Interview: “You cannot push people into digital dentistry”
It is safe to say that Prof. Markus Blatz has dedicated his life to the furthering of clinical and theoretical knowledge in order to advance dentistry. His passion for the dental profession is unmistakable and can be seen in his numerous degrees, professional awards and academic publications, among other achievements. In his current role, Blatz serves as chair of the Department of Preventive and Restorative Sciences and assistant dean for digital innovation and professional development at the University of Pennsylvania School of Dental Medicine in Philadelphia, U.S., where he founded the Penn Dental Medicine CAD/CAM Ceramic Center and is leading the Digital Innovation Initiative. In this interview, he discusses all things digital dentistry, including the CAD/CAM workflow, 3D printing and the use of artificial intelligence (AI).
Prof. Blatz, you’ve dedicated a large part of your life to dentistry and have received numerous teaching and research awards. What inspired you to start using digital technology in your clinics, and how happy are you with the results?
Innovative clinical protocols, new technologies and advanced treatment concepts that have a positive impact on patient care have always been at the center of my work, going back to my time at the University of Freiburg in Germany. A strong quest for clinical excellence and an excitement about new technological developments and materials, paired with a deep passion for teaching and research, motivated me to engage in digital dentistry and material research early on. However, I am not someone who always has to have the “latest and greatest” tools out there. For me, these tools need to provide a true benefit for our patients and have at least some scientific support.
Current digital workflows, including intra- and extraoral scanners and chairside and laboratory-based CAD/CAM systems, have reached a level of quality as good as or even better than conventional ones. Quality, accuracy and precision of fit achieved with digital tools are excellent and undergo constant improvements. Another key argument is the enhanced patient experience, for example, through intraoral scanning, digital smile design or in-office restoration fabrication. Just ask patients which impression technique they prefer: digital or conventional rubber impressions. Also, using a scanner allows the rescanning of irregularities without having to remake the entire impression.
You are leading the Digital Innovation Initiative at the University of Pennsylvania’s School of Dental Medicine. Could you tell us a bit about the initiative and your role in it?
As chair of the Department of Preventive and Restorative Sciences, I am responsible for the entire preclinical, clinical and postgraduate education in operative dentistry and prosthodontics. We are teaching a comprehensive care model that embraces all aspects of modern restorative dentistry, from caries control to complete dentures and implant-supported reconstructions. In my role as assistant dean for digital innovation, I developed and implemented a school-wide strategic plan for integrating new technologies in clinics, preclinical education, dental laboratory technology and research.
I believe that having experts in some central leadership positions is key to success. Soon after I had joined Penn Dental Medicine (PDM) in 2006, we hired a master dental technician from Germany who had extensive experience in CAD/CAM technologies. Together, we founded the Penn Dental Medicine CAD/CAM Ceramic Center, which is a unique industry-supported venture that focuses on digital planning, workflows and materials in dental laboratory technology. The appointment of a clinical CAD/CAM director to lead the training of students, residents and faculty with chairside CAD/CAM technologies has ensued more recently.
In late 2019, we opened the Digital Design and Milling Center, a state-of-the-art facility featuring chairside digital technologies including scanners, design computers, milling machines and ceramic furnaces. In this center, there is a designated dental technician who assists dental students with the design and fabrication of restorations.
Novel learning technologies and pedagogies that recognize students’ learning styles and preferences are also part of the digital innovation initiative. The PDM learning technology team, which I founded and supervise, includes curriculum designers and learning technology experts. The team is responsible for the development of blended e-learning/online curricula and continuing education courses, digital course manuals (iBooks), videos and modules for blended learning, examination software, MOOCs (massive open online courses) and “gamification” tools and for the integration of AI, virtual reality and haptic technologies. Virtual reality dental training simulators have been part of our educational programs for many years.
You’ve been actively involved in the initiative since Day One and have contributed greatly to its success. What are you most proud of, and did it live up to your expectations?
Definitely, I am most proud of our great team, staff, faculty and students. Despite initial hesitations about digitalizing our workflows, undergoing intense training helped us realize that these tools make our work easier and more predictable. You cannot push people into digital dentistry, but you can show them why and how to use it and what the real benefits are.
It appears that the COVID-19 pandemic has given digital dentistry, especially chairside restoration fabrication, a great boost. In order to limit the number of times one has to change protective gear and clean the treatment area, dental professionals now carry out more procedures in one longer appointment. This means that it is now possible to fabricate indirect restorations in one such appointment. Additionally, the reduction of laboratory expenses is significant. However, the clinician can still choose to send the intraoral scan files to an outside laboratory, so all previous options are still available.
