Step-By-Step: Lava DVS

March 21, 2012

Many labs are involved in a digital workflow in one way or another. Those involved most likely agree that digital is undoubtedly the future of our industry. From hardware such as scanners and mills in our labs, to the digital acquisition of impressions from chairside scanners in dental practices, we are transitioning away from the old school and experiencing the advantages these technologies offer.

Many labs are involved in a digital workflow in one way or another. Those involved most likely agree that digital is undoubtedly the future of our industry. From hardware such as scanners and mills in our labs, to the digital acquisition of impressions from chairside scanners in dental practices, we are transitioning away from the old school and experiencing the advantages these technologies offer.

What is fascinating to me, and an interesting challenge, is the marriage of this new technology to the hand craftsmanship that is still so necessary to achieve beautiful lifelike results, while maintaining fit, strength and consistency. Herein lies one of the most challenging aspects of this new era: How do labs integrate new technology and materials into their current workflow and with their current technicians without causing turmoil, killing their bottom line, or sacrificing strength and reliability? At Ziemek Dental Lab, we do this by keeping it simple. We implement systems and technology that improve our workflow without sacrificing quality, strength, fit or esthetics, and that allow us to offer dentists a variety of restorative options.

The 3M™ ESPE™ Lava DVS Digital Veneering System is a great example of one such option, and is the best of both worlds. It’s a simple, effective way to take digital information and pair it with old school artisanship to deliver great looking, reliable crowns in less time, all while maintaining a healthy profit margin. This is primarily possible because the amount of hands on time required to finish Lava DVS restorations is minimal compared with a traditional hand stacked porcelain fused to zirconia crown, making it possible for technicians with little or no experience working with porcelain to get involved in the preliminary steps of fabrication, leaving more experienced techs with refining, stain/glaze and characterization.

What it is

Lava DVS is a Lava™ Zirconia core and a full-contour Lava DVS “top” (milled from the Lava DVS glass ceramic material) that are bonded with the Lava DVS Fusion Porcelain. These materials look like a hand stacked crown because the Fusion Dentin acts as both a bonding agent and a true dentin porcelain. It provides a rich chroma from within, while the Lava DVS top is a translucent material that creates the enamel layer.

This is not just marketing hype; the result truly is amazing. When you put a Lava DVS restoration next to a stacked crown and see how similar they appear in depth and translucence, it can be difficult to tell them apart. According to 3M ESPE’s research, its strength is equal to a restoration with porcelain layered over zirconia, while the bond strength of the veneering material to the zirconia core is excellent. Most labs have learned the importance of properly layering and firing porcelain on zirconia understructures to avoid chips, fractures and de-bonding. With Lava DVS this process is reduced to one main fusion cycle.

Case Study

Refer to the slideshow for figures

Most of the Lava DVS crowns we produce originate from a 3M™ ESPE™ Lava™ Chairside Oral Scanner C.O.S. scan (Figs. B and C), however you also can create these restorations on stone models with many of the same benefits to your workflow.

01 As soon as the Lava C.O.S/digital impression file is received, margin marked (Fig. D) and submitted for SLA model production, we split the file and simultaneously design both the Lava zirconia coping as well as the Lava DVS full contour “top” (Fig. E) and mill them both before the model arrives at our lab. The Lava DVS top mills in a “green state,” which allows you to do some contouring of the emergence profile and anatomy before you fuse it to the core, saving finishing time (Fig. F).

02 Because the zirconia core is designed specifically to fit the top with the 3M™ ESPE™ Lava Design Software, final finishing of the core is minimal and amounts to finishing the margins precisely and checking the fit of the core and the top.

03 Sandblast the Lava zirconia coping with 3M™ ESPE™ Rocatec™ Soft, a special material that delivers a mechanical and a chemical bond (Fig. G).

04 The next step is the fusion process and a firing cycle that accomplishes two things: bonding the core and top while completing a sintering cycle for the top. These steps easily can be completed by a less experienced technician. In fact, in our lab these steps are completed by a tech with no porcelain experience at all.

05 3M ESPE provides an easy to use chart that shows you exactly which Fusion Dentin to use for the requested shade. The Fusion Dentins and the Lava DVS tops are formulated to work together, along with the shade of the zirconia core to create the final desired shade/value. The key to this step is mixing the Fusion Dentin and the Fusion Liquid correctly, and getting the consistency of this porcelain perfect so you can evenly apply it inside the top and onto the core quickly and completely (Fig. H). Fuse multiple units of the same shade at the same time, making the most of the materials. This takes a few minutes, making it possible to fuse many Lava DVS crowns in a single shift.

06 Fire them in a porcelain oven that you already have; no special furnace is required. Let them cool and it’s on to refining the contour (Fig. I), correcting any voids between the core and top, adjusting occlusion and anatomy, then staining and glazing (Fig. J). A really nice aspect of the Lava DVS system is the Correction Porcelain that is used to fix any contour issues, contacts or margins after fusion.

What do you need?

That depends on whether your lab has the capability to mill the materials. Authorized Lava Milling Centers just need to purchase the Lava DVS blocks and the Lava DVS Porcelain kit. The Lava DVS tops can be milled in your current Lava mill as long as you clean it out before switching materials. If you are not an Authorized Lava Milling Center, you’ll need to decide if you will purchase the Lava zirconia cores and DVS tops un-fused and complete that step yourself, or pay a little more and purchase them already fused, leaving just the finishing steps to be completed in your lab. If you won’t be milling the materials in house, I recommend purchasing them already fused for a few reasons: fewer steps for you to learn and perfect; you can purchase just the Correction Porcelain instead of the full Lava DVS Porcelain Kit (which includes all the Fusion Powders/Liquids and Correction Powders available); and you won’t have to purchase the Rocatec Soft.

At Ziemek Dental Lab, we only sell DVS to labs fused. When fused correctly, the finishing process is simple. For this case, I started the finishing steps a few hours before the seat appointment, took the pictures while working on the case, and delivered it on time. The result was a good match to the existing A3.5 gingival/A3-ish incisal range of the adjacent teeth.

As you can see in Fig. L, the incisal third of No. 14 is lower in value than the A3 selected by the Dentist for No. 15, and although a custom shade would have allowed an exact match (the patient was not available for a shade appointment), the dentist did a good job selecting a close shade match.

This seat appointment took 5 minutes with no adjustments, making me, the dentist and the patient very happy. This is a case that labs see daily, not a once or twice a year “showcase” mouth, and a practical example of how we use the Lava DVS system to improve our workflow and offer dentists alternatives.

By combining the latest technology and old school craftsmanship we produce lifelike restorations that not only look beautiful, but also fit and function beautifully.

About the author

Jamie Stover is Manager of Ziemek Dental Lab, a high-quality fixed restorative lab located in Olympia, Wash. His focus is using his experience at the bench as a technician along with new technology and materials to provide dentists with highly esthetic restorations, while keeping them on the cutting-edge of dental technology. He can be reached by calling 360-943-6071 or by e-mailing info@ziemekdentallab.com.