The Case For Digital Radiography
How today's systems tip the balance in favor of going digital
Innovation and change are inherent in dentistry, and nowhere is this more evident than the ever-evolving landscape of dental radiography. Used to identify or confirm the extent of disease, plan treatments, and educate patients about their oral health, the increasing capabilities of today’s dental radiography technologies make the investment worthy of deliberate consideration. “The term dental radiography technologies would be more appropriately called dental diagnostic imaging because it involves more than a radiation-driven medium,” explains Claudio M. Levato, DDS. “Current types of diagnostic imaging are predominately radiographic, but magnetic resonance imaging (MRI), ultrasound and laser, and visible light transillumination also have dental diagnostic applications.”
Many dentists are turning to digital radiography systems as they update their practices to provide more efficient, streamlined services. A 2013 Millennium Research Group report analyzing current trends in radiography systems predicts this will continue. Additionally, a strong revenue expansion for dental imaging systems in the next decade is also expected, with contributing factors including increases in the demand for cosmetic dental procedures and the number of general dentists performing them.1
However, despite the promise of more vivid imagery, a streamlined workflow, and potentially more practice revenue, a huge number of practitioners today are reluctant to embrace the digital side of dentistry. Indeed, although digital radiography technology has been widely available since the late 1990s,2 utilization is not as high as one might expect.
“Unfortunately, in 2014 new dental radiography technology for many dentists still means transitioning from film to either solid-state sensors (ie, true electronic sensors) or possibly to photostimulable phosphor plates (ie, indirect digital imaging plates with phosphor coatings),” explains Dale A. Miles, BA, DDS, MS, adjunct professor at the University of Texas Health Science Center at San Antonio. “I say unfortunately because more than 50% of all dentists are still using conventional film-based technology. While they’ve gone digital in most of their consumer-based lives, many dentists still persist in using x-ray film techniques that are cumbersome, more costly, and less efficient.”
Why aren’t more general practitioners investing in digital radiography when the potential benefits include an optimized practice workflow, expanded or more detailed diagnostics, and more informed patients? The often cited—and certainly legitimate—barriers to switching to digital imaging systems include cost, training, and radiation exposure. The decision to invest is certainly one that every practitioner must make based on the needs and capabilities of his or her practice by weighing the technology’s benefits and drawbacks.
Benefits of Investment
Loyalty to film exists even though switching to a digital radiography system has been shown to improve practice efficiency.3 Digital imaging may also streamline diagnostic procedures and assist with patient education and co-diagnosis. In fact, these systems may prove to be the most useful investment a dental practice can make for a variety of reasons.
Better Patient Care
Today’s patients are more technologically savvy than ever before, and they expect digital technology as part of their care, according to Allen G. Farman, DSc (Odont). “Unlike in the past—when they may have felt they were paying a great deal of money for thumb-sized transparent negatives that they couldn’t really look at comfortably with their dentist and which cost them more than their passport photograph did—patients today can view radiographs on a large-screen television in high definition,” Dr. Farman observes.
Besides meeting patient expectations, one immediate benefit of integrating a digital system is the ability to use these images to educate patients thoroughly so they understand which aspects of their oral health need to be addressed. Dr. Farman explains that case acceptance can also benefit—the ability to forward radiographic images as PDFs to the patient’s mobile device means they can show them to a spouse to justify why treatment needs to be completed instead of taking the next big vacation or purchasing a new car.
Easier Learning Curve
Thankfully, the learning curve for adopting digital radiography today is not as long as the learning curve dentists experienced when mastering traditional film radiographs, Dr. Farman emphasizes. Even so, a common barrier to the adoption of digital radiography is that the clinician fears it will be difficult to learn.
“Dentists trained and educated using older technologies may have forgotten how long it actually took them to learn, and sometimes it’s difficult to teach an old dog new tricks,” Dr. Farman says. “But having taught radiology for more than 35 years, I have seen that the move from film to digital has resulted in a vast improvement in teaching dental radiography techniques.”
