• 제목/요약/키워드: Cylindrical Surfaces

검색결과 112건 처리시간 0.016초

Silane의 처리시기와 타액오염이 도재-레진 시멘트의 전단 결합강도에 미치는 영향 (The effect of silane treatment timing and saliva contamination on shear bond strength of resin cement to porcelain)

  • 노영선;류재준;서규원
    • 대한치과보철학회지
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    • 제47권1호
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    • pp.61-69
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    • 2009
  • 서론: 인접 자연치와 아름답고 자연스런 조화를 이루는 심미적 치료를 위해 도재 수복물은 대중적인 치료방법의 하나로 잡고 있다. 임상에서 도재 수복물이 제작 후 치아에 시멘트로 접착을 하기 전 먼저 구강 내에서 시적할 때 수복물 표면에 타액, 혈액, 시적용 시멘트 등으로 인해 오염될 수 있다. 연구 목적: 이 연구의 목적은 도재 수복물로 사용되고 있는 라미네이트 도재에 실란 결합제의 처리 시기를 달리할 때와 도재 수복물을 치아에 시적 할 때 타액의 오염여부가 실란 결합제의 물리적, 화학적 반응성에 미치는 영향을 관찰하여 도재와 레진 시멘트 사이의 결합력의 안정성을 평가하는 것이다. 연구 재료 및 방법: 라미네이트용 도재를 360개의 원반모형과 5개의 정사각형 모형으로 제작하여 20군으로 나눈다. 각 군에 표면처리를 달리 한 뒤 푸리에 적외선 분광계, 접촉각 측정기와 인스트론 만능 시험기를 이용해 화학적, 물리적 비교를 하였다. 통계는 각 군의 전단 결합 강도의 유의성을 검증하기 위하여 일원분산분석(ANOVA) 후 사후검정은 던넷 다중비교 (Dunnett's multiple comparison)를 시행하였다 (P > .05). 연구 결과: 푸리에 적외선 분광 자료에 의해 본 타액 오염 및 실란의 처리 시기에 따른 화학적 변화는 크지 않았다. 접촉각은 타액 오염 후 낮아졌으나 인산으로 산 부식 후 각도가 증가하였다. 전단 결합강도값은 열 순환후의 군에서 미리 실란으로 보호한 경우에 유의한 차이가 있었다. 결론: 수복물의 내구성에 영향을 미치는 다양한 구강환경과 유사한 조건에서 수복물의 물성평가를 같이 고려해 볼 때 실란 결합제를 이용한 수복물의 접착시 실란 결합제를 수복물에 미리 도포하여 일정시간의 경과 후 수복물을 접착하며, 타액 오염이 발생할 경우 인산으로 수복물을 세척하는 것이 유용한 방법 임을 알 수 있었다

아말감의 구강내 부식 및 인공 부식에 관한 연구 (A STUDY ON IN VIVO AND IN VITRO AMALGAM CORROSION)

  • 임병목;권혁춘;엄정문
    • Restorative Dentistry and Endodontics
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    • 제22권1호
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    • pp.1-33
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    • 1997
  • The objective of this study was to analyze the in vitro and in vivo corrosion products of low and high copper amalgams. The four different types of amalgam alloy used in this study were Fine cut, Caulk spherical, Dispersalloy, and Tytin. After each amalgam alloy and Hg were triturated according to the directions of the manufacturer by means of the mechanical amalgamator(Amalgam mixer. Shinhung Co. Korea), the triturated mass was inserted into a cylindrical metal mold which was 12mm in diameter and 10mm in height. The mass was condensed by 150Kg/cm compressive force. The specimen was removed from the mold and aged at room temperature for about seven days. The standard surface preparation was routinely carried out by emery paper polishing under running water. In vitro amalgam specimens were potentiostatically polarized ten times in a normal saline solution at $37^{\circ}C$(potentiostat : HA-301. Hukuto Denko Corp. Japan). Each specimen was subjected to anodic polarization scan within the potential range -1700mV to+400mV(SCE). After corrosion tests, anodic polarization curves and corrosion potentials were obtained. The amount of component elements dissolved from amalgams into solution was measured three times by ICP AES(Inductive Coupled Plasma Atomic Emission Spectrometry: Plasma 40. Perkim Elmer Co. U.S.A.). The four different types of amalgam were filled in occlusal and buccal class I cavities of four human 3rd molars. After about five years the restorations were carefully removed after tooth extraction to preserve the structural details including the deteriorated margins. The occlusal surface, amalgam-tooth interface and the fractured surface of in vivo amalgam corrosion products were analyzed. In vivo and in vitro amalgam specimens were examined and analyzed metallographically by SEM(Scanning Electron Microscope: JSM 840. Jeol Co. Japan) and EDAX(Energy Dispersive Micro X-ray Analyser: JSM 840. Jeol Co. Japan). 1. The following results are obtained from in vitro corrosion tests. 1) Corrosion potentials of all amalgams became more noble after ten times passing through the in vitro corrosion test compared to first time. 2) After times through the test, released Cu concentration in saline solution was almost equal but highest in Fine cut. Ag and Hg ion concentration was highest in Caulk spherical and Sn was highest in Dispersalloy. 3) Analyses of surface corrosion products in vitro reveal the following results. a)The corroded surface of Caulk spherical has Na-Sn-Cl containing clusters of $5{\mu}m$ needle-like crystals and oval shapes of Sn-Cl phase, polyhedral Sn oxide phase. b)In Fine cut, there appeared to be a large Sn containing phase, surrounded by many Cu-Sn phases of $1{\mu}m$ granular shapes. c)Dispersalloy was covered by a thick reticular layer which contained Zn-Cl phase. d)In Tytin, a very thin, corroded layer had formed with irregularly growing Sn-Cl phases that looked like a stack of plates. 2. The following results are obtained by an analysis of in vivo amalgam corrosion products. 1) Occlusal surfaces of all amalgams were covered by thick amorphous layers containing Ca-P elements which were abraded by occlusal force. 2) In tooth-amalgam interface, Ca-P containing products were examined in all amalgams but were most clearly seen in low copper amalgams. 3) Sn oxide appeared as a polyhedral shape in internal space in Caulk spherical and Fine cut. 4) Apical pyramidal shaped Sn oxide and curved plate-like Sn-Cl phases resulted in Dispersalloy. 5) In Tytin, Sn oxide and Sn hydroxide were not seen but polyhedral Ag-Hg phase crystal appeared in internal space which assumed a ${\beta}_l$ phase.

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