“Every Tooth Matters”: Dr. Shreyas Oza on 3D Printing, AI, and Patient-Centered Endodontics (Part-2)

Dr. Shreyas Oza: One of the most significant advancements in recent years—by recent, I mean the last 10 to 20 years—is the advent of CBCT (Cone Beam Computed Tomography). The difference between a regular digital X-ray and a CBCT scan is that a normal X-ray superimposes the entire thickness of the jaw onto a two-dimensional image, causing a loss of detail. CBCT, on the other hand, allows you to see every slice of the jaw in detail, from different angles—side, top-down, and front-to-back.

A study showed that when endodontists diagnosed a case using only traditional X-rays and were then provided with CBCT scans of the same patient, their treatment plans changed over 60% of the time. That is a huge difference! That’s why, in my practice, every patient receives a CBCT scan, regardless of which tooth I am treating.

Other recent advancements include modern irrigation systems like GentleWave and laser-assisted irrigation. There are also newer materials, such as bioceramic sealers and flexible file systems made with advanced titanium metallurgy, making it easier to navigate curved and tight canals. These innovations have significantly improved day-to-day clinical practice, and I incorporate most of them in my work.

There are also ongoing developments in areas like 3D printing, which was the subject of my thesis on its applications in endodontic microsurgery. While it has clinical applications, most practitioners don’t have the bandwidth to integrate it into daily practice yet. Another growing field is guided endodontics, which can be dynamic or static. Nanotechnology is also making its way into endodontics, improving sealers with nanoparticles for better sealing, bioactivity, and antibacterial properties.

Artificial intelligence is another emerging trend. While AI in endodontics is still in its early stages, it is already being used to analyze X-rays and CBCT scans. Although it hasn’t yet been integrated into the actual treatment process, it is gradually progressing.

Dr. Shreyas Oza: I’m really glad you asked this question. The American Academy of Periodontology (AAP) recently published a statement emphasizing that when a tooth can be saved, it should be saved. There’s no need to unnecessarily extract teeth and replace them with implants unless absolutely necessary.

Keeping your natural tooth helps maintain bone height and proprioception—the ability to sense the position and pressure on the tooth—because of the periodontal ligament surrounding the root. When you replace a tooth with an implant, you lose that sensory feedback, which can sometimes cause more damage in the long run.

Additionally, implants require meticulous maintenance and are not immune to failure. If an implant fails, you may need more bone grafting and a new implant, which has an even higher chance of failure. Therefore, whenever there is an option to save a tooth, it is always the best choice. If saving the tooth is not feasible, then alternative options can be considered.

Dr. Shreyas Oza: 3D printing in endodontics is a vast topic, and I really enjoy discussing it.

When I started to do my preliminary research about 3D printing in Endodontics, I found that many researchers are using 3D-printed models to study how endodontic files function inside teeth and how efficient they are in cutting dentin. These models are also used in academia to train dentists on performing root canals.

For my thesis, I took a CBCT (Cone-Beam Computed Tomography) scan of a patient who required microsurgery, converted the 3D scan into a 3D-printed model, and allowed my co-resident to practice on it before the actual surgery. The endodontic resident reported feeling much more confident going into the procedure after practicing on the model. We went on the undertake a formal study of the effect of 3D printed patient models on treatment planning and operator confidence. This demonstrates the academic benefits of 3D printing.

Clinically, 3D printing has several specific applications, for example, as static guides. When a canal is particularly small, a 3D-printed static guide can be used, similar to how guides are used in implant placement. The process relies on CBCT scans and intraoral scans to create a guide that sits on the teeth. The guide provides a precise path for the instrument, ensuring accuracy and simplifying the procedure.

Additionally, 3D printing is beneficial in endodontic microsurgery. In microsurgical procedures, rather than accessing the root from the top, we approach it from the side. A 3D-printed guide helps pinpoint the exact location of the root end, making the surgery more precise and efficient.

Of course, there are limitations. For example, using 3D-printed guides for standard root canals is impractical in posterior teeth due to limited vertical space. This technique is primarily used for anterior teeth and sometimes premolars.

Currently, there is no 3D-printed solution for obturation, but advancements are continually being made. Another interesting application is in autotransplantation. If a patient needs a tooth transplant, a CBCT scan of the wisdom tooth can be used to 3D print a model. During surgery, the bone can be prepared based on the model, ensuring a perfect fit before extracting and transplanting the tooth. These applications highlight the potential of 3D printing in endodontics, and I'm sure we’ll see even more innovative uses in the future.

Dr. Shreyas Oza: Precision depends on the specific application. Some procedures require higher accuracy than others. For example, when 3D-printing a wisdom tooth model, micron-level precision is not essential. However, if you are 3D printing a crown, it must fit perfectly to prevent microleakage.

For 3D-printed guides that sit on teeth, accuracy is ensured by using highly precise intraoral scans. The scan ensures the guide fits accurately on the tooth, and from there, only the thickness of the burr matters. In endodontics, extreme precision is not as critical as in other areas like prosthodontics, where even minor discrepancies can cause bacterial leakage.

The accuracy of 3D printing also depends on the printer and the material used. Resin-based prints, for example, can shrink over time, so the timing of usage after printing matters. Additionally, the accuracy of CBCT-based 3D printing relies on the quality of the initial scan and how the data is processed. If there are errors in data acquisition, the final printed model may not match the actual tooth size. Operator expertise plays a crucial role in minimizing these inaccuracies.

