Community Magazine September 2011

76 COmmuNItY mAGAZINe JaCQueS DOueCK, DDS ZIRCONIUM : Dentistry’s Amazing Metal-Free Crowns Gold has always been the strongest most durable material for dental crowns (caps), and it still is. But patients are asking, “With today’s technology, isn’t there a tooth- colored crown that is unbreakable?” Until recently, the answer was always “no.” But once zirconium arrived on the scene, everything changed. Besides being the strongest metal-free crown, zirconium offers excellent long-term stability with no allergenic risks. Gold crowns (left) are strong, but the BruxZir replacement is far more natural looking. Lava crowns are attractive enough for front teeth and yet very durable. The Strongest BruxZir™ Solid Zirconia is a full-contour solid zirconia crown or bridge with no porcelain overlay. More brawn than beauty, BruxZir is a great alternative to full metal crowns on back molars. Virtually chip-proof, these crowns and bridges are the ideal restoration for bruxers and grinders, implant crowns and areas with a tight bite. Designed and milled using computer aided design and modeling (CAD/CAM) , BruxZir is heated for 6-10 hours at 1,530 degrees Celsius. The final crown or bridge emerges nearly “bulletproof” and is glazed to a smooth surface. BruxZir Solid Zirconia crowns and bridges are backed by a seven-year replacement warranty . Is Gold Obsolete? Even at over $1,800 an ounce, gold crowns are still necessary at times, depending on the bite, size and shape of the remaining tooth and esthetic demands of the area. Because gold is malleable and softer than zirconium, it may be gentler on the bite. In some cases, we would rather the gold wear out than damage the jaw joint. We usually reserve gold for the last molars in the mouth where they are hidden and the forces are much greater. But whereas gold was once the only real long-lasting option for crowns, thanks to zirconium, patients can now opt for a durable, non-allergenic and attractive crown that looks much like their natural teeth. Strength and Beauty Lava™ crowns combine the esthetics our patients demand with the strength they need. Lab tests have shown that the fracture toughness and flexural strength of Lava crowns are significantly higher than any other all- ceramic restorations. There is no metal to show through the ceramic, and no unsightly black lines at the edges. This esthetic restoration is built on a foundation of the same zirconium used in the BruxZir crowns using CAD/CAM technology, which gives the final restoration a superb fit, and porcelain, which gives beautiful, translucent opalescence. After heating the foundation for ten hours to establish strength and fracture resistance, the framework is layered with the most esthetically pleasing porcelain material. The final restoration demonstrates exceptional marginal fit, tooth-like translucency and long- term durability. These crowns and bridges are touted as one of themost attractive and clinically proven all-ceramic restorations available today.