Inside Dental Assisting
Volume 11, Issue 2
Published by AEGIS Communications
Digital Impressions: Dentistry in Evolution
Should your practice go digital?
Since starting in the dental lab industry more than 15 years ago, this author has seen countless changes and improvements in production and workflow, mostly due to the technology that has been created or transformed and how it continues to change the way dentistry is performed. From the software that organizes and tracks the daily schedule of patients to the improvements in diagnostics and imaging, the entire clinical experience for the patients is better and the clinical workflow is much improved. In this article, the author will discuss digital impression technology and the digital workflow between the dental lab and dental clinic.
The concept and practice of digitally scanning a patient’s mouth and fabricating restorations from that digital information is not new and dentists have been digitally capturing impressions for the past 30 years, yet today most dental teams continue to use traditional vinyl polysiloxane (VPS) impressions. The author is witness to several key reasons for why some dentists remain reticent to change to digital. One factor until now has been the cost of the digital scanners themselves, which is now decreasing as the technology evolves. Another consideration is the myriad perceptions: many dentists don’t trust the technology yet, they don’t believe the technology has been around long enough or is proven, and they don’t believe that that the accuracy could be equal to what they achieve with traditional VPS impressions. This author has heard more than a few dentists say, “These systems haven’t been around long enough, and I don’t want to pay to be a guinea pig for the technology.” The third factor that prevents a dentist from changing to digital impressions is simply avoidance of change. Dentists and assistants have learned and perfected the technique of taking traditional VPS impressions and have achieved mostly good results for many years. So a certain amount of comfort in the day-to-day routine exists, and change of any type can be anxiety inducing. The fear of a long, difficult learning curve with the transition to digital impressions and a general lack of knowledge about how easy the systems actually are to operate and how accurate the digital impressions are keeps some from going digital. When considering all these factors, it may come as no surprise why more dentists haven’t switched to digital impressions.
Examining the Facts
It’s productive to examine each of these factors and compare them with what the author has experienced throughout the years with the dental teams who send their work to the author’s lab, Ziemek Dental Lab, and have made the switch to digital impressions. First is the price of a digital scanner, which has been decreasing. Just a few years ago, the price of a digital scanner was typically $35,000 while today the average scanner price is in the lower $20,000 range. The 3MTM True Definition Scanner (3M ESPE, 3mespe.com) (Figure 1) is priced from $12,999, which is a significant reduction from its prior price point, and the iTero® from Cadent/Align Technology, Inc. (aligntech.com) (Figure 2) is now $24,999, which is also much less than a few years ago. The prices of these and other scanners on the market will continue to decrease as the technology evolves, making them more accessible.
The second factor is dentists not trusting the accuracy or reliability of the technology and doubting the accuracy of the digital scans compared with traditional VPS impressions. This author manages a dental lab that has completed approximately 50,000 digital impression cases and has seen firsthand the technology’s consistency and accuracy. The need for remakes from digital impression cases due to distortion or die trim errors simply disappears. Accuracy statistics vary among the competing systems on the market, and dental teams can contact the respective manufacturer for accuracy data on the particular scanner. The need for remakes due to distorted impressions and margin-trimming issues is eliminated with digital impressions because the dentist and assistant (as well as the patient) see the digital impression scan, including the prep, and opposing and adjacent teeth magnified on a screen chair side (Figure 3). If an area of the margin is not clear, they can rescan before sending the impression to the lab. With traditional VPS impressions, this is sometimes difficult to ascertain at the time of the impression and it takes a day or so for the lab to fabricate a stone model and trim the prep margin before an issue is identified. Typically at that point, production is put on hold and the model returned to the dentist to trim the die or verify the margin, and this can lead to an inefficient workflow in the lab and often a rescheduled seat date.
The same can be said for reduction issues and inadequate occlusal clearance with traditional VPS impressions because the digital scanner software shows the dentist areas with insufficient reduction, allowing the dentist to reduce those areas adequately before submitting the impression. If these issues aren’t identified with the patient in the chair, the restoration costs the dentist more in increased overhead because the dental team has to subsequently take time out of the workday to check models that have issues instead of being productive seeing patients, or the team must spend more time reducing the opposing or prep at the seat appointment. With a digital impression at Ziemek Laboratories, restoration fabrication begins as soon as the digital impression file is received. Most times the crown is 75% finished before the resin model arrives from the manufacturer. Even more impressive is that CAD/CAM technology allows a lab to fabricate virtually any type of crown from alloy-based restorations like full gold and porcelain-fused-to-metal to all-ceramic crowns and bridges without ever having a model.
The last factor this article is examining is the fear of a difficult learning curve and resistance to change itself. This is really about the general psychology of change and how we adapt as humans to changes in our lives. A quick examination of other technology in our lives that has gone digital provides a good perspective—music with iTunes and iPods, television, cameras and photography, calendars and scheduling software for home and office, patient records, radiographs, and much more. Have these new digital technologies enhanced our lives and made them easier, or has the learning curve been so daunting and cumbersome that they haven’t been practical? Obviously they have improved our lives or they wouldn’t exist. Imagine for a moment that you were still listening to your music on a cassette tape in a Walkman-type device with big bulky headphones and someone handed you an iPod or similar digital device with ear bud headphones and told you that not only was every music album you owned stored on the device but also every photo you every took, all your favorite video games, and a couple of HD movies were also on that device. Accessing the data is all done by the touch of the screen and if you want to find and purchase new material, you can do that from the screen as well without going to the store to purchase a new cassette tape. How difficult is it to learn to use this new technology? It varies slightly from user to user, but the goal of anyone who manufactures and sells digital devices is the ease of use so that the maximum number of people will purchase them.
Digital impression scanners are no exception. The manufacturers want the users to have an easy and successful transition to the new process so that more dentists make the switch and more patients experience the technology. Hands-on training is part of every sale, and ongoing customer and tech support is covered in the user fees. Dental assistants who are trained to use the scanners are integral to the successful transition from traditional impressions to digital because they can help improve workflow efficiency.
Another important aspect in the evolution of digital impressions is that open-architecture files are now becoming common. Open or closed architecture refers to the file type that is generated by the scanner and what can be done with that file after it is captured. In an open-architecture system, the scanner creates a digital file of the patient’s mouth that can be accepted by most of the laboratory CAD/CAM systems in use today. The most common file type is an STL. With that file, a tech-savvy lab can fabricate virtually any type of restoration (Figure 4). In a closed-architecture system, the scanner creates a file that is proprietary or only accepted by limited systems. This author strongly cautions against purchasing a closed system because it will limit the type of materials and restorations the practice can offer patients in-house.
Technology has evolved and helped craft a new future for dentistry. Everything is going digital, including dentistry. In this author’s opinion, this evolution is inevitable in dentistry.
About the Author
Jamie Stover, CDT
Tips for offices that want to go digital
• Research all available systems on the market and try at least your top two choices.
• Get your dental office’s lab involved early in the process. The dental lab should be a great resource for any material or technology that interests your team.
• Make sure your coworkers understand how going digital will benefit the entire team and patients. All staff members should be involved in the decision-making process.
• Make sure you are also trained on the system, if your state allows it. An assistant who can scan is an asset to a practice.
• Prepare for a learning curve, but don’t fear it and don’t get discouraged.
• Model-less fabrication of crowns is becoming more common.