Dr. Shreyas Oza: Yes, although many challenges can be overcome with increased investment. One major issue is material selection. Not all 3D-printable resins are safe for intraoral use. Cheaper resins may contain harmful substances like polymethyl methacrylate (PMMA), which can leach into tissues. High-quality, biocompatible resins are available, but they are more expensive and, depending on the application, require more expensive 3D printers.

In general dentistry, 3D printing has become widely accessible. Most dental labs now use 3D printing for crowns rather than traditional methods. However, in endodontics, 3D printing is still evolving. Researchers are exploring new materials, including 3D-printed bone and tissue, but these advancements take time to reach clinical practice.

Dr. Shreyas Oza: The future of dentistry is evolving rapidly, both in India and globally. Every specialty is experiencing advancements, from prosthodontics to endodontics, with new materials and techniques emerging regularly.

Artificial intelligence (AI) is a game-changer. AI is being integrated with intraoral scanning and digital workflows to enhance diagnosis and treatment planning. There are even discussions about developing AI-driven systems that could, theoretically, reduce or eliminate the need for human dentists—though I believe we are still far from that reality.

Overall, the future of dentistry is incredibly exciting. Advances in material science, AI, imaging technology, and surgical techniques will continue to transform the field over the next decade.

Dr. Shreyas Oza: My patients! I have the nicest patients. Although there are wealthy parts, Arlington is not a very wealthy suburb; it's an average, hardworking, common American community. The patients are very kind, and for the most part, they just want to get out of pain. If I have a patient in the chair who hasn’t slept for two nights, and I get them numbed up—even before I start the access, the patient is already dozing off, snoring—there's nothing more rewarding than that! Because I know that once they leave my chair, they'll be pain-free. So, yes, the patients and their response to treatment is definitely the best part of endodontics. Having the ability to relieve their pain is incredibly exciting for me.

Dr. Shreyas Oza: In the U.S., as a specialist, you never get easy cases—every case is difficult! But two cases come to mind.

The first was a 32-year-old patient—a really nice guy, always cheerful—but you could tell he wasn’t in good health. He needed a root canal on a premolar and was in severe pain. On top of that, he had extreme dental phobia. When I say severe, I mean he did not want to be there, but he was still trying his best to stay calm and even joked around. He hadn’t slept for 2-3 nights.

Let me give you an idea of his medical condition—he was only 32, yet he had already undergone two hip replacements, a knee replacement, had osteoporosis, and ankylosing spondylitis. He was used to chronic pain, but this dental pain was unbearable for him. I explained the treatment in detail and gave him the opportunity to ask questions. He told me, “I’m extremely anxious, and I need something to calm me down.” So, I suggested nitrous oxide sedation.

The tooth had an almost 90° bend, which made the procedure extremely difficult. But it turned out well, and he was so happy with the treatment that not only did he come back for two more root canals, but he also refers his entire family and all his friends to when they need endodontic treatment. That’s the biggest compliment I could receive.

The second case was referred to me by my wife, who is also a general dentist. The patient had been on IV bisphosphonates for several years—about 4-5 years—which is long enough to cause bone changes that make extractions high risk for developing medication related osteonecrosis of the jaw. She needed a root canal on her upper right first molar (tooth 16), but the pulp chamber was completely demineralized. There was no visible root canal system—just a solid chunk of tooth. However, she had periapical radiolucency.

I explained to her that even if I attempted the procedure, there was a high chance I might end up doing more harm than good. Since there would be a high chance of perforation in attempting to looj for canals I suggested an extraction instead. She went back to my wife, who told her, “No, you cannot extract this tooth. You’ve been on bisphosphonates. Go back to him—I know he will be able to do it.” So, the patient returned and said, “Your wife told me you have to do it, and you will do it.” Now, it’s my wife—I can’t say no! (laughs)

I went ahead with the procedure, and despite the challenges—at times, I was sweating bullets because I couldn’t see anything—I was able to locate all the canals, including MB2, which, as dentists know, can be notoriously difficult to find even in teeth with "normal" anatomy. I thoroughly cleaned everything, completed the root canal, and now, three years later, the patient is still doing great.

I document my challenging cases on Instagram (https://www.instagram.com/ozaendo). But yes, challenging cases are often the most rewarding. I always try to be honest with my patients about the difficulties, potential complications, and possible outcomes—both positive and negative. There’s a saying: “If you inform them before it happens, it’s a reason; if you inform them after, it’s an excuse.” That’s an important principle to remember.

Dr. Shreyas Oza: I would love to incorporate advanced techniques—everything can always be improved. For example, GentleWave technology and lasers have been shown to irrigate teeth very effectively.

That said, I’m very happy with my current approach because what we practice today is considered modern endodontics, with success rates of over 90%—sometimes even 94%, depending on the study. Further advancements might not drastically improve success rates because you can only go from 94% to 97%—you’ll never reach 100%. There will always be failures.

For me, anything that makes endodontics easier is worth incorporating. One example is a software called EVOLDX, which enhances the visualization of 3D CBCT scans. It’s already available, but it's a bit expensive, so I’m waiting to integrate it. If I could use a tool like that to better see the anatomy, I would know exactly where to go, which would significantly improve my execution.

Overall, I’m excited about where endodontic technology is headed. Do I want lasers? Yes. Do I want GentleWave? Yes. Do I want EVOLDX? Yes. But the most exciting advancement for me would be improved imaging technology like EVOLDX and AI integration.