It depends on the nature of the biomaterials you are trying to employ for you endodontic experiment. I think NiTi wires are predominantly employed for such purposes. You can check the SN curve for different NiTi wires at different temperatures.
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D. Arola and R. K. Reprogel, "Effects of aging on the mechanical behavior of human dentin," Biomaterials, 26[18] 4051-61 (2005).
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