Virtues of Virtual. ForwardTrends. Digital Impressions \\\\ 12 dentallabproducts August 2008 dlpmagazine.com

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1 ForwardTrends Digital Impressions \\\\ Virtues of Virtual Digital impression-taking systems and electronic data transmission to change the model of dentistry. By Richard Palmer Photo: Getty Images 12 dentallabproducts August 2008 dlpmagazine.com

2 Trends Forward //// Digital Impressions Creating dental restorations conven- patient-specific abutments. Impression-taking and model- Both the D4D and the CEREC systems also allow the tionally has always been a very tactile, hands-on, physically prepping procedures include unpleasant, time-consuming, dentist to design and fabricate inlays, onlays and full-contour laborious process for both the dentist and laboratory techni- costly, and hazardous processes that would be eliminated if single-unit ceramic restorations directly at chairside while cian. From impression-taking to hand-pouring the model to the entire process began with digital impressions. the patient waits in the office. However, until recently, the porcelain buildup, each step in the process requires touching and examining a physical representation of the case. Four digital impression systems are available now for chairside use: CEREC (Sirona Dental Systems), Lava Chair- use of these acquisition and milling units was limited to these type of select cases. Today, with the advent of digital impression-taking sys- side Oral Scanner C.O.S. (3M ESPE), itero (Cadent), and E4D The goal of chairside systems has been to get the patient tems, Internet portals, and CAD/CAM technology, some (D4D Technologies). Comprised of a handheld acquisition in and out very quickly and not have to come back, said traditional physical fabrication steps have gone virtual. New unit for capturing tooth prep data (i.e., digital impression) Lee Culp, CDT. Founder of Mosaic Studio dental laboratory advancements in digital technologies are now available that and a design module, each allows the dentist to instantly see and the Institute of Oral Art and Design teaching facility could one day eliminate not just the use of physical impres- the three-dimensional digital tooth prep on the computer (now part of the Dawson Academy), Culp also has been sions but in select cases the very models technicians use monitor in a positive configuration (versus the negative instrumental in bringing the D4D system to market (see every day, creating a new virtual world of dentistry. format of a traditional impression). After reviewing the 3D On the cusp sidebar on page 15). The system gives the prep image, the clinician can adjust the tooth prep, if neces- general dentist an addendum to his workflow where he can First Step First sary, capture a new image right then, and send the digital do a single crown or a couple inlays fast and easy. For the most part, digital dentistry in the lab currently is impression files electronically to a laboratory equipped With the ability to now use the chairside system for digi- limited to the scanning of a poured model to digitally capture with the compatible laboratory component (D4D expects tally capturing intraoral data and sending case files the labora- physical information, which is then used in the virtual design to introduce a lab component early next year). When the tory, the role of the chairside system is greatly expanded. Dr. (CAD) and manufacture (CAM) of restorative substructures, laboratory receives the data, the two parties can consult in Roger Briggs has used his CEREC 3 chairside unit at Briggs such as zirconia frameworks, wax patterns for pressing or real-time on the case, make further adjustments as needed, Family Dentistry in Scottsdale, Ariz., since the upgraded sys- casting, all-ceramic full contour crowns, implant bars, and then proceed with the restorative case design. tem was launched several years ago. We probably do maybe Starting off Working with the CEREC Connect system, Cody Iverson, G.M. of Iverson Dental Laboratories, creates a cutting-edge restoration without a model, going from virtual to reality. Fig. A Fig. B Fig. C Fig. D Fig. G Fig. H 1. The lab receives the electronic prescription from the doctor with the digital impression image (Fig. A) and prescription information. 2. The virtual model is trimmed to replicate a working die and the margin marked using the automatic margin finder (Fig. B). 3. From an anatomy library, the technician selects the design of the tooth to replicate adjacent teeth (Fig. C). 4. Through virtual grinding, the software adapts the crown to the model, adjusting contacts and occlusion to specified parameters (Fig. D). 5. In the final milling preview, the last adjustments and directions for milling the crown are completed (Fig. E). 6. The crown is milled out in the blue partially crystallized state. (Fig. F), then fired to finish the crystallization process (Fig. G). 7. The crown is stained and glazed, prepared for cementation (Fig. H), then sent to the doctor for seating. Photos: Cody Iverson, Iverson Dental Laboratories. Fig. E dlpmagazine.com Fig. F August 2008 dentallabproducts 13

