title: Materials design of ceramic-based layer structures for crowns.
abstract: Radial cracking has been identified as the primary mode of failure in all-ceramic crowns. This study investigates the hypothesis that critical loads for radial cracking in crown-like layers vary explicitly as the square of ceramic layer thickness. Experimental data from tests with spherical indenters on model flat laminates of selected dental ceramics bonded to clear polycarbonate bases (simulating crown/dentin structures) are presented. Damage initiation events are video-recorded in situ during applied loading, and critical loads are measured. The results demonstrate an increase in the resistance to radial cracking for zirconia relative to alumina and for alumina relative to porcelain. The study provides simple a priori predictions of failure in prospective ceramic/substrate bilayers and ranks ceramic materials for best clinical performance.
authors.affiliation: Materials Science and Engineering Laboratory, National Institute of Standards and Technology, Gaithersburg, MD 20899-8500, USA. brian.lawn@nist.gov
authors.forename: B R
authors.initials: BR
authors.lastname: Lawn
authors.forename: Y
authors.initials: Y
authors.lastname: Deng
authors.forename: I K
authors.initials: IK
authors.lastname: Lloyd
authors.forename: M N
authors.initials: MN
authors.lastname: Janal
authors.forename: E D
authors.initials: ED
authors.lastname: Rekow
authors.forename: V P
authors.initials: VP
authors.lastname: Thompson
mesh_terms: D000537:Aluminum Oxide; D002516:Ceramics; D003187:Compliance; D003442:Crowns; D003776:Dental Porcelain; D019232:Dental Restoration Failure; D003799:Dental Stress Analysis; D003801:Dental Veneers; D003804:Dentin; D004548:Elasticity; D006244:Hardness; D006801:Humans; D016014:Linear Models; D008422:Materials Testing; D018583:Pliability; D015040:Zirconium
chemical_list: D003776:Dental Porcelain; C023506:Glass ceramics; D015040:Zirconium; D000537:Aluminum Oxide; C028541:zirconium oxide