Digital Impressions

By Marvin Berlin DDS, Gary Severance DDS, and Sherri White RDA CDD

Yes, the buzzwords in dentistry today are digital impressions; getting rid of the goop in the mouth, the potential of gagging and numerous other benefits for the patient and the dental team. But are there truly advantages to just capturing the information digitally that make it worth an investment? Unfortunately, several systems have been grouped together both in style and categories, and dental professionals should be aware of the differences and what each system can really offer. There are basically 1) acquisition units—or scanners only—Itero, LAVA COS and 2) Total Digital Solutions-E4D Dentist, CEREC 3D.

The Itero and LAVA COS systems both capture data. The data is then transmitted digitally to a model center (Itero mills their models; LAVA uses stereo lithography). In the case of the LAVA COS System, the information could also go to a coping/milling center (LAVA) for fabrication of a Zirconia coping. This is where the digital flow ends—the end result is back to conventional dentistry in the laboratory where the hard model is used just as it has always been and the restorative material is then built by hand or conventional methods. So, although these systems provide a valuable service, they don’t go all the way. Consider the perception of a capture only system versus the reality:

The perception is that you will not have to take a conventional impression in the mouth, but instead you have scanning device in the mouth for a period of time scanning the area.

The perception is that you get rid of the $10 cost of taking a VPS impression— but in reality there is a surcharge of $20+ for each scan series by both manufacturers to the dentist and in addition the laboratory is charged $25–$40 for the model that is fabricated depending on the complexity of the model.

The perception you won’t have to use UPS, FEDEX or any other method to ship your impression, but the model has to go to the lab via conventional shipping methods and then final restoration still has to be shipped back to you.

And finally, no more disinfecting the impressions prior to sending to the lab—it’s digital—but don’t forget after each patient you’ll have to disinfect/sterilize the wand that was used intraorally.

So the capture-only devices sound good, but more for marketing purposes and competitive claims than anything else add to that the $20–$25,000 price tag along with a per use charge, and it is a significant investment for eliminating only one step—the impression. Unless this type of system (acquisition units) can be combined with a total solution with design center (full contours) and mill capabilities both chairside and through laboratories, they don’t offer the complete solution that dentistry is looking for, now and in the future.

The real benefits and advantages come from going to one of the total restorative chairside solutions—to not only be able to complete digital impressions, but then to design and mill full-coverage, single-unit restorations right then and there— and offer SAME-DAY DENTISTRY. In previous issues of Sidekick magazine—we’ve spoken of the numerous advantages to the practice, the patient, the team and even to the health of the tooth with preparations that are restored the same day. Here we’ll emphasize the true benefits and potential of digital impression systems combined with a restorative milling solution in the office with E4D Dentist. There are two full contour chairside systems available—the CEREC System by Sirona Dental was introduced over 20 years ago and utilizes an image system that requires a complete contrast of the operative site—therefore requires application of a powder or spray to completely cover the area intending to be scanned. The other system, the E4D Dentist System, uses laser-based scanning to capture the intraoral conditions in its true state and can also scan impressions, bite registrations, and models without the use of powder or a contrast agent. In fact the E4D Dentist System is so versatile that it is the only digital capture system that has Three Source Scanning (TSS).

The real benefits to the patients, the practice, and the bottom line is the total solution of E4D Dentist and its powder-free Three Source Scanning options.

It can scan intraorally, it can scan an impression (even alginate) and, then if needed, scan a model and from anyone of those generate the same virtual model. So it allows you to immediately adjust to the clinical conditions and choose your preferred method while all still offering a Same-Day Solution. What does that mean to you and your practice? You are in control at every step and can adjust as necessary. Consider the following situations.

Scenario #1–Patient arrives for a simple crown prep and seat in same appointment. You prep the tooth using the all ceramic protocol of adequate clearance, rounded internal angles, visible butt joint margins. The prep is complete and the patient and prep is ideal for intraoral scanning. Simply clean and dry the areas, capture the scans, have the patient close and go on with the design and mill. Try-in of the final restoration is done right in the mouth and then it is seated—all in one appointment.

Scenario #2–Patient arrives for simple crown prep and seat in the same appointment. After prepping the tooth and starting to scan, the area is difficult to keep isolated, the patient’s mouth opening is small and there is a struggle keeping the wand in the ideal location. Simply tell the patient you are going to take a quick setting impression— alginate or VPS and in a couple minutes, pull the impression have the patient close and then you have the impression to scan, invert, and begin the design process followed by milling. Again seated in one appointment in the same time it took for scenario #1.

Scenario #3–Patient arrives for a simple crown prep, and will need to come back for the final crown later due to her schedule—so she’ll come back later in the day—or even tomorrow for the final, but she needs it before the weekend. Prep is completed, an impression is made and using quick-setting, single-use stone (EarthStone, Tak via Henry Schein), the assistant pours it up and dismisses the patient with a temporary. Knowing that having the patient in a temporary for only a couple hours or even a day will minimize any occlusal changes or shifting of the teeth as well as sensitivity from exposure to bacteria or debris this is an ideal solution especially for a two-appointment schedule. During a break in the day’s schedule, the assistant scans the model and the bite (triple tray) and after designing and milling does a try-in on the solid model to confirm fit and contours, then stains and glazes and has the restoration ready for whenever the patient returns.

All of these scenarios are possible with the E4D Dentist, Same-Day Dentistry—or Dentistry that you control—with many possibilities adapting to the need of the practice and the patient. Although digital impressions are the wave of the future, this is only half the story. The real benefits to the patients, the practice, and the bottom line is the total solution of E4D Dentist and its powder-free Three Source Scanning options.