Fracture strength of the IPS empress crown : the effects of incisal reduction and axial inclination on upper canine.
- Author:
Dong Kuk SHIN
1
;
Han Joong KANG
;
Yong Suck PARK
;
Kwang Soo PARK
;
Jin Keun DONG
Author Information
1. Department of Prosthodontics, School of Dentistry, Wonkwang University, Korea.
- Publication Type:Original Article
- Keywords:
Fracture Strength;
IPS Empress Crown;
Incisal Reduction;
Axial Inclination;
Upper Canine
- MeSH:
Ceramics;
Crowns*;
Resin Cements
- From:The Journal of Korean Academy of Prosthodontics
2005;43(1):30-40
- CountryRepublic of Korea
- Language:Korean
-
Abstract:
PURPOSE: The purpose of this study was to compare the fracture strength of the IPS Empress ceramic crown according to the incisal reduction (2.0mm, 2.5mm, 3.0mm) and axial inclination (4degrees., 8.degrees, 12degrees.) of the upper canine. MATERIALS AND METHODS: After 10 metal dies were made for each group, the IPS Empress ceramic crowns were fabricated and each crown was cemented on each metal die with resin cement. The cemented crowns mounted on the testing jig were inclined 30 degrees and the universal testing machine was used to measure the fracture strength. RESULTS: 1. The fracture strength of the ceramic crown with 3.0mm depth and 12degrees inclination was the highest (839N). Crowns of 2.0mm depth and 12degrees inclination had the lowest strength (559N). 2. There was no significant difference in the fracture strength by axial inclination in the same incisal reduction group. 3. The fracture mode of the crowns was similar. Most of fracture lines began at the loading area and extended through proximal surface perpendicular to the margin irrespective of incisal reduction.
