Porcelain 소성 조건에 따른 지르코니아 코어와 어버트먼트 치아의 적합성 및 강도 특성

Abstract

The purposes of this study was to compare the marginal fitness and flexural strength of zirconia cores according to the firing times of porcelain. Twenty-one zirconia cores for porcelain veneered crowns and zirconia specimens were designed for experiments. The first group of cores were non veneered porcelain, the second group was veneered porcelain with firing of three times, and the third group was veneered porcelain with firing of six times. All specimens were cemented and sectioned into two planes: diagonal and labial-lingual. The measurement of the labial margin, lingual margin, and incisal margin fit was carried out using optical microscope (OM, BX60M, OLYMPUS, Japan) at 50 x. And then, the biaxial flexural strength test were performed for twenty-one zirconia specimens.

The results of this study were obtained as follows:

1. The labial marginal fit of group C (32.79 ± 16.26 ㎛) showed no significant smaller than that of two groups (P > 0.05).

2. The lingual marginal fit of group A (46.21 ± 24.04 ㎛) showed larger than that of two groups (P > 0.05). There were no significant differences between the lingual marginal gap of two groups.

3. The incisal marginal fit of group C (81.79 ± 12.84 ㎛) showed no significant smaller than that of two groups (P > 0.05).

4. The biaxial flexural strength values were identified no significant difference (P > 0.05) in all groups.