전동식 니켈 티타늄 파일의 표면 결함 및 단면 형태가 반복응력 하에서 피로 파절에 미치는 영향
Effect of surface defects and cross-sectional configuration on the fatigue fracture of NiTi rotary files under cyclic loading
0
조회
0
다운로드
6
인용
0
참고문헌
초록
Abstract
The purpose of this in vitro study was to evaluate the effect of surface defects and cross-sectional configuration of NiTi rotary files on the fatigue life under cyclic loading. Three NiTi rotary files (K3TM, ProFile, and HERO 642) with #30/.04 taper were evaluated. Each rotary file was divided into 2 subgroups: control (no surface defects) and experimental group (artificial surface defects). A total of six groups of each 10 were tested. The NiTi rotary files were rotated at 300rpm using the apparatus which simulated curved canal (40 degree of curvature) until they fracture. The number of cycles to fracture was calculated and the fractured surfaces were observed with a scanning electron microscope. The data were analyzed statistically. The results showed that experimental groups with surface defects had lower number of cycles to fracture than control group but there was only a statistical significance between control and experimental group in the K3TM (p<0.05). There was no strong correlation between the cross-sectional configuration area and fracture resistance under experimental conditions. Several of fractured files demonstrated characteristic patterns of brittle fracture consistent with the propagation of pre-existing cracks. This data indicate that surface defects of NiTi rotary files may significantly decrease fatigue life and it may be one possible factor for early fracture of NiTi rotary files in clinical practice
참고문헌 (8)
- "Carnes DL. Effect to sterilization on cyclic fatigue of rotary nickel-titanium endodontic instruments. J Endod 24", 24(12), pp.843~847 (1998)
- "Cyclic fatigue testing of nickel-titanium endodontic instruments. J", 2, pp.77~85 (1997)
- "Dynamic and cyclic fatigue of engine-driven rotary nickel-titanium endodontic instruments.", 25(6), pp.434~440 (1999)
- "Influence of structure on Nickel-Titaniumendodontic instrument failure.", 27(8), pp.516~520 (2001)
- ". Fractographic analysis of experimentally separated NiTi rotary files." (2003)
- ". Cyclic fatigue of endodontic nickel-titanium rotary instruments: static and dynamic tests", 28(6), pp.448~451 (2002)
- "Impact of two theoretical cross-sections on torsional and bending stresses of nickel-titanium root canal instrument models.", 26(7), pp.414~417 (2000)
- "Smear layer production of three NiTi rotary reamers in straight root canals. A SEM study.", 96(5), pp.601~607 (2003)