By many reports and surveys, Zirconia is now the most popular, indirect restorative material. Despite its wide use, some dentists and laboratories still have questions regarding wear, longevity, hardness, removal, esthetics, etc. We recently consulted with Rella Christensen, PhD, Director of TRAC Research Provo, UT, on zirconia properties. TRAC Research is a 37-year-old, respected dental-materials testing company that, during the past few years, has placed an emphasis on in-vitro and in-vivo zirconia restoration studies, and will publish the three-year-findings in several months. Following our conversation, we became even more convinced that full-contour zirconia is the most viable material for posterior restoration. Monolithic zirconia has it all: high-strength, low-wear, softness, low-heat conductivity, and conservative preparation.
Dr. Christensen will be joining us in Cleveland, OH on April 11, 2014 for a complete materials update seminar. This will include the release of TRAC’s findings on zirconia and emax CAD, as well as announcements of other material options that are currently being tested.
Dr. Christensen did mention a few clinical cautions. Due to the difficulty in removal and endodontic access, she recommends following preparation and occlusal reduction parameters similar to full-cast restorations. Full zirconia should be seated using reinforced glass ionomers, and not bonded. When restorations are adjusted, it is recommended a high-shine polish be completed to ensure natural wear to the opposing teeth. And, if a crown must be removed, it should be addressed with a new, fine diamond, low-to-medium pressure, with lots of water allowing the diamond to do the work.
When asked what she would place in her own mouth, the immediate response was “absolutely full-contour zirconia, and yes I’m speaking about 1st and 2nd molars”.