Although MRI machines are not new, their introduction to the dental industry can lead to big changes in patient care.
The University of Minnesota School of Dentistry in Minneapolis recently welcomed the first dental-dedicated MRI in the U.S. The technology was unveiled with the opening of the school's Orofacial MRI Center, which is led by Donald Nixdorf, DDS, and Laurence Gaalaas, DDS.
Dr. Gaalaas recently spoke with Becker's about the potential of MRI in dentistry.
Editor's note: Responses were lightly edited for length and clarity.
Question: When did conversations start about bringing the first dental MRI to the university?
Dr. Laurence Gaalaas: Several years ago, my colleague, Dr. Don Nixdorf, started conversations with industry partners Dentsply Sirona and Siemens Healthineers to bring a dental MRI system to the University of Minnesota School of Dentistry. As far back as about 2010, however, there has been hard tissue MRI research and work performed at the University of Minnesota including MRI imaging of teeth. So while the MRI unit feels new to us here, we've been working on the topic for quite a while.
Q: Can you tell me a bit more about the potential of this technology now that you have it at the school?
LG: The big development, which was really born out of the University of Minnesota's prior research, is being able to image hard tissues like bone and teeth with MRI. The technology has a really long and established track record as being great at imaging soft tissues. Also, MRI design and safety mechanisms have become less expensive, and so all of that means the technology has become more feasible for dentistry. What we can see now on images, in addition to the hard tissues that we're accustomed to in dentistry, are all the soft tissues. Furthermore, we expect we can see inflammatory changes better and more directly on MRI than we can with X-ray based technologies. A specific example we'll be evaluating and studying is endodontic disease. When previously we saw a lesion in the bone on a radiograph, we now expect to get more information about exactly what type of lesion it is. And then following endodontic treatment, document whether that particular lesion heals properly or not.
An additional area of research we will be performing is on the growth and development of growing patients in orthodontics. Traditionally, orthodontics has used X-ray based imaging to study and evaluate young, growing patients. This focus applies to craniofacial and other head and neck conditions, as well such as cleft lip and palate as well. Overall, we haven’t been able to meaningfully study those patient groups because of the hazards associated with the use of X-ray based ionizing radiation. Now, with non-ionizing imaging technology, we can start to revive those growth and development studies and not just look at the hard tissues, but the soft tissues as well, which is, again, fairly new for recent dental research and clinical care.
The third main area of research we’ll be performing is temporomandibular joint imaging. MRI imaging, for decades, has been the gold standard for TMJ imaging to look at the disc and soft tissue components, so the topic really is not new. But with the technological advancements of our unit, we are able to improve the hard tissue imaging of the TMJ and aspects of the soft tissue imaging simultaneously. We have many other studies on our "to do" list in the long term, but those three areas are where we are going to start now.
Q: How do you see MRI becoming more widely used in the dental industry going forward?
LG: I think MRI will become an established and widespread dental research tool, as it has right now at the University of Minnesota. Whether the technology really takes hold in clinical dentistry, in the same way cone beam CT has, depends on a couple of things. The correct research has to be performed and establish that there are day-to-day clinical dentistry applications where this latest version of MRI is beneficial. While there are obvious benefits to avoiding ionizing radiation with MRI, dentistry has such a long and successful track record with X-ray based imaging at relatively very low doses to patients, that we're being diligent about performing the work to confirm, yes, MRI is a truly useful technology to support clinical dentistry.
The other technological advancement, in order for MRI to really take hold in clinical dentistry, is to develop MRI units that are even smaller and more easily installed. Our current unit, even though it's one of the newest, smallest and relatively least expensive MRI units available, is still a little too big for a conventional dental practice office space. Finally, there are some additional safety considerations associated with the magnetic field and the radio frequency energy employed by MRI, plus dental clinicians using the new technology would need additional professional training.
Dr. Nixdorf and I have recognized these needs and as far back as 2018 published a textbook chapter about what it was going to take to get dental MRI in dental clinics. We are now pursuing initiatives to hopefully develop smaller, even less expensive magnets, and also bring forward continuing education programs to get dental researchers and clinicians used to and comfortable with this new modality.
Q: What are you most excited about when it comes to leading the orofacial center?
LG: MRI in dentistry is new and exciting, and the patient images are so fun to look at because image quality has improved so much in recent years. I remind myself and all of my students though, that just because an image is high quality doesn't automatically make it diagnostically useful to the patient. What is most motivating for me is now that we have a system which uses many of the latest technological advancements and produces high quality images, we can put it to work and see what real clinical questions it can answer for dentistry. In other words, what treatment decisions it can help dental professionals make to support improved patient outcomes. Everything we're doing comes down to just that: helping clinicians get better answers and make better decisions, which leads to better treatment outcomes.
Q: Are there any other technologies that are really interesting to you right now?
LG: The other technology I believe will significantly influence dentistry, and already has, is artificial intelligence. We're already seeing AI being developed and deployed in diagnostic image reconstruction. This application is not necessarily an artificial intelligence-derived diagnosis, but rather the production of higher quality images with more diagnostic information with less raw data input. For example, with AI, we can acquire higher quality images with a shorter overall MRI scan time or lower CBCT radiation dose. Some other efforts have demonstrated that AI can indeed assist clinicians in making high quality diagnostic imaging decisions. AI is not limited to diagnostic imaging, however, and I think AI will be applicable to many aspects of clinical dentistry and education. The future will certainly be exciting.