and Interpretation. 5th ed. St Louis: Mosby; 2004:225-244.

From Dimensions of Dental Hygiene. September 2006;4(9): 30.