3 ForwardTrends \\\\ Digital impressions 15 cases a month of single-unit, right-then- cases, Dr. Briggs can now digitally capture the launched in February 2008, send the scan options and a much wider range of restor- and-there, let s-get-it-done work, he said. case and through Sirona s CEREC Connect data to a laboratory for design, milling, and ative materials. The broadened capability of But for the more esthetic cases or larger Web-based communication system, which finishing of a broader range of restorative the system also frees Dr. Briggs and his staff to focus on the practice. Prepping and cementing is still the best use of Dr. Briggs time, said Rick Durkee, CDT, owner of Lafayette Dental Laboratory in Phoenix, who is on the receiving end of Dr. Briggs CEREC Connect case transmissions. I see it as giving him flexibility, he added. With as busy as his office is, it makes more sense for him to use the CEREC Connect. keating junior See us at the XXX Meeting, Booth XXX. Use XXX on card or at For sales visit, circle XXX on card. The Model-less Model Digital impressions and case transmission moves technology-driven labs further into the digital domain by offering the ability to fabricate full-contour single-unit restorations without a model. Removing the model entirely from the fabrication process not only shortens the overall turnaround time, but also eliminates such negatives as dealing with the dust associated with model trimming as well as the inconsistencies created by material shrinkage/expansion. However, without the model, there is no checking the fit, contacts, and occlusion until the patient is back in the chair. Dr. Briggs compares the experience of model-less dentistry to walking out on the Grand Canyon Skywalk, which allows visitors to walk on a clear glass platform that extends 65 feet out over the edge and 4,000 feet above the floor of the canyon. However, he said that the fit is usually comparable, if not better, than a porcelain crown created on a model, requiring little adjustment prior to seating and cementing. The key is getting the initial digital impression, which requires the same standard learning curve associated with any new technology. Durkee commented, It s a little out of the comfort zone not to have a model, but it s a work in progress and we re getting better the more we do. It seems to be working extraordinarily well. Iverson Dental Laboratories in Riverside, Calif., also is registered on the CEREC Connect Web portal ( General Manager Cody Iverson said the lab signed up when the system was first launched but just received its first digital case in July (see Starting off sidebar on page 13). It s just a matter of getting dentists on board, he said. He attributes some of slow start to dentists not thinking outside the box. They ve got the CEREC, and they re milling inlays and onlays in-house. Our job as dental technicians is to show them the bigger picture and enlighten them to the complete benefits, said Iverson, referring to milled full crowns and larger restorations. They re not concerned about the fit because of no models. 14 dentallabproducts August 2008 dlpmagazine.com

4 The benefits include everything from fit and marginal integrity to less adjustment to cost. For now, fabrication of restorations that are entirely digital until the milling with no models is limited strictly to full-contour single units, mostly posterior, without any substructure. Anything full contour can be made without a model, said Culp. As soon as you go to a coping, you have to have 4.1% GPs using an in-office digital impressiontaking device to have a model because you have to have contact and occlusion. Trends Forward //// digital impression porates stereolithographic (SLA) or milled resin-polymer models, or plans to in the future. The world is not really ready for model-less dentistry, said Culp. The technology right now in digital is way ahead of the acceptance curve. Instead of forcing people into what we feel they should be doing, we ll let them evolve into what they want to do. By providing the option of models, the manufacturers allow technicians to set their own comfort level but still keep conia coping, and press to it. So, you could get rid of the the door open into advanced technologies. File splitting But that certainly doesn t limit the number of units that models by pressing over a preprinted, computer-designed also is an integral part of the 3M ESPE and Cadent model- can be produced. According to Culp, these systems allow wax pattern over a zirconia coping. If everything is done based digital systems. After approval of the digital model the clinician/technician team to handle cases involving the properly you don t need a die. design, with margins marked and dies trimmed virtually, restoration of multiple teeth simultaneously. You can do To get over the mental hump of the model-less zirconia the model data is sent electronically to a central facility for an 8-unit case. Scan it all, send it, design it, have it all milled crown, Culp concedes that dentists and technicians like the fabrication of the physical model while the lab simulta- out, and with the accuracy to go to full contour without a Dr. Briggs and Durkee need to take a leap of faith over neously continues with the design of the restoration. With model, he said. the canyon s edge in the precision of digital technology. the Lava C.O.S. digital model, the digital technician can Culp adds that with file splitting technology, a design can If everybody trusted the systems and trusted CAD/CAM, design a zirconia framework that can be sent to a Autho- include a milled zirconia coping topped with full-contour we really don t need models for doing most of what we do rized Lava Milling Center for milling or to one of 3M ESPE s pressed anatomy. You can take the digital information to in dentistry, which is single units. selectively open manufacturing partners. Likewise, the make a zirconia coping, and as you sent that data to your itero data can be sent to a CAD/CAM system compatible milling center, you would also send data to a processing Not there yet with Cadent technology, such as Wieland s Zeno system. center to have a wax full-contour restoration printed at To accommodate those who are ready to accept digital den- After both model and structure are completed, they meet the same time that would go over the zirconia coping. You tistry but still prefer or need the double-check afforded by together at the lab bench, and the technician continues would take the full contour wax pattern, fit it over the zir- models, each of the digital impression systems either incor- with traditional hands-on methods. On the cusp Fig. A Fig. B The recently launched E4D system allows the dentist to scan, design, mill, and seat metalfree single-unit restorations in one visit, with future lab designing and milling components set to expand available options to the practitioner. 1. The teeth are prepped for the restorations (Fig. A), and the digital impression is captured using the acquisition unit (Fig. B), guiding the user through the imaging procedure (Fig. C). 2. The impression and prescription data are sent electronically to the lab for analysis, consultation, and approval (Fig. D). 3. The user can move, rotate, and expand the image on-screen during the design process (Fig. E). 4. The single-unit restorations are Fig. C Fig. D milled (Fig. F), stained and glazed, and baked. 5. The teeth are prepped for seating (Fig. G), and the restorations are cemented into place (Fig. H). Photos: Lee Culp, CDT, MosaiC Studio Fig. E dlpmagazine.com Fig. F Fig. G Fig. H August 2008 dentallabproducts 15

