Same-Day Restorations With Biomimetic Dentistry
GC America Inc’s GC Initial® LiSi Blocks and G-CEM ONE™ provide esthetics and durability
Yao-Lin Tang, DDS
Yao-Lin Tang, DDS, was an early adopter of chairside milling, and he is still going strong with it today. Single-visit restorations are a key offering at Pacific Dental Center, Tang's private practice in San Mateo, California. "With CAD/CAM single-visit dentistry," Tang says, "I can save the patient time, and I can maintain control of the end result instead of sending the case to a laboratory and letting them control my margin morphology and contacts. This way, I can prepare the teeth while knowing where the margin is and controlling it. If necessary, I have the opportunity to go back and make corrections and improvements. This allows me to provide the best possible dentistry to my patients."
Although single-visit restorations may not be new in the profession, Tang notes that they still impress patients. "Patients are wowed," he says. "They tell me that they did not know single-visit restorations were possible, and some patients even record videos of the process on their phones. As a result, I get a lot of referrals from patients who tell friends and family about their single-visit experiences."
Tang stays up to date on the latest milling technology and developments as a CDOCS visiting faculty member. He travels around the world teaching and, in the process, brings back knowledge to his own office. "The software, hardware, and materials all continue to improve," he says, "so staying on top of these developments and taking advantage of them requires continued learning. I travel to teach but also to learn."
Approximately 5 years ago, Tang's travels led him to a lecture by Pascal Magne, DMD, MSc, PhD. He was inspired by Magne's philosophy of biomimetic dentistry and decided to adopt it within his own practice. "With biomimetic dentistry, we try to imitate natural tooth structure," Tang says.
For his in-office milled restorations, imitating natural dentition meant finding something esthetic with similar properties to enamel, and Tang settled on GC Initial® LiSi Block from GC America Inc. "GC Initial LiSi Block checks all the boxes for biomimetic dentistry," he says. "It has very similar strength, elastic modulus, and hardness when compared with enamel. Furthermore, lithium disilicate is bondable, which is ideal for biomimetic dentistry."
GC Initial LiSi Block features GC's proprietary High Density Micronization (HDM) technology for CAD/CAM dentistry to deliver high wear resistance, smooth margins, and esthetic final results. The unique, ultrafine crystal makes it easy to grind, and it can be quickly milled in its fully crystallized stage. High gloss and natural opalescence can be obtained in a few minutes through polishing only, and then the restoration is ready for luting; the esthetics of the restoration will be maintained over time. The blocks are available in four esthetic shades and two translucencies. When more characterization is required, the GC Initial® ceramic line comprises fully synergistic esthetic solutions.
According to Tang, the fully crystallized nature of GC Initial LiSi Block differentiates the material from other lithium disilicates. "Lithium disilicate has been available for more than a decade, and it has proven to be very reliable with good long-term results," he says. "The problem with pre-crystallized blocks is that they required an oven, and stain and glaze must be applied when the material is still in the purple state. Also, the margins chip more easily. So many things can happen in the oven. The advantage of GC Initial LiSi Block is that what you see is what you get. It is already crystallized, so you do not need an oven. If the restorations do not need to be characterized, you can simply mill, polish, and cement. Even if you decide to characterize, because it is already in the final stage, whatever amount of stain and glaze you put on the restoration is the amount that will show in the final result." Crystallizing in an oven also shrinks materials, so avoiding that factor helps Tang maintain more control over the final restoration. "Shrinkage during the crystallization process creates a marginal gap," he says. "That is a primary reason why GC Initial LiSi Block has the best fitting margins." Biomimetic dentistry also involves being minimally invasive, and Tang says he can mill GC Initial LiSi Block at 0.3 mm to 0.5 mm. "When we do veneer cases with this material," he says, "we prepare very minimally. These blocks can be milled thinner than others because they do not need to go into the oven."
The bonding component of biomimetic dentistry is critical as well, and Tang uses GC America Inc's G-CEM ONE™—a self-adhesive dual-cure resin cement that brings together high bond strength, effortless cleanup, and long-lasting esthetics as well as an excellent self-curing ability for a wide range of indications in one product solution. G-CEM ONE is effective in all cementation procedures for any type of restoration, from metal-based to resin and all-ceramic inlays, onlays, crowns, bridges, and posts. "GC Initial LiSi Block simulates enamel, but you need to be able to bond, and G-CEM ONE is very versatile in its ability to do that," Tang says. "You can etch with it if you want, but it is not necessary. The dual-cure capability makes it possible to use G-CEM ONE on all types of restorations, even under low-translucency or opaque materials such as metal or opaque zirconia." The optional Adhesive Enhancing Primer (AEP) and its innovative GC Touch Cure feature provide optimal bond strength in challenging clinical situations, such as low-retentive surfaces. "The ability to etch and add AEP to increase bond strength is a nice option," Tang says. "The cement also is very easy to use and easy to clean up."
As versatile, esthetic, and durable as GC Initial LiSi Block and G-CEM ONE are, their reliability is just as important. "GC is a very conservative company, and the product specifications that they provide are always conservative," Tang says. "I am very confident using these materials. If the catalog says GC Initial LiSi Block has 400 MPa of strength, I am certain that it has at least that much." With that confidence, Tang is able to provide his patients with efficiency, minimal invasiveness, and high quality. "Everything goes back to providing the best possible dentistry to the patient," he says.
• GC Initial LiSi Block reduces chair time-just mill, polish, and place.
• GC Initial LiSi Block provides durable esthetics and smooth margins as well as natural opalescence.
• G-CEM ONE is universal, with excellent bond strength to enamel, dentin, and all indirect materials.
• G-CEM ONE provides optimal bond strength for retentive and non-retentive preparations thanks to the optional AEP.