For example, traditional methods found students taking the radiograph using film, spending several minutes undertaking the development process, and then reviewing them. Now, if they’re using a solid-state digital radiography technology, they can view the image instantly and see exactly where they placed the detector, evaluate image quality, and retake the radiograph if necessary. Dr. Farman says digital dental radiography has made the learning process more efficient.
Although sticker shock remains perhaps the biggest barrier to adoption of digital radiography systems, the high volume of cases that will require this technology means a relatively quick return on investment (ROI)—something that is not always true with large technology-related capital investments.
“Understanding that the dentist still needs to examine the patient to determine what x-ray modality is required for diagnosis, and that the dentist should only prescribe or order those x-ray images necessary, fees from dental x-rays constitute the largest margin of any procedure that is performed in the dental office,” Dr. Miles elaborates. “If dentists use their practice management systems to query a ‘productivity report’ limited solely to x-rays taken in their office, they would see that they generate a substantial amount of money—in many cases more than enough to pay for any system in less than 1 to 2 years. Therefore, the return on investment is significant and rapid, and dentists should not worry about the overall cost. They will be providing patients with better diagnoses based on better images derived from using better technology with software tools that allow them to detect disease features more accurately and more often.”
Thorough and honest assessment of actual technology “needs” versus “wants” can clarify whether digital radiography will be a practical investment for the practice. Further, determining the procedures for which a digital system would prove most useful, such as placing implants or designing cosmetic restorations, can help dentists select the best system for the practice.
“We have radiographic machines and other technologies today that allow us to do virtual patient consultations, better assess TMJ cases, and support dentistry as an adjunct to treatments for such conditions as breathing disorders, so it becomes critically important for dentists to examine how they are going to use these technologies to maximize their benefits,” emphasizes Scott Benjamin, DDS, chairman of the ADA Working Group on Digital Imaging. “A common problem clinicians have is near-sightedness; they are looking at where they are and not where they want to be, and ensuring that the technology they are evaluating will meet those goals.”
Benjamin explains that arriving at a purchasing decision becomes an exercise in critically evaluating your practice. For example, how will the new system work with the current practice workflow? Will adjustments be required to staff schedules or duties? How much additional education and training will staff members need? This is often the most overlooked aspect in technology selection. What additional equipment and resources are also needed? Answering these questions can help dentists avoid purchasing overly difficult and possibly inappropriate systems that may disrupt the practice or cause unnecessary stress.
“Considering upgrade-ability and how radiography technology can remain and become valuable in the future will keep dentists moving in the right direction,” Dr. Benjamin elaborates. “For example, there are 2D panoramic imaging machines on the market that can be converted into a 3D small-field digital radiography machine in the future.”
Also key to making the right purchasing decision is evaluating the support offered by the manufacturer or dealer. Are training and support available pre- and post-purchase? What financing options are available? What technological infrastructure (ie, hardware, software) is necessary to support the new system? Will upgrades be necessary and, if so, how frequently?
“Advanced technology, especially 3D radiography systems, can improve productivity and bring greater satisfaction to the practice, but dentists need to do their homework,” advises Don Tyndall, DDS, PhD, professor of diagnostic science and director of oral & maxillofacial radiology at the University of North Carolina School of Dentistry. “They need to give as much attention to the company that manufactures the unit as they do to the specifications of the unit itself, and they need to ensure they’re adequately trained—along with their staff—to really get everything out of the investment.”
With Great Power
From a clinical standpoint, selecting the right digital radiography system also means knowing how much imaging power you need and understanding the limits and implications of the system you choose.
“2D radiography systems are less expensive and require less training, and manufacturers are making progress in developing higher resolution sensors and additional user-friendly software features,” explains Dr. Tyndall. “However, dentists—at the same time—should also understand that higher resolution doesn’t necessarily mean you can see more disease. The human eye can only see so much resolution, and beyond a certain point, higher resolution is not really that useful unless the dentist is doing a lot of magnification, such as in endodontically related tasks.”
Moving to a 3D system has many benefits, such as allowing clinicians to expand their diagnostic power or scope of practice, but properly understanding and interpreting the information displayed in these radiographs presents different issues, Dr. Farman warns. As digital dental radiography technologies acquire more complex volumes of data, interpreting that data takes on a new significance for the general practitioner and requires a longer learning curve.
