Inside Dental Assisting
Successfully Integrating Digital Impressions into the Practice
Achieving success calls for an awareness of the challenges as well as the benefits of going digital.
Managing a dental laboratory that has handled over 10,000 digital impression files provides valuable insight into how and why some dental practices thrive with the addition of a digital oral scanner and experience all this technology has to offer, while others have a ponderous and frustrating experience, with scanners ending up unused. To help practices achieve successful integration of a scanner, this article outlines some of the benefits of this technology, clears up some of the misconceptions, and pinpoints key tips for dental assistants—in addition to detailing some factors that can impede success. Dental assistants can be essential in this integration process, especially in states where expanded function dental assistants may take final impressions. In some practices, dental assistants scan all the teeth included in the impression and leave the preparation for the dentist to scan and submit. In other situations, the assistant scans all the teeth including the preparation, or dentists complete the entire scan themselves. The versatility of this technology allows the practice to obtain successful digital impressions in a number of efficient ways (Figure 1, Figure 2, Figure 3 and Figure 4).
Does it Work?
Digital impressions provide incredibly accurate data, often resulting in restorations that fit so well, many digital dental offices experience 5 to 10 minute appointment times for crown seats. This level of accuracy can dramatically change the workflow of a practice while also reducing its overhead.
Many of the same key factors that apply to a successful crown delivery originating from a traditional impression also affect a digital impression. This process begins with a quality preparation and adequate retraction of the gingival tissue, and continues through to the dental lab’s knowledge of how to work on the resin models (as opposed to traditional die stone). Dentists or dental assistants can take excellent digital impressions, yet still experience frustration with the fit during the seat appointment when the lab does not understand how to work with a different medium.
Benefits of Going Digital
A digital scanner benefits a practice and improves the workflow between the dental laboratory and the dental office in a number of ways. First is the elimination of die trim issues. With a traditional impression, when the lab cannot see the margin clearly, it is sent back to the dentist, who must recall the patient from 3 or 4 days earlier and then trim that specific area of the margin accurately. Under these circumstances, production on the case is delayed, possibly requiring a reschedule of the seat appointment. With a digital scan, the dentist and assistant see the margin in full-screen, 360°, and even 3-D detail, and can be confident that the margin is clear and the preparation design is exactly what is desired.
Another digital benefit is eliminating failed cases due to distorted impressions. The dentist and assistant see the entire impression on the screen in the form of a virtual model, which can be viewed from every angle and in centric relation with the opposing arch to verify that the bite recorded is accurate as well. In addition, dentists and assistants can view the preparation and impression instantly, and know what they are sending to the laboratory immediately, in contrast to waiting a few days for a stone model.
For most digital practices, crown seat times are decreased. When dentists and assistants become proficient at scanning and are working with a dental laboratory that is also capable working digitally, the fit of the crowns improves significantly. Studies have shown that when a dentist scans a prepared tooth and also takes a traditional impression of the same preparation to compare the fit of the final restorations, 83% of the time the dentist will choose the restoration that was made from the digital scan.1
Digital scanning enhances the image of the dental practice in the eyes of patients, who welcome the way technology improves their experience. Offering patients an alternative to having a tray of impression material in their mouths for 5 minutes is appreciated. In addition, patients are pleased to view their tooth in 3-D on a screen chairside. The perception that the dentist, assistants, and staff are using the very latest technology increases their confidence and comfort level in their provider. This technology may even be the basis for new patients who are aware of digital impressions.
A dentist and dental laboratory can have a coast-to-coast transfer of digital data and finished restorations with no die trims, distorted impressions, or delay in seat appointments—and crown-seating chair time faster than what the dentist may experience with traditional impressions.
Making the Leap
The offices that experience the most success with digital technology all appear to share one important trait: The team is 100% committed to making the switch to digital and working through the transition process together.
In addition to the up-front cost of the scanner, there is a learning curve when moving from traditional impressions to digital scanning that should not be underestimated. It is recommended that the dentist or lead assistant broach the topic of purchasing a digital scanner at a staff meeting to gauge the interest level among the entire team. Whether the practice has a remake percentage higher than it should be due to impression issues such as distortion or unclear margins should also be discussed. At this time, the team should also review the local market as it relates to their type of practice and consider whether other offices in the area are offering digital impressions. Digital scanning can be an effective way to set a practice apart.
