OBJECTIVE: Comparison of physical and mechanical properties of one conventional and a new NiTi wire, which had received an additional thermomechanical treatment. METHODS: Specimens of both conventional (NiTi) and the new type of wire, called M-Wire (MW), were subjected to tensile and three-point bending tests, Vickers microhardness measurements, and to rotating-bending fatigue tests at a strain-controlled level of 6%. Fracture surfaces were observed by scanning electron microscopy and the non-deformed microstructures by transmission electron microscopy. RESULTS: The thermomechanical treatment applied to produce the M-Wire apparently increased the tensile strength and Vickers microhardness of the material, but its apparent Young modulus was smaller than that of conventionally treated NiTi. The three-point bending tests showed a higher flexibility for MW which also exhibited a significantly higher number of cycles to failure. SIGNIFICANCE: M-Wire presented mechanical properties that can render endodontic instruments more flexible and fatigue resistant than those made with conventionally processed NiTi wires.
OBJECTIVE: Comparison of physical and mechanical properties of one conventional and a new NiTi wire, which had received an additional thermomechanical treatment. METHODS: Specimens of both conventional (NiTi) and the new type of wire, called M-Wire (MW), were subjected to tensile and three-point bending tests, Vickers microhardness measurements, and to rotating-bending fatigue tests at a strain-controlled level of 6%. Fracture surfaces were observed by scanning electron microscopy and the non-deformed microstructures by transmission electron microscopy. RESULTS: The thermomechanical treatment applied to produce the M-Wire apparently increased the tensile strength and Vickers microhardness of the material, but its apparent Young modulus was smaller than that of conventionally treated NiTi. The three-point bending tests showed a higher flexibility for MW which also exhibited a significantly higher number of cycles to failure. SIGNIFICANCE: M-Wire presented mechanical properties that can render endodontic instruments more flexible and fatigue resistant than those made with conventionally processed NiTi wires.
Authors: Suzanny C S Martins; Jessica D Silva; Paula R Garcia; Ana C D Viana; Vicente T L Buono; Leandro A Santos Journal: Clin Oral Investig Date: 2022-01-17 Impact factor: 3.573
Authors: Felipe Augusto Restrepo-Restrepo; Viviana Andrea Holguín-Vásquez; Syldana Julieth Cañas-Jiménez; Paula Andrea Villa-Machado; Sara Ochoa-Soto; Claudia Patricia Ossa-Orozco; Sergio Iván Tobón-Arroyave Journal: Dent Res J (Isfahan) Date: 2021-06-22