“When dentists acquire a 3D image, they’re responsible for its content, which means they should avail themselves of training on how to view cone-beam CTs and recognize pathological conditions,” Dr. Tyndall advises. “Most state boards (or providences, if in Canada) hold the dentist who acquires the image responsible, whether that image is a bite wing, panoramic, periapical, or cone beam.”
Dr. Tyndall explains that dentists must go through and review the radiograph volume once they’ve acquired them. If they aren’t prepared to do that, then they shouldn’t buy a cone-beam system, he says.
Further, when dentists do encounter something on a radiograph that they don’t recognize, then the cone-beam CT can be referred to an oral and maxillofacial radiologist for an interpretation and report as part of the patient’s record, Dr. Tyndall adds. Although writing a radiology report in such a case is something that the oral and maxillofacial radiologist would handle, general practitioners must be able to differentiate what’s normal from abnormal.
Therefore, he advises dentists to ensure that training is offered with any cone-beam system that’s purchased. “By training, I don’t just mean how to use the unit to raise productivity, but in terms of how to recognize pathology,” Dr. Tyndall says. “Some companies provide free training, others offer courses for a modest fee, and others host web-based training, so there’s something for everyone. Dentists just need to consider training and the type that’s available as part of their purchase decision process.”
Addressing Radiation Concerns
A primary concern with any radiography system continues to be radiation exposure to staff members and patients. The ALARA (as low as reasonably achievable) principle states that healthcare providers who use ionizing radiation, including dentists, should utilize the lowest dose possible to get clinically acceptable results. Evidence from the National Council on Radiation Protection’s (NCRP) reports suggests that the dental profession has been adhering to this standard, but continuing education for all dental professionals is advised to minimize the risk of radiation exposure in their practices.7 The report provides examples to lower the risk of radiation, such as using the highest speed film systems possible for traditional analog systems or using an equivalent digital system, as well as to reduce the possibility of overexposure, such as by collimating the beam to a well-defined area.8
According to Jeffery B. Price, DDS, MS, associate professor and director of oral & maxillofacial radiology at the University of Maryland School of Dentistry, and adjunct associate professor of oral & maxillofacial radiology at the UNC School of Dentistry, there are three primary methods to maintain good radiation hygiene within dental practices today in relation to patient safety: justification of radiographic examinations, optimization, and limitation. Optimization in particular speaks to the ALARA principle, since it means performing the most appropriate radiographic examination with the smallest dose of radiation possible.
“An example of this would be ordering a panoramic radiograph with bite wings, when appropriate, for an adult patient with few or no restorations, instead of a full mouth series, since a panoramic and bite wings have a lower radiation dose for the patient,” Dr. Price explains. “Another example would be using the fastest receptors possible. If an office is still using D speed film and does not want to change to digital receptors, a change to F speed film is recommended in order to meet the recommendations of NCRP report #172.”
Limitation means collimating the x-ray beam to the area of interest, says Dr. Price. For intraoral radiography, this means using rectangular collimation, which can be achieved by changing the round cone of the position indicating device to a rectangular device; fitting a rectangular collimator over the end of the round opening of the position indicating device; or fitting a rectangular collimator onto the film positioning device. Rectangular collimation will reduce the patient’s radiation dose by approximately 50% to 60%, Dr. Price explains.
“There are always physical factors that determine how much radiation is required to optimize the image, such as patient size and age,” notes Dr. Levato. “Equipment modalities also effect the image quality, and certain image receptors require more radiation to produce the desired outcome.”
Also warranting serious consideration are the various standards and recommendations for digital radiography and imaging systems. Systems should be DICOM conformant, with images containing all information necessary to meet Digital Imaging and Communications in Medicine standards. DICOM images are not merely digital images, but contain pertinent patient data or notes about whether the images have been altered or enhanced.4 DICOM-standard systems ensure ease of information transfer among all dental professionals, giving clinicians the ability to seamlessly share and interpret patient data. This translates to more convenient and cost-effective visits among multiple practices.
