title: R-curve behavior of dental ceramic materials.
abstract: Some technical ceramics exhibit the R-curve effect, i.e., an increasing fracture resistance with crack extension which is a desirable material property because more energy is necessary to propagate a microscopic crack. The objective of this study was to prove whether dental ceramic materials exhibit R-curve behavior. Nine dental ceramics were examined by the indentation-strength method. It was found that all of the tested ceramic materials exhibit a rising R-curve with crack extension. The R-curve behavior was more pronounced for the high-strength materials In-Ceram Alumina, monolithic alumina, and especially Empress 2. We conclude from our results that the mechanical behavior of a dental ceramic material can be judged more comprehensively, if the R-curve of the respective material is known.
authors.affiliation: Department of Dental Prosthetics, Section of Dental Materials, University of Technology Aachen, Pauwelsstrasse 30, D-52074 Aachen, Germany. h.fischer@rwth-aachen.de
authors.forename: H
authors.initials: H
authors.lastname: Fischer
authors.forename: W
authors.initials: W
authors.lastname: Rentzsch
authors.forename: R
authors.initials: R
authors.lastname: Marx
mesh_terms: D000465:Algorithms; D000537:Aluminum Oxide / Q000737:chemistry; D000538:Aluminum Silicates / Q000737:chemistry; D002516:Ceramics / Q000737:chemistry*; D003764:Dental Materials / Q000737:chemistry*; D003776:Dental Porcelain / Q000737:chemistry; D006244:Hardness; D006801:Humans; D016018:Least-Squares Analysis; D016014:Linear Models; D008422:Materials Testing; D018583:Pliability; D013314:Stress, Mechanical; D013499:Surface Properties
chemical_list: D000538:Aluminum Silicates; D003764:Dental Materials; C095718:Duceram; C075815:IPS-Empress ceramic; C111324:vitadur alpha omega; D003776:Dental Porcelain; C074543:Cerec; C070870:In-Ceram; C032328:Frialit; D000537:Aluminum Oxide