AN EVALUATION OF DYNAMIC FATIGUE CHARACTERISTICS OF DENTAL CERAMICS FOR ALL-CERAMIC CROWN.
- Author:
Hyoung Woo YU
1
;
Tae Sung BAE
;
Kwang Yeob SONG
;
Charn Woon PARK
Author Information
1. Dept. of Prosthodontics, School of Dentistry, Chonbuk National University, Korea.
- Publication Type:Original Article
- MeSH:
Aluminum Oxide;
Ceramics*;
Crowns*;
Dental Porcelain;
Fatigue*;
Glass;
Water
- From:The Journal of Korean Academy of Prosthodontics
1997;35(4):781-792
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
This study was performed to evaluate the dynamic fatigue characteristics of the dental ceramics for all-ceramic crown. A feldspathic porcelain of VMK68, glass ceramic of IPS-Empress, and glass infiltrated alumina ceramic of In-Ceram were used. Disc specimens were prepared to the final dimensions of 12 mm in diameter and 1 mm in thickness. The biaxial flexure test was conducted using a ball-on-three-ball method. 240 specimens were tested in 37degrees C water by testing 20 samples at each of four loading rates:0.05, 0.2, 1, and 5mm/min. 60 specimens were tested in a moisture-free environment by testing 20 samples at 5mm/min. The inert strength of VMK68 was 80.25MPa, and the fatigue parameters were n=29.1, sfo=52.90MPa. The inert strength of IPS-Empress was 104.76MPa, and the fatigue parameters were n=32.46, sfo=67.52MPa. The inert strength of In-Ceram was 429.33MPa, and the fatigue parameters were n=31.46, sfo=258.36MPa. 10-year failure stresses of VMK68, IPS-Empress, and In-Ceram were 20.3MPa, 24.8MPa, and 93.6MPa, respectively. failure strength and fatigue life showed the highest value in In-Ceram, and then, IPS-Empress and VMK68.
