The sunny side of CAD/CAM
Everything seems to be going digital. Photography. Music. File Storage. Even dental labs, which will benefit patients as well as the dentists who serve them. As the materials and technology available for CAD/CAM dentistry have improved, so too have the restorations patients can receive from this form of digital dentistry. Today's CAD/CAM restorations are better-fitting, more durable and more natural looking than previously machined restorations.
CAD/CAM technology should not replace the skills needed by a dentist or dental laboratory technician. Dentists must be accurate in creating the initial tooth preparation; both dentists and laboratory technicians must be accurate when taking the digital impression and creating the restoration.
There are many benefits to CAD/CAM dentistry, including:
Improved turnaround times
With CAD/CAM technology, dental technicians can quickly tell if a bite is off or a margin is inaccurate. They can then immediately contact the dentist and ask for a new file or impression. With real-time troubleshooting capabilities, remake percentages are lowered dramatically.
“Using our CAD/CAM technology, we are able to save our clients time and money,” explained Rick Brewer, CDT, Sun Dental Labs’ lab manager. “With our software, we can tell instantly if the fit of a crown and bridge is correct. If it isn’t, we can get in touch with the doctor right away for a new model or file. Ultimately, we want to deliver a crown or bridge that doesn’t require any chairside adjustments.”
Milling equipment is typically accurate to 50 micrometres, CAD/CAM dental restorations are comparable in fit to traditionally fabricated dental restorations. Accuracy is critical, particularly since the fit of a restoration is the key to preventing future tooth damage. For example, an ill-fitted crown can leave space between the teeth, or between the tooth preparation and the restoration, which could lead to an increased risk of infection or decay.
Better long-term patient results
Since these types of restorations contain no metal to block subsequent x-rays, dentists are able to keep track of potential decay underneath a full zirconia restoration whereas conventional PFM or traditional gold crowns block x-ray radiation, disallowing such an evaluation over time.
As CAD/CAM enables dental practitioners to seat a finished restoration in a week’s time, practitioners find that treated patients have fewer side effects like tooth sensitivity following their dental treatment.
Sun Dental Labs goes digital
With the introduction of CAD/CAM to the dental industry, laboratory personnel must now become computer whizzes who machine single-crown or multi-unit bridge restorations and, when necessary, layer or press the veneering porcelain to the CAD/CAM copings as well as impart esthetic characterizations or final contouring to the restorations.
According to Edward McLaren, DDS, MDC, “All normal, basic and repetitive procedures will disappear and be replaced by CAD/CAM. In the not-too-distant future, most model work for single- or two-tooth restorations will be completed by CAD/CAM, since dentists will most likely incorporate digital impression taking. When traditional models are used — which will also be generated by CAD/CAM — they likely will involve multiple teeth, or cases requiring occlusal adjustments.”
Enhancements to the milling technology itself have given rise to more accurate and precise CAD/CAM restorations. Today, a patient would feel comfortable with the esthetics and fit of a CAD/CAM-generated restoration for a molar and maybe a bicuspid, but at this point some adjustment from a laboratory ceramist may be necessary so it is customized for the patient’s mouth.
“For CAD/CAM restorations for anterior teeth — though available from chairside systems — the quality of the final esthetics from machining alone is marginal at best,” McLaren said. “Ideally, anterior teeth that are initially machined, strongly benefit by skilled laboratory ceramists who can provide the finishing artistic and esthetic touches required for the esthetic zone.”
The future of CAD/CAM
As with any restoration, the success of CAD/CAM restorations are dependant on a good preparation, a detailed impression (physical or digital) and understanding how to design (or traditionally wax-up) a restoration that will satisfy dentist and patient expectations.
But CAD/CAM technology has still not advanced to the point that non-dentally trained individuals could run the technology and fabricate restorations. It will still be necessary to use a true dental professional who can visualize the finished product to make CAD/CAM work. They also need to understand the machining capabilities of the milling unit and how to optimize designs to work within those capabilities.
Sun Dental Labs’ CAD/CAM products
Suntech Full Zirconia: Using CAD/CAM technology, the anatomical features, size and shape of a Suntech Full Zirconia crown or bridge are designed from the scan of a model or from an STL file. The restoration is then milled from a single block of ceramic material in a milling chamber to a perfect replica of the digital design. The restoration is then customized with stains before being fired in a sintering oven. Then it is finished, glazed and polished to create a more natural look.
Suntech Pro Temporary Crown: Suntech Pro Temporary Crowns are designed and manufactured via CAD/CAM technologies. A tooth-colored PMMA acrylic material with a high level of breaking strength, Suntech Pro is perfect for temporary crowns, bridges and long-term temporaries.
Suntech Custom Implant Abutments: Another convenient application for CAD/CAM processes is the fabrication of customized implant abutments, either titanium or zirconia. This is the case for anterior teeth as well as bicuspids, since esthetic zone implants typically require customized abutment shapes. SunTech Implant Abutments come in titanium, zirconia and hybrid materials, are platform Independent and are available for all major implant systems.
In addition to their Suntech products, Sun Dental Labs offers e.max and Empress CAD Crowns and Copings from their CAD/CAM milling center.
(Source: Sun Dental Labs)