In late 2006, when Dr. Petra C. Guess arrived at NYUCD for a two-year stint as a Visiting Scholar in the Department of Biomaterials and Biomimetics from Ludwigs University College of Dentistry in Freiburg, Germany, her research on the durability of all-ceramic dental crowns had been limited to experiments with micro-thin slivers of zirconia.
Working with her mentor, Dr. Van Thompson, Professor and Chair of Biomaterials and Biomimetics, she quickly moved her research into a more advanced phase. By simultaneously utilizing all four chewing simulator machines in the NYUCD biomaterials laboratory, Dr. Guess was able to gauge the impact of variable-force chewing cycles on a range of crown sizes and shapes. This research is helping companies understand why porcelain-veneered zirconia crowns often develop cracks large enough to ruin a restoration, and how those crowns and veneers might be redesigned for greater durability.
Dr. Ricardo Zavanelli, a Visiting Scholar from Brazil in the Department of Prosthodontics is comparing Dr. Guess's findings to the results of similar durability testing on porcelain-veneered metal crowns. Dr. Zavanelli expects to test 100 crowns by the time he completes his appointment at NYUCD this summer.