To facilitate such interoperability, the American Dental Association Standards Committee on Dental Informatics maintains the IHE (Integrating the Healthcare Enterprise) Dental Domain working group. IHE works with healthcare groups to ensure thorough implementation of DICOM standards throughout the profession. Members also work directly with vendors to test their efforts and resolve technical issues that arise.5
With this ease of information sharing comes the need to ensure that patient privacy regulations dictated by the Health Insurance Portability and Accountability Act (HIPAA) are met. Under HIPAA, healthcare providers who electronically transmit any patient-related health information in connection with regulated transactions are known as “covered entities.” Electronic billing is often the thing that qualifies healthcare providers, including dentists, as covered entities.
The Security Rule is the section of HIPAA that pertains specifically to covered entities who use and store electronic forms of protected health information, including digital radiography images. It requires that such information be maintained with confidentiality, integrity, and accessibility, and that practices conduct a security risk assessment to demonstrate their ability to protect patient health information.
To help covered entities assess their compliance with the Security Rule, the National Institute of Standards and Technology has developed a free desktop-based toolkit application that is available for download from their website (https://scap.nist.gov/hipaa). For practices that use mobile devices, a collaborative effort by the HHS Office of the National Coordinator for Health Information Technology (ONC) and Office for Civil Rights (OCR) recently yielded a free Security Risk Assessment (SRA) tool for Windows- and iOS-based mobile tablet devices. More information about the SRA is available at www.healthit.gov/providers-professionals/security-risk-assessment-tool.
Is the transition from film to digital radiography inevitable for every practice? Probably not. As more options become available, however, the benefits for practice efficiency and patient care should continue and even increase. Clinicians who wish to take advantage of going digital will want to use careful consideration and in-depth planning, along with staff and vendor consultation, to streamline the acquisition process and allay any fears or hesitations.
“3D radiographic imaging is the hottest application today, but we have seen improvements on all fronts. The newest sensors have improved resolution over their predecessors, and the cost of 3D imaging has become more affordable with the smaller FOV combination CBCT/PAN units,” notes Dr. Levato. “What I believe will impact dentistry the most is the interoperability and collaborative nature of 3D applications.”
“Dentists will add patient photographs, optical impressions, functional movements of the jaw, and occlusion, combining all of this information in the computer for a virtual patient record for diagnosis, treatment planning, and designing and fabricating restorations and appliances,” Dr. Tyndall elaborates. “It’s pretty clear dentistry is heading in this direction, and cone-beam CT is going to be a pretty big part of it. We’ll still need 2D imaging as well, and I don’t see that phasing out any time soon.”
There is a great deal of integration taking place in dentistry with the move toward digital dentistry, and cone-beam CT will be a foundation for that, Dr. Tyndall observes.
1. Global market for dental imaging systems will reach over $2.3 billion by 2022. Millennium Research Group. www.mrg.net/News-and-Events/Press-Releases/Dental-Imaging-System-Markets-091813.aspx. Accessed August 20, 2014.
2. Farman AG. The 2013 tech issue: diagnostic imaging. Inside Dentistry. 2013;9(7):46-47.
3. Hoos JC. Practice efficiency using digital radiography. Pract Proced Aesthet Dent. 2006;18(1):46.
4. Farman A. DICOM for digital imaging and communication in dentistry. Inside Dentistry. 2009;5(8):80-83. www.dentalaegis.com/id/2009/09/dicom-for-digital-imaging-and-communication-in-dentistry. Accessed August 20, 2014.
5. Williams J. Group developing process to exchange digital dental images securely, privately. www.ada.org/en/publications/ada-news/2012-archive/may/group-developing-process-to-exchange-digital-dental-images-securely-privately. Accessed August 20, 2014.
6. To whom does the Privacy Rule apply and whom will it affect? National Institutes of Health website. https://privacyruleandresearch.nih.gov/pr_06.asp. Accessed August 27, 2014.
7. Preece J. NCRP 145 Radiation Protection in Dentistry: A Challenge for the Dental Profession. www.aadmrt.com/article-4---2011.html. Accessed August 20, 2014.
8. NCRP Report No. 145, Radiation Protection in Dentistry. https://www.ncrponline.org/Publications/Press_Releases/145press.html.