Comparative study on the fracture strength of metal-ceramic versus composite resin-veneered metal crowns in cement-retained implant-supported crowns under vertical compressive load.
- Author:
Ahran PAE
1
;
Kyung A JEON
;
Myung Rae KIM
;
Sung Hun KIM
Author Information
1. Department of Prosthodontics, Graduate School of Clinical Dentistry, Ewha Womans University, Korea.
- Publication Type:Comparative Study ; In Vitro ; Original Article
- Keywords:
Fracture strength;
Composite resin-veneered metal crowns;
Vertical compressive load
- MeSH:
Adhesives;
Axis, Cervical Vertebra;
Busan;
Crowns*;
Plastics;
Prostheses and Implants;
Stainless Steel
- From:The Journal of Korean Academy of Prosthodontics
2007;45(3):295-302
- CountryRepublic of Korea
- Language:English
-
Abstract:
STATEMENT OF PROBLEM: Fracture of the tooth-colored superstructure material is one of the main prosthetic complications in implant-supported prostheses. PURPOSE: The purpose of this in vitro study was to compare the fracture strength between the cement-retained implant-supported metal-ceramic crowns and the indirect composite resinveneered metal crowns under the vertical compressive load. MATERIAL AND METHODS: Standard implants of external type (AVANA IFR 415 Pre-mount; Osstem Co., Busan, Korea) were embedded in stainless steel blocks perpendicular to their long axis. Customized abutments were fabricated using plastic UCLA abutments (Esthetic plastic cylinder; Osstem Co., Busan, Korea). Thirty standardized copings were cast with non-precious metal (Rexillium III, Pentron, Walling ford, Conn., USA). Copings were divided into two groups of 15 specimens each (n = 15). For Group I specimens, metal-ceramic crowns were fabricated. For Group II specimens, composite resin-veneered (Sinfony, 3M-ESPE, St. Paul, MN, USA) metal crowns (Sinfony-veneered crowns) were fabricated according to manufacturer's instructions. All crowns were temporary cemented and vertically loaded with an Instron universal testing machine (Instron 3366, Instron Corp., Norwood, MA, USA). The maximum load value (N) at the moment of complete failure was recorded and all data were statistically analyzed by independent sample t-test at the significance level of 0.05. The modes of failure were also investigated with visual analysis. RESULTS: The fracture strength of Sinfony-veneered crowns (2292.7 +/- 576.0 N) was significantly greater than that of metal-ceramic crowns (1150.6 +/- 268.2 N) (P < 0.05). With regard to the failure mode, Sinfony-veneered crowns exhibited adhesive failure, while metal-ceramic crowns tended to fracture in a manner that resulted in combined failure. CONCLUSION: Sinfony-veneered crowns demonstrated a significantly higher fracture strength than that of metal-ceramic crowns in cement-retained implant-supported prostheses.
