Computed Tomography (CT) scanners provide doctors and dentists with detailed 3D images of an individualís anatomy. They can provide physicians with information about the patientís condition that would be difficult if not impossible to obtain by other methods such as regular X-rays and standard visual examinations. The radiation emitted by these CT scanners, however, restricts their use for safety reasons, especially in susceptible individuals such as children.
However, the convenience of cone-beam CT scanners in dentist offices has often overridden the more important concern for the patientís well-being. Although the manufacturers of these scanners have promoted these scanners as safe for use in everyday dental practice, there have been few independent studies validating the safety of these devices.
Despite the significantly higher doses of radiation emitted by these scanners when compared with traditional imaging systems, some dentists use the cone-beam CT scanners for screening all patients, even children; this despite a joint statement by the American Association of Endodontists that said that cone-beam CT scanners "must not be used routinely for endodontic diagnosis or for screening purposes in the absence of clinical signs and symptoms." The AAE also goes on to that state that patients should be informed of the "significant risk, benefits and alternatives."
Much of the enthusiasm for using cone-beam CT scans has come from the misinformation on their safety and effectiveness, with manufacturers sponsoring dentists to promote the sale of the scanners. Even The Journal of the American Dental Association devoted an entire issue to cone-beam technology, an issue that was sponsored by Imaging Sciences International (a leading manufacturer of cone-beam scanners).
There are alternatives to the radiation-emitting cone-beam CT scans. SureSmile, a device that uses a robot to bend wires to move teeth into place, uses 3D images as guides. These images can be taken with tiny cameras using no radiation or can be taken with a cone-beam CT scanner. Although the use of cameras can be somewhat more cumbersome, the lack of any radiation exposure makes them a safer alternative, especially for younger patients.
However, these safer methods are often more cumbersome, require more time and are uncomfortable for patients, especially younger ones who are already nervous.
Radiation-emitting scanners and other radiological devices used in medicine and dentistry are often lightly regulated, with some countries and states having almost no inspections of dental X-ray devices. The overall risk of radiation to the patientís organs is often not assessed during inspections and the practicing dentistís understanding and operation of the scanners is, for the most part, not evaluated on a consistent and uniform basis.
A number of prominent physicians have criticized the aggressive marketing of cone-beam scanners. Dr. Christos Angelopoulos, director of the division of oral and maxillofacial radiography at the Columbia University College of Dental Medicines, states that radiation levels can vary significantly from one scanner to the other and from one setting to the other. Dr. Angelopoulos cautions against the routine use of the scans stating that "[the frequent use] gives the feeling to the patient that [the scan] is not risky at all, whereas thatís wrong."
Often times, the dentist yields not to the pressure of convenience but to the threat of litigation. Arthur W. Curley, a lawyer in California who has received speaking fees from Imaging Sciences, states that "Negligence may be the failure to incorporate new technologies that meet well-defined legal standards."
According to the AAE, dentist office staff are also at risk from the radiation emitted from cone-beam CT scanners, radiation that is higher than that produced by conventional radiography. The association states that extra safety measures need to be taken for these personnel, and that qualified experts should be consulted before and after the installation of these scanners in order to comply with state and federal regulations.
In the rush to make the trip to the dentist less uncomfortable, more exact and less laborious, both for the patient and the dentist, manufacturers of cone-beam CT scanners may have put the general health of the public at risk. The increased radiation, overenthusiastic marketing, deficient training and limited regulation and testing currently in place with these scanners have created a situation where the convenience has pushed aside the importance of safety.