Earticle

초록

영어

The goal of esthetic restoration is to achieve morphologic, optical, and biologic acceptance. Creation of a natural looking ceramic restoration, which blends harmoniously with surrounding dentition, is not always achieved.
A successful color match is an important aspect of any esthetic dental restoration. Since natural enamel has inherent translucency, it is important that ceramic restorations reproduce the translucency and color of the natural teeth. However, the final color match of porcelain crowns to adjacent natural dentition remains some problem.
Difficulties related to color matching arise from the structural differences that exist between metal ceramic crowns and natural teeth, the limited range of available ceramic shades, inadequate shade guides, different types of metal alloys, repeated firing, the condensation technique, and varying compositions of ceramic materials. Many factors contribute to the esthetic success of dental restoration: optical properties such as color and its elements of hue, value, and chroma; translucency and opacity; light transmission and scattering; and metamerism and fluorescence.
The purpose of this study was to determine the color changes of metal-ceramic system with different veneering porcelain powder after repeated firing.
The objectives of this in vitro study were to measure the lightness(L*), chromaticity(a*), chromaticity(b*), chroma(C*), hue(h), reflectance(%), color difference( E).
The following conclusions were obtained:
1. An increase in the number of firings resulted in decrease in lightness(L*) but increase in chromacticity(a*) with all porcelain. After the second sintering resulted in decrease in chromacticity(b*) with opaque-dentin porcelain and dentin porcelain but in increase with enamel porcelain and translucency porcelain. And after the second sintering resulted in decrease in chroma(C*) with opaque-dentin porcelain and dentin porcelain, but on the whole side in decrease with enamel porcelain and translucency porcelain.
2. After the second firing, a increase in the number of firings resulted in decrease reflectance(%) in all wavelength.
3. There were noticeable color differences( E) between first sintering and multiple firings(dentin porcelain: 5.29 ~ 8.15, opaque-dentin porcelain: 4.83~8.2, enamel porcelain: 8.93~13.15, translucency porcelain: 9.37~12.91), but the color difference( E) after second sintering were down to 4.87 in all porcelain.
4. Given the NBS Criteria, a ‘'trace’' was not found this study but a ‘'slight’' was found 2-3, 3-5 in dentin porcelain, 2-3 in opaque-dentin porcelain, 3-5, 5-10 in enamel porcelain and translucency porcelain, a ‘'noticeable’' was 2-5, 3-10, 5-10 in dentin porcelain and opaque-dentin porcelain, 2-3, 2-5, 3-10 in enamel porcelain 2-3, 3-10 in translucency porcelain, an ‘'appreciable’' was 1-2, 1-3, 2-10 in dentin porcelain 1-2, 1-3, 2-10, 3-10 in opaquedentin porcelain, 2-10 in enamel porcelain, 2-5, 2-10 in ranslucency porcelain, a ‘'much’' was 1-5, 1-10 in dentin porcelain and opaque-dentin porcelain, 1-2, 1-3, 1-5 in enamel porcelain 1-2, 1-3, 1-5, 1-10 in translucency porcelain, a ‘'very much’' was 1-10 in enamel porcelain.

목차

[Abstract]
 Ⅰ. 서론
 Ⅱ. 연구방법
  1. 실험재료
  2. 실험방법
 Ⅲ. 연구결과
  1. 명도변화(L*)
  2. 색도변화(red-green cxis, a*)
  3. 색도변화(yellow-blue cxis, b*)
  4. 채도변화(C*)
  5. 색상변화(h)
  6. 반사율(%)
  7. 도재의 특성에 따른 변화
  8. 색차(ΔE)
  9. NBS(National Bureau Standards) unit
 Ⅳ. 고찰
 Ⅴ. 결론
 참고문헌

키워드

저자

• 황재선 [ Jae-Sun Hwang | 동남보건대학 치기공과 ]

참고문헌

발행기관

간행물

표지보기 관심저널 등록

• 간행물명

  대한치과기공학회지 [THE JOURNAL OF KOREAN ACADEMY OF DENTAL TECHNOLOGY]

• 간기

  계간

• pISSN

  1229-3954

• eISSN

  2288-5218

• 수록기간

  1979~2026

• 등재여부

  KCI 등재

• 십진분류

  KDC 515 DDC 617