Virtual Reality in Dentistry: A Match Made in Heaven?

Modern dentistry is a pretty painless practise, but all the cutting-edge dental techniques in the world do little for the anxiety of individual patients. In the collective imagination of the public going to the dentist is something to be feared. It’s no help that serious anxiety is an increasingly common occurrence in modern life.

The Psychology of Pain

It’s easy to think of pain as an objective, mechanical phenomenon. A signal that travels from the injury location as a nerve impulse to the brain. However, pain is a complex subject of which the measurable aspects are simply a tiny part. In fact, the subjective experience of pain may have little to do with the nociception, the neural process of pain.

Not all people experience pain in the same way. Some people have more tolerance for it than others. It’s also possible for people put into certain states of mind that reduce or eliminate the perception of pain.Hypno-analgesia has some good experimental evidence for pain control. There are also many historical and extant examples of ritualistic behavior related to religion or spirituality that inflict physical injury without significant perception of pain.

It has also become apparent that pain perception relies on contextual cues as well. The body transfer illusion tricks subjects into thinking a rubber hand is their own. Stick a needle in the rubber hand and the person experiences pain in the absence of nociception. Idiopathic pain can often be traced to psychological disorders related to depression or anxiety. Fear and anxiety can also worsen the intensity of pain.

Clearly, given that the experience of pain is such a complex subject, ensuring the comfort of dental patients takes more than pain-blocking chemicals and techniques that minimize physical trauma.

VR As Psychological Aid in Dentistry

This is where the main purported use case for Virtual Reality in dentistry comes into play. The idea is to remove visual and auditory stimuli from the patients perception associated with the procedure, pain or fear. There’s also the effect of pure distraction to consider. The replacement stimuli are pleasant and interactive. It could be something as simple as laying on the beach or a guided mindful meditation session. The jury is still out on what the best content might be, but the only limitation lies with the imagination of the content authors.

Why Now For VR Dentistry?

Virtual reality has been around since the early 90s, so why is there so much interest in the dental industry only now? There are more than a few reasons, but we can narrow it down to cost, size and fidelity.

Until around 2016, the cost of virtual reality hardware was prohibitive. Certainly there was no way to move VR products in a consumer space. Which is why you’d only find VR systems in research institutions, major arcades and some high-level training scenarios.

When next-generation VR products became available around 2016, they were much cheaper thanks to advancements made in smartphone technology. Smartphones enabled the development and mass production of sophisticated miniature displays, motion sensors, processors and so forth. These advancements are all found within modern VR headsets.

The second major reason VR is now so relevant to dentistry is the incredible reduction in size of the headsets and other related equipment. Before this new generation of VR, there would certainly be no space to fit such a system into the same room dentists perform procedures. Now we have entirely self-contained VR headsets no larger than a diving mask and tethered headsets that will work wirelessly. This makes it practical to integrate them into the procedure room.

The final reason VR is now compelling is the leap in fidelity. Early VR systems had primitive graphics and poor motion tracking. Which meant they were more likely to give someone a headache or make them feel seasick than provide any sort of relief. Modern VR is good enough to provide a convincing sense of “presence”. Which makes all the difference in terms of distracting patients from the potential unpleasantness of their procedure.

VR Dentistry in the Field

Research on the efficacy of VR in dentistry is ongoing, but there have been several studies that show it’s more than just a hypothesis. The first meta-analysis by Nansi Lopex-Valverde and her colleagues of VR as a way to relieve pain and anxiety found that it does indeed seem like an effective method. 

Another study, which aggregated data from multiple centers in a randomized crossover trial, indicted that cheap VR solutions such as the Google Cardboard, could be a “safe, portable, and cost-effective way to alter the perception and improve tolerance of pain.”

There’s also anecdotal evidence aplenty, such as Dr. Mark Whitlock’s use of VR to calm patient’s anxiety. Practitioners like him have gone ahead and included VR into their practice, presumably because the potential harm is negligible as long as approved pain control methods are not compromised.

VR Dentistry Training

While the focus right now seems to be largely on what VR can do for patients in the chair. However, VR holds amazing potential for training in all medical fields, which of course includes dentistry. While there is still no replacement for hands-on training or the use of physical procedure simulation, VR can let students put in more practice time than is possible with otherwise limited resources.

Modern VR systems can be used with advanced haptic systems and custom instrumentation to simulate the real feeling of doing various procedures with your hands. Be prepared for VR technology to play a much larger role in the training and education of a new generation of practitioners.

This video presentation of the “Intelligent Virtual Training Environment for Dental Surgery” is the perfect showcase of the concept.

In the video you can see students using an off-the-shelf HTC Vive headset as well as a haptic pen device similar to the 3D Systems Touch. With this equipment and, of course, sophisticated simulation software it’s possible to offer hundreds of hours of practice to students. It also opens up new assessment possibilities both by automated systems and lecturers.

The Potential of Tele- and Robotic- dentistry Through VR

The fall in cost of VR equipment and the existence of precise haptic systems to translate our real world movements into digital form and back creates the opportunity for teledentistry. We’ve already seen sophisticated surgical robots such as the Da Vinci system used by surgeons to operate on patients that are hundreds of miles away.

Basic teledentistry as it has been applied to date usually involves a video call or simply a consultation over the phone. To assess minor complaints that can be solved or temporarily alleviated through medication  or dental emergencies where patients cannot immediately get in-person help and need professional advice.

In 2017 history was made in China when a dental robot operated on a human patient for the first time. It’s conceivable that future dental operations could be, in some cases, performed with a combination of robotics and VR.

Potential Downsides to VR in Dentistry

The excitement around VR and its potential to make the dentistry experience for patients much more pleasant is understandable. However, there are some serious caveats that have to be taken into consideration.

First and foremost, VR equipment must fit into the same sterility standards as dental practices are already required to maintain. Since VR headsets are worn directly on the patient’s head and is in close proximity to the operation site, it’s likely that biological materials will attach on the surfaces of the device.

Some VR headsets have porous components, such as spongy cushions for the facepad. Standard VR headsets may not stand up well to common sterilization substances. Medical-grade VR devices may need to be employed or modifications may have to be made on existing commercial products. Since this is still a new technology in a dentistry context, the scope of the issue remains to be seen.

The next downside is that communication with the patient may be more difficult if they are distracted. Removing and replacing the VR headset is impractical, unless it’s a halo-band style headset that can be flipped up or down as needed. Interrupting the patient’s VR session may also reduce or remove any anxiety or pain reducing effect. Unfortunately, it’s often necessary to 

Issues of Consent and Approved Medical Practices

The use of VR to reduce anxiety and pain is a topic of current research. While several quality papers have been published showing significant degrees of efficacy, there is still much we don’t know about this approach to patient comfort.

For example, is it suitable for all types of procedure? What are the best practices when putting VR into the mix? Can a reduction in chemical pain blockers be justified when using VR? It will take some time before the use of VR will have the full backing of medical boards. While the risks of using VR in addition to approved pain control measures are most likely minimal and, on balance, in favor of patient comfort, reducing other pain control methods raises ethical issues.

Acceptance Virtually Assured?

We’re probably a long time away from any sort of formal regulation, requirements or push from authorities to use VR in dentistry. However, the early signs look good for VR to be another powerful tool in the arsenal dental professionals have to improve patient comfort and outcomes. If you’re a dentist or someone who works in the industry, you should at the very least be familiar with the overall direction and capabilities of VR. It’s a technology that will change more than just a single field!