5 ForwardTrends \\\\ digital impressions FOUR ON THE FLOOR C a d e n t 3 M E S P E Though similar in appearance, the digital impression systems currently available for the capture of intraoral surface data are designed to help streamline production and heighten communication accuracy and expediency between clinician and technician. The Lava Chairside Oral Scanner C.O.S. from 3M ESPE ( and Cadent s itero (www. cadentitero.com) center around the manufacture of a durable resin polymer model, while the E4D from D4D Technologies ( and Sirona Dental s CEREC and inlab systems ( offer model-less dentistry. However, all four system plan to provide labs with the option of working with CAD/CAM-produced model or model-free. To reduce turnaround time further and provide a bit more control over the process, Cadent is looking into a business plan that would allow high-volume labs to incorporate an on-site model-making system at their facility. Although it now is essentially a model-less system, Sirona plans to incorporate SLA models into the CEREC system by February According to Norbert Ulmer, Sirona Director of Laboratory CAD/CAM, We believe that it is important to be able to offer physical models to our customers. At the same time, we also feel very strongly about the cost and time saving aspects of model-less dentistry. Moving in the other direction, the modelbased Lava C.O.S. system is offering a modelless option. According to Brian Keenan, Marketing Manager for the Lava C.O.S., For those labs who want to go model-less, 3M ESPE has new technologies in the pipeline to make that a reality. D 4 D S i r o n a 18.4% GPs with digital impression systems on their wish lists. DLOAC junior 1/2 H See us at the XXX Meeting, Booth XXX. Use XXX on card or at For sales visit, circle XXX on card. Gearing up Before model-less dentistry can grow into a viable option for labs, dentists need to get the digital impression acquisition units into the operatory, which may happen sooner than later. When asked in the June 2008 Dental Products Report Technology survey¹ about technology purchases, 4.1% of responding GPs said they currently own a digital impression-taking device, and 18.4% plan to purchase the high-tech unit in the next 12 months. That s a potential of nearly onequarter of U.S. practitioners with the ability to take digital impressions and needing labs to send the data to. We need to have the dentist system first, said Culp. And we need to have enough out there so when we do go to the labs, they have a market already developed for them to talk to. In order to talk to as many dentists as possible, both Lafayette Dental Laboratory and Iverson Dental Laboratories plan to incorporate multiple systems into use. I want to position my lab to be able to accept digital impressions of all types, said Durkee. lab References 1. The June 2008 Dental Products Report Technology Census survey was ed and direct-mailed to 3,216 GPs in the United States; 444 completed surveys were returned for a response rate of 13.8% 16 dentallabproducts August 2008 dlpmagazine.com