Lack of support from the dental staff or from the dental laboratory can create challenges for the practice attempting to integrate digital technology. Including the entire staff makes a significant difference, because many of them will need to use the scanner, which is not a completely intuitive process. While scanner manufacturers usually offer enough in-house, hands-on training with the purchase to get the users started, additional practice is necessary to become proficient. It is therefore important to discuss which assistants will be involved in the scanning process.
As for the dental lab, it should also become involved early in this process. The practice should ascertain if the lab accepts digital impressions, and if so, from which scanners. Labs can and should be a great resource for the dentist and staff when it comes to the new materials and technology available. Progressive digital laboratories are currently accepting scans from the major scanners on the market: 3M ESPE (www.solutions.3m.com), Cadent (www.cadent.biz), and Sirona (www.sirona.com). Manufacturers offer tiered entry levels of access for the dental lab, which range from a minor investment for the ability to work on a practice’s cases, to higher levels of financial commitment and access. Individual labs decide at what level they want to be involved; however, labs should support their client dentists and be able to provide virtually any type of restoration from whichever scanner their client purchases.
A common misconception is that it is only possible to obtain a CAD-designed restoration using a digital impression. While this type of restoration may be produced slightly more quickly from a scan, virtually any type of restoration can be created—from porcelain-fused-to-metal crowns and gold onlays to all-ceramic crowns (Figure 5). One reason some labs choose not to become involved is the model cost. When labs work with a digital case, they do not create a stone model in-house, and must pay the manufacturer $16–$35 for a resin model. Labs that are efficient with the digital workflow know that these costs can be offset by a streamlined workflow and all of the previously mentioned factors—eg, no die trim issues or remakes due to distortion. It is important to find out if the laboratory being used is capable and willing to work with the dental practice through this transition.
Once the practice decides to make the switch from traditional to digital impressions, the dentist and any available staff should attend a seminar or trade show that showcases the different systems available. The digital scanners on the market all provide good results, but there are differences between each system such as price, scan fees, maintenance agreements, powder vs. non-powder, the ability to mill in-house, size of wands, and scanning technology. Attending a seminar or trade show that showcases digital scanners allows a dentist and staff to experience the scanners and compare all these features to see which one best fits the practice. Once the choice is narrowed down, most of these companies will do in-office presentations for a prospective buyer, giving dentists and assistants a more comprehensive demonstration, and another excellent opportunity to involve their dental lab in the process.
Tips for Success
Before the Scan:
- Pre-enter the patient’s information into the scanner before the appointment to streamline the process.
- Assess the patient for a sensitive gag reflex, low palates, strong tongues, and tight lips that may create challenges.
- Prepare the patient. Discuss the benefits and the process of the new digital impression technique, using any patient informational videos or literature provided by the manufacturer.
During the Scan:
- Gingival retraction—When cord is pulled, make sure the margins are totally clear. Be prepared to touch up packing, as even individual cotton fibers hanging over margins can interfere with the scan accuracy (Figure 6).
- Field control—A dry environment is key.
- Keep the area clear by using a system such as Isolite (www.isolitesystems.com) (Figure 7), OptraGate (Ivolcar Vivadent, www.ivoclarvivadent.us), or similar device, along with cotton rolls to keep the lips and tongue clear of the scan tip (Figure 8).
- Keep bleeding under control by syringing a hemostatic agent such as ViscoStat (Ultradent, www.ultradent.com) into the sulcus, and also soaking the cord with a hemostatic agent such as Hemodent® (Premier Dental, www.premusa.com) (Figure 9).
- Keep the scan path clear. Know where the scanner tip is heading and use a mirror to clear tongue, lips, and stray cotton rolls (Figure 10).
Proactive research, a fully committed dentist and staff, and a dental laboratory that supports the digital workflow are all key elements to successfully integrating this technology in a practice and achieving success.
Figure 3 and Figure 4 are courtesy of Gordon Yamaguchi, DDS, and Garret Yamaguchi, DDS, of Yamaguchi Family Dentistry, Olympia, Washington. The author would also like to thank them for the scanning tips they provided, and as well as Jessicah Whipple, EFDA, from the office of Jon C. Walker, DDS, of Olympia, Washington, for the scanning tips that she provided.
1. Christensen GJ. Will digital imaging replace VPS impressions? Clinicians Report. April 2010:2.
About the Author
Jamie Stover, CDT
Member, Laboratory Alliance of the American College of Prosthodontists
Ziemek Dental Laboratory
Ziemek Milling Center