Dental
x-rays
Dental x-rays are a vital tool in the diagnosis of
dental diseases such as cancer, bone infections, abscesses, cysts and
decay. Rays that were able to penetrate
an object revealing the contents within were discovered by Wilheim Roentgen
in 1895.[1]
Radiation is known to be accumulative in the cells
of our bodies. How much radiation do we
as dental consumers get from a regular set of x-rays during a routine dental
visit? This and many more questions
should be asked and understood by each dental care consumer. This article will
address these and other issues that dental consumers should be made aware of.
History
of dental x-rays
Dental x-rays began to be used by Dr..Otto Walkoff in Germany, 1896[2]. The first dental x-ray was used by Dr. Edmund
Kells and in 1856. He used glass plates
to capture the desired image. The first dental x-ray film was used by Dr. Frank
Vanwoert. Dental x-ray equipment and
procedures have progressed over time.
Glass plates, used by Kells in 1856 were changed to film, used by
Vanwoert. Today X-ray film has been
replaced by a digital form reducing almost eliminating exposure to unsafe doses
of dental radiation.
Amount
of radiation from dental x-rays
As
a clinician I am asked a variety of questions regarding the amount of radiation
received from our dental x-rays. X-rays
come from a variety of sources and are accumulative throughout our
lifetime. A unit called a “rem” is used
to measure radiation. A rem is a large unit, much like a mile is a large unit
of length, so we usually use a millirem (mrem) instead, much as you would
measure in inches instead of miles for most purposes. (It takes 1000 mrem to
equal one rem.)[3] A typical dental x-ray image exposes
you to only about 2 or 3 mrem. The National Council on Radiation Protection
(NCRP) says that the average resident of the U.S. receives about 360 mrem every
year from background sources. This comes from outer space, radioactive
materials in the earth, and small amounts of radioactive material in most foods
we consume.3Just for your information, “Some typical sources that may expose you to radiation also include smoke detectors (less than 1 mrem per year), living in a brick house instead of a wood one (about 10 mrem per year due to radioactive materials in the masonry), cooking with natural gas (about 10 mrem per year from radon gas in the natural gas supply), reading a book for 3 hours per day (about 1 mrem per year due to small amounts of radioactive materials in the wood used to make the paper), and even from flying in an airplane (about 5 mrem for one cross-country flight because of the increased altitude.) In fact, you receive about 2 mrem per year from sleeping next to someone! This is because all of us have very small amounts of naturally occurring radioactive materials in our bodies. [4]
Why do I need a Dental X-ray?
At times dental consumers wonder, “x-rays again”. It is important to be aware of the advantages of having regular dental x-rays taken.
Advantages of Dental x-rays
- Digital radiographs reveal small hidden areas of decay
between teeth or below existing restorations (fillings), bone infections,
gum (periodontal) disease, abscesses or cysts, developmental abnormalities
and tumors that cannot be detected with only a visual dental examination.
- Digital radiographs can be viewed instantly on any
computer screen, manipulated to enhance contrast and detail, and
transmitted electronically to specialists without quality loss.
- Early detection and treatment of dental problems can
save time, money and discomfort.[5]
- Digital micro-storage technology allows greater data
storage capacity on small, space-saving drives.
- Dental digital radiographs eliminate chemical
processing and disposal of hazardous wastes and lead foil, thereby
presenting a "greener" and eco-friendly alternative.
- Digital radiographs can be transferred easily to other
dentists with compatible computer technology, or photo printed for
dentists without compatible technology.
- Digital sensors and PSP (photostimulable phosphor)
plates are more sensitive to X-radiation and require 50 to 80 percent less
radiation than film. This technology adheres to the ALARA (As Low As
Reasonably Achievable) principle, which promotes radiation safety.
- Digital radiograph features, including contrasting,
colorizing, 3-D, sharpness, flip, zoom, etc., assist in detection and
interpretation, which in turn assist in diagnosis and patient education.
Digital images of problem areas can be transferred and enhanced on a computer
screen next to the patient's chair.
Are there disadvantages to having routine dental x-rays? There is always a risk involved in taking any type of x-ray especially to the physically compromised however the risk involved with digital dental x-rays outweigh the disadvantages.
Digital dental x-rays are a necessary and vital tool
to the diagnosis and care of dental disease.
Exposure to digital x-rays are now so minimal that even those
individuals that are at risk can safely take care of their dental needs.
Tess Hulet RDH, MHSM
[1] Assmus, Alexi. Early History of x Rays. Summer 1995 P24. www.slac.stanford.edu/pubs/beamline/25/2/25-2-assmus.pdf.
[2] Singer, Steven
R. DDS. The History of OralRadiology Part II. srs2@columbia.edu
[3]
http://www.physics.isu.edu/radinf/dental.htm
