Affiliation: | a Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore, MD, USA;b Paffenbarger Research Center, American Dental Association Foundation, National Institute of Standards and Technology, Gaithersburg, MD, USA;c Department of Materials, ETH Zurich, Zurich, Switzerland;d Department of Endodontics, Prosthodontics, and Operative Dentistry, Baltimore College of Dental Surgery, University of Maryland, Baltimore, MD, USA |