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Programat CS6: Next-generation vacuum furnace for ceramics and Zirconia

By James Klim DDS, FAGD, AAACD

A s a technology-driven practice for the last two decades, we have experienced many bene ts in clinical delivery systems that keep evolving and improving our clinical work ow. First and foremost was the introduction of in-o ce CAD/ CAM. en the progressive upgrades of di erent generations of intraoral scanners and milling machines. Each upgrade has provided clinical pro ciency and predicable quality, rewarding each day of practice. is article will introduce the next generation furnace, the Programat CS6, designed for the productive CAD/CAM o ce. It is an all-in-one furnace that introduces vacuum technology for both ceramic and zirconia cycles. e CS6 furnace drop-down ring chamber design optimises the drying cycle to generate a super-speed IPS e.max CAD crystallisation cycle of just over eleven minutes. e drop-down ring chamber design allows hot air to rise from bottom to top, so the stain and glaze liquids move up and out, signi cantly speeding up the drying time for crystallisation and glazing cycles. e large 55mm ring chamber enables crystallising 4 IPS e.max CAD restorations at once, and any bridge milled from B45 blocks. e zirconia fast cycles are vacuum assisted, using a vacuum pump to remove air from the chamber during the densi cation cycle. Trapped air is removed from the pores and therefore the counter pressure of the trapped gases to the

Sintering oxygen technology stabilises colouring ion for lifelike aesthetics

sintering is reduced. is will result in less defects and pores in the microstructure. Defects will scatter light and result in more opaque zirconia. By removing the air pockets during the sintering process, the resulting sintering zirconia is more translucent and aesthetic. 1 In the nal sintering phase, fresh oxygen is pumped back into the chamber, stabilising the zirconia colouring ions (A-D colours), improving nal hue and chroma. Oxygen generates a stable colouring process for the zirconia colouring material and provides lifelike aesthetics. 2 e author has observed similar translucency achieved in 3Y high strength zirconia; 22 minutes with the CS6, comparable to a longer 9 hours plus cycle in traditional zirconia furnaces. e CS6 furnace can be programmed for third-party zirconia brands, ceramic, and glazes. Independent of the CAD/CAM milling volumetric data, the sintering program can be used with unlimited sintering cycles and up to 3 zirconia restorations can be red with a single cycle. Besides the Ivoclar recommended programs factory-installed, 60 individually adjustable programable cycles are designed for up to three heating and two cooling stages. is furnace is genuinely a universal furnace for all brands of ceramics and zirconias. e pre- ring work ow for an IPS e.max CAD crystallisation in the Programat CS6 is similar to what we now do in our CAD/CAM clinical theaters. Preparation for success starts with an emphasis on adequate occlusal reduction with 1.0 minimal thickness plus the virtual spacer. In most clinical situations, the author will reduce 2-2.5 times the minimal thickness

of the chosen clinical material. Adequate occlusal reduction for restorative type will ensure software optimal morphological design and strength assets needed for the engineering and longevity of the restoration. Relative to bur size and milling speed, the author uses the 100um margin (this may require manually changing margin thickness to 100um in the design screen depending on software version) parameter to optimise the marginal mill. For thinner veneer restorations, an extra ne milling setting will precisely mill thin margins with themargin thickness parameter set to 50um or greater. Both of these milling approaches provide precise, clean IPS e.max CAD margin quality with no microchipping from the machining process. Once the restoration(s) are machined, the pre-crystalised nishing process is completed. e restoration intaglio surface is lled with Object Fix Putty/ Flow with an IPS e.max optimised ring chamber appropriately sized die pin for the restoration(s), and glaze/stain applied when desired for the case. ere is a new crystallisation tray designed for the Programat CS6 and must be used for IPS e.max CAD ring. Place a maximum of four crowns or one bridge on

IPS e.max 11 minute cycle

IPS e.max optimised firing chamber

80 AUSTRALASIAN DENTIST