A microindentation technique was employed to estimate the fracture toughness of human enamel. A pattern of increasing fracture toughness values existed from incisal to cervical in incisor enamel. Statistical analysis indicated that the molar enamel was more brittle than either the canine or incisor enamel. It was observed that the cracks emanating from the corners of an indentation propagated preferentially, with the weakest path of fracture usually extending along the cervical-incisal axis.
A microindentation technique was used to study and estimate the fracture toughness of six amalgams. A significant difference is observed between fracture toughness at the bulk and the margin of amalgams. All amalgams show significant differences in fracture toughness as a function of distance from the margin. Microindentation measurement of fracture toughness appears to be an effective method of evaluating the localized brittleness of amalgams.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.