Experimental studies on the application of a porcelain-light-cured resin matrix system to the porcelain margin of metal-ceramic crowns.
Application of a light-cured porcelain margin is a technique which has been developed recently. In this study, we compared the porcelain margin properties of the porcelain-light-cured resin matrix system and the traditional porcelain-water system, in terms of volumetric shrinkage, density, compressive strength, surface characteristics, internal porosity, separability of the condensed porcelain from the stone die, and the marginal integrity. The experimental resin matrix was composed of BDMA or EGDMA as a base monomer, CQ as a photoinitiator, DEAEMA as a polymerization accelerator, and TEGDMA as a diluent. Compared with the conventional system, the porcelain of the resin matrix system tended to show a larger volumetric shrinkage, a smaller density and a lower compressive strength. The experimental groups containing the diluent and the traditional control group demonstrated smoother surfaces and less internal porosity than those without the diluent. The photoinitiator was thought to play an important role on the separability from the stone die and the marginal integrity; the higher the ratio of the photoinitiator (1.0 wt%), the better the separability and the fit.
Lu
Y S
YS
Department of Dentistry, Chung Shan Medical & Dental College, Taichung, Taiwan, ROC.
Yang
H W
HW
D019245:Compressive Strength; D003442:Crowns; D003776:Dental Porcelain / Q000737:chemistry*; D017267:Dental Prosthesis Design; D008027:Light; D008422:Materials Testing; D016876:Metal Ceramic Alloys; D008689:Methacrylates / Q000737:chemistry*; D011092:Polyethylene Glycols / Q000737:chemistry; D011109:Polymethacrylic Acids / Q000737:chemistry; D016062:Porosity; D018709:Statistics, Nonparametric; D013499:Surface Properties; D013729:Terpenes / Q000737:chemistry
D016876:Metal Ceramic Alloys; D008689:Methacrylates; D011109:Polymethacrylic Acids; D013729:Terpenes; D003776:Dental Porcelain; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; C048339:camphoroquinone; C004919:ethylene dimethacrylate; C102737:1,4-butanediol dimethacrylate