Publications
Detailed Information
The Effect of Surface Defects on the Cyclic Fatigue Fracture of HEROShaper Ni-Ti rotary files in a Dynamic Model : A Fractographic Analysis : Fractographic 분석을 통한 HEROShaper 니켈티타늄 전동 파일의 피로파절에 미치는 표면결함의 역할
DC Field | Value | Language |
---|---|---|
dc.contributor.author | Lee, Jung-Kyu | - |
dc.contributor.author | Kim, Eui-Sung | - |
dc.contributor.author | Kang, Myoung-Whai | - |
dc.contributor.author | Kum, Kee-Yeon | - |
dc.date.accessioned | 2011-10-18T06:18:21Z | - |
dc.date.available | 2011-10-18T06:18:21Z | - |
dc.date.issued | 2007 | - |
dc.identifier.citation | 대한치과보존학회지 2007;32:130-137 | en |
dc.identifier.issn | 1225-0864 | - |
dc.identifier.uri | https://hdl.handle.net/10371/74280 | - |
dc.description.abstract | This in vitro study examined the effect of surface defects on cutting blades on the extent of the cyclic fatigue fracture of HEROShaper Ni-Ti rotary files using fractographic analysis of the fractured surfaces. A total of 45 HEROShaper (MicroMega) Ni-Ti rotary flies with a #30/.04 taper were divided into three groups of 15 each. Group 1 contained new HEROShapers without any surface defects. Group 2 contained HEROShapers with manufacturing defects such as metal rollover and machining marks. Croup 3 contained HEROShapers that had been clinically used for the canal preparation of 4-6 molars A fatigue-testing device was designed to allow cyclic tension and compressive stress on the tip of the instrument whilst maintaining similar conditions to those experienced in a clinic. The level of fatigue fracture time was measured using a computer connected the system. Statistical analysis was performed using a Tukey's test. Scanning electron microscopy (SEM) was used for fractographic analysis of the fractured surfaces. The fatigue fracture time between groups 1 and 2, and between groups 1 and 3 was significantly different (p<0.05) but there was no significant difference between groups 2 and 3 (p>0.05). A low magnification SEM views show brittle fracture as the main initial failure mode At higher magnification, the brittle fracture region showed clusters of fatigue striations and a large number of secondary cracks. These fractures typically led to a central region of catastrophic ductile failure. Qualitatively, the ductile fracture region was characterized by the formation of microvoids and dimpling. The fractured surfaces of the HEROShapers in groups 2 and 3 were always associated with pre-existing surface defects.본 연구의 목적은 니켈티타늄 전동파일의 피로파절에 있어서 표면 결함의 역할을 규명하고자 fatigue tester에서 반복적 인 fatigue force를 부여한 후 파절된 단면을 주사전자현미 경으로 관찰하여 파절 역학을 규명하는 것이다. 총 45개의 #30/.04 taper와 21 mm의 HEROShaper 니켈-티타늄 전동파일을 15개씩 3개의 군으로 분류하였다. 제 1군은 결함이 없는 새 HEROShaper파일, 제 2군은 제조과정에서 metal rollover나 machining marks와 같은 표면결함을 갖는 HEROShaper파일, 제 3군은 임상에서 4- 6개의 구치부 근관의 확대에 사용한 HEROShaper 파일을 사용하였다. 모든 파일들은 회전속도(300 rpm)와 pecking distance (3 mm)가 일정하게 맞춘 fatigue tester에서 파절될 때까지 시간을 측정한 후 통계분석을 통해 각 군간의 유의성을 분석하였고, 파절 단면의 farctographic analysis를 통해 파절역학을 규명하고자 하였다 실험결과 평균 파절시간에 있어서 group 1과 2, group 1과 3사이에는 통계학적으로 유의할 만한 차이가 있었으나 (p<0.05), group 2와 3사이에는 통계학적인 차이가 없었다. Fractographic analysis 결과 대부분의 파절면에서 microvoid와 dimple 소견을 갖는 ductile fracture양상이 관찰되었다. 또한 brittle fracture가 일어난 파절면에서는 파절선 전방에 수 많은 striation들이 관찰되었고 transgranular 및 intergranular cleavage 소견도 보였다. 표면결함이 있는 제 2, 3 군의 파절단면에서는 모든 시편에서 표면결함이 관찰되었다. | en |
dc.language.iso | en | en |
dc.publisher | 대한치과보존학회 | en |
dc.subject | Surface defect | en |
dc.subject | Fatigue fracture | en |
dc.subject | Ductile fracture | en |
dc.subject | Striation | en |
dc.subject | HEROShaper | en |
dc.subject | Fractographic analysis | en |
dc.subject | 표면결함 | en |
dc.subject | 피로파절 | en |
dc.subject | 연성파절 | en |
dc.subject | 파절시간 | en |
dc.title | The Effect of Surface Defects on the Cyclic Fatigue Fracture of HEROShaper Ni-Ti rotary files in a Dynamic Model : A Fractographic Analysis | en |
dc.title.alternative | Fractographic 분석을 통한 HEROShaper 니켈티타늄 전동 파일의 피로파절에 미치는 표면결함의 역할 | en |
dc.type | Article | en |
dc.contributor.AlternativeAuthor | 이정규 | - |
dc.contributor.AlternativeAuthor | 김의성 | - |
dc.contributor.AlternativeAuthor | 강명회 | - |
dc.contributor.AlternativeAuthor | 금기연 | - |
- Appears in Collections:
- Files in This Item:
Item View & Download Count
Items in S-Space are protected by copyright, with all rights reserved, unless otherwise indicated.