“The COVID-19 pandemic has given digital dentistry, especially chairside restoration fabrication, a great boost”
The use of our Digital Design and Milling Center has been tremendous and exceeded even my wildest expectations. In fact, we are now fabricating between 70% and 80% of single-unit restorations from our student clinics with chairside CAD/CAM technology!
What are some of the state-of-the-art tools, techniques or software that you’re using in the School of Dental Medicine, and how do they facilitate your work and that of your students?
The laboratory-based CAD/CAM Ceramic Center features multiple face and model scanners, three industrial five-axis milling machines that can mill a full spectrum of materials and types of restorations, and multiple sinter furnaces. There are several computer stations with professional 3D designing software that can design and fabricate pretty much any type of restoration, from single-units to tooth- and implant-supported full-mouth reconstructions. The centerpiece is newly developed virtual treatment planning software that produces digital wax-ups in a timely and predictable manner.
The Digital Design and Milling Center for in-office CAD/CAM technologies features 12 design computers and various software programs for planning, designing and milling restorations. There are ten high-speed milling machines and eight ceramic furnaces for firing and finishing restorations. Students learn to select, mill and finish the materials for their patients’ restorations. Currently, we have 17 intraoral optical scanners throughout the school’s clinics, and we are expecting to receive more equipment soon, some of it updated.
Our goal is to scan every patient who comes to our clinics and to eliminate preliminary alginate impressions for the diagnostic cast. To that end, both centers are equipped with new 3D printers. We also incorporate digital files into electronic health records. This has various advantages, including the space-saving storage of diagnostic models and the fabrication of an identical restoration in the event of failure.
As a university that distinctly focuses on the sciences, all of the above facilities, tools, workflows and materials are being heavily used for research. Our studies cover the entire spectrum of modern restorative dentistry and CAD/CAM technology, with a special focus on the physical, optical and biological properties as well as the manufacturing of new materials. Students and residents engage greatly in our research activities, as evidence-based dentistry plays an integral role in our education, training, treatment planning and clinical care.
When entering our programs, every student receives an iPad already equipped with the necessary documents, applications, software and files. One of these applications is dedicated to digital smile design in order to allow students to learn about dental and facial esthetic parameters and, ultimately, include these in the treatment planning process, so that they are able to share planned smile designs and prospective outcomes with the patient even before the treatment commences.
You would probably agree that it is crucial to educate dental students on the latest advancements in dentistry. What possibilities does digital dentistry open up for training dental students, and how ready and willing are your students to embrace digital technology?
Although many private practices may not have yet embraced digital dentistry, it is the way of the future. The predoctoral and postdoctoral curricula have been adjusted to require students to gain in-depth experience with CAD/CAM technologies. Digital tools are second nature to them, and they adapt to a virtual and digital environment with ease. Even first- and second-year students are already learning how to use intraoral scanners and digital design in the preclinical simulation laboratories. Not only are they willing to engage but also, they are excited about these technologies and embrace them with enthusiasm.
You specialize in materials science, prosthodontics and esthetic dentistry. How did the application of CAD/CAM-milled materials and 3D-printed materials redefine your own workflow?
I believe that 3D printing is the future of restoration fabrication in dental laboratory technology. One of our goals is to print a crown in various layers with different ceramics, translucencies and colors in order to truly replicate a natural tooth. At this time, however, subtractive manufacturing, such as milling, is the predominant fabrication technology in the digital CAD/CAM workflow. Despite current limitations, especially related to the accuracy, print quality and material options, 3D printing certainly has its place in the digital workflow, namely for the fabrication of occlusal splints, surgical guides, denture bases, provisional restorations and study models. In the future, 3D printing will likely be used for all types of materials and restorations, but we still have a way to go.
Would you like to add anything else?
Besides digital impression making and restoration fabrication, CAD/CAM technologies are increasingly used in the diagnostic and treatment planning stages. This includes technologies that detect caries, automatically read radiographs and collect patient information from CBCT, intra- and extraoral scans and photographs in order to develop an individual treatment plan.
“AI will soon become critical in esthetic and functional planning and design and material selection, customized for each patient”
Also, AI is becoming more prevalent in automating many of these steps while removing subjective operator-related bias. AI will soon become critical in esthetic and functional planning and design and material selection, customized for each patient. We will also use information technology to track and compare general and oral health data to better understand the pathology and prevalence of certain diseases. Merging these data sets and applying AI will enable us to understand disease like never before. It will also help us improve preventive measures and be more targeted in our efforts to better treat our patients.