Is CAD/CAM just a craze?

If dentistry was undergoing its greatest advancement in half a century, would you necessarily notice? You probably remember exactly where you were when you heard about September 11. But can you remember when you first thought, hey! - titanium is an OK substitute for a root? It's the same with NiTi, for endo and polyvinyl instead of Thiokol polyether for impressions. In dentistry, we have no way of knowing when a radical new procedure suddenly becomes ordinary and normal.

CEREC is 20 years old. Early adopters might have raved about it, but mainstream dentistry generally dismissed it as a cult. In 2007, the marketplace has taken notice and machines that mimic CEREC are the sign of an industry voting with its feet. But will the mainstream dentist take notice?

When the computer gamer industry pushed the development of accelerated graphics cards and true 3D imaging arrived, CEREC reached a new level of acceptancebut it's a truism to say the majority of dentists are still to embrace CAD/CAM, although as the CRA report points out, you might be using it but not know about it.

Since achieving 3D virtual modeling with real-time milling, Sirona Dental Systems has invested millions more euros, simplified the design process by shifting many of the restoration surface contouring decisions away from the dentist. Recent advances have meant the software does more and the dentist does less: after all, that's what's computerized dentistry should be all about. CEREC produces a bespoke restoration for every patient, every time, unlike many repetitive industrial processes that use CAD/CAM.

These improvements came about through the efforts from code crunchers in the company, academic researchers and beta-testing dentists all over the world, taking CEREC to a higher "intelligence level."

This year's Biogeneric Program takes information from remaining tooth structure, and uses digital tooth morphology from a database of 400 digitized teeth. It 'custommorphs' the new restoration to accurately fit not just a 'robot' tooth, but to your patient's own tooth in an intimate and seamless way - truly a 'restoration' of what had been lost.

You can even use information about opposing teeth to digitally refine the occlusal surface before starting to mill.

If dentists like you haven't taken notice, dental manufacturers have. Numerous companies have recognized that crown and bridge impressions of today have a use-by date. Optical impressions will become the new standard. Many other products have been successful in the laboratory sphere but CEREC remains the only commercially available chair side CAD/CAM product in the industry.

There are benefits that have trickled down to non-CEREC users as a result of the last twenty years research and development. There are some unique and interesting protocols created to complement further growth of the CEREC chairside and laboratory systems. For instance, instead of using them to create a virtual model chairside, optical impressions can be e-mailed to a lab. Here, the restoration is designed, milled out of a block of resin, invested, and cast into a gold restoration for return to the operator. Other notable advancements have been the introduction of restorations which use advanced materials specifically manufactured to undergo secondary processing after cold-milling, to obtain stronger ceramic crowns and onlays which retain high esthetic qualities. To date, the materials for chair side use were limited to feldspathic or leucite-reinforced cold-milled ceramics; these were easy to stain and glaze or just simply polish. We now have access to a lithium disilicate material, which can be heat-processed chair-side, has a strength that's three times greater than the former materials, with an uncompromised esthetic outcome. Ivoclar, the manufacturer of this EmaxCAD product claims that these can even be luted instead of bonded, eliminates one of the most clinically-sensitive procedures in the field of dentistry.

There's no question that the general practitioner will eventually recognize the potential for CEREC in his or her practice. While many long-time users no longer benefit by being "unique' or on the "cutting edge" because so many of their colleagues are now using the same product, newcomers always notice that single-appointment dentistry coupled with the fact that we are a service-driven industry ensures professional growth in a competitive marketplace. The financial benefits of fixing laboratory expenses over the period of a long lease has a tremendous impact on any business model even though most dentists don't recognize this until long after they have integrated the machine into their practices.

Still not convinced?

Anecdotally, as a profession we know that immediate bonding allows maximum conservation of the most tooth structure: we reached that conclusion last century. However, we also recognize that in most large cavities, composite resin just isn't adequate. One of the most underrated benefits of CEREC-style dentistry is the concept of definitively restoring the remaining tooth structure minutes after it has been prepared by our handpiece. There is tremendous body of evidence that immediate dentin bonding needs to be the norm: the next logical step is to immediately restore the preparation to completion. Many users but perhaps more importantly many, many patients have reaped the benefits of applying this concept.

The only question that remains is whether the mainstream dentist can afford not to take notice!