Figure 1.
Preparation of the specimens and method of loading.
a) potential Compact Tension (CT) and beam specimens from a sectioned 3rd molar. b) flexure specimen geometry and loading configuration. The beams were arranged with the pulpal side subjected to compression. (c) CT specimen geometry and opening mode loading. By virture of the methods of sectioning and cyclic loading, fatigue crack growth occurs perpendicular to the tubules. During cyclic loading of the rectangular beams the crack generated by stress-life fatigue develops and grows in plane and parallel to the length of the tubules.