Adaptability of zirconia core fabricated by cold isostatic pressing.
10.4047/jkap.2010.48.2.143
- Author:
Yoon Jeong SEO
1
;
Kwi Dug YUN
;
Hyun Seung KIM
;
Sang Won PARK
Author Information
1. Department of Prosthodontics, School of Dentistry, Chonnam National University, Gwangju, Korea. psw320@chonnam.ac.kr
- Publication Type:Original Article
- Keywords:
Core;
Cold isostatic pressing;
Marginal fit;
Shrinkage;
Zirconia
- MeSH:
Cold Temperature;
Crowns;
Dental Porcelain;
Ethylnitrosourea;
Zirconium
- From:The Journal of Korean Academy of Prosthodontics
2010;48(2):143-150
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: The purpose of this study is to fabricate the new zirconia block (CNU block) and to evaluate fit of core and porcelain veneered zirconia crown. MATERIAL AND METHODS: The experimental blocks were fabricated from the commercial ytrria-stabilized zirconia powder (KZ-3YE Type A). The powder was uniaxial pressing and the green bodies were conducted using the Cold Isostatic Pressing. The zirconia blocks were presintered at 1040degrees C and the final sintering was performed at 1450degrees C. The Kavo Everest ZS blank(R) (KaVo, Biberach/Ri beta.) was used as a control group. The linear shrinkage of CNU block and Kavo block were compared. Twenty-one cores for porcelain veneered crowns were fabricated with CAD/CAM system (Everest(R), Biberach/Ribeta.). Group I: seven cores fabricated from Kavo blocks, Group II: seven cores fabricated from CNU blocks, Group III: seven cores from CNU blocks and porcelain veneering for crowns. All specimens were cemented and sectioned into two planes: diagonal and bucco-lingual. The measurement of the marginal, internal, and occlusal fit was carried out using SEM (S-4800(R)) at 30 x. The results were analyzed by one-way ANOVA test. RESULTS: The linear shrinkage of the CNU block and the KaVo block was 19.00% and 20.09%. The marginal gap of cores (29.67 +/- 6.58 micrometer) fabricated from CNU blocks showed significantly smaller than that of the cores of Kavo blocks (36.84 +/- 7.18 micrometer) (P < .05). The internal gaps of the porcelain veneered crowns (32.23 +/- 6.33 micrometer) were larger than those of the other two groups (37.57 +/- 6.81 micrometer and 38.14 +/- 6.81 micrometer). CONCLUSION: No statistically significant difference was found in between experimental groups and control group. The experimental groups in marginal gap showed significantly smaller than the control group.
