A Study Of Metal-ceramic Bonding On A New Type Of Cobalt-chromium Alloy For Both Dental Framework And Porcelain Fused To Metal

With the development of prosthonditics, a new technique which combines PFM technique and casting framework of RPD appears and has being applied by more and more dentists. So we developed a new type of Co-Cr dental alloy which has good metal-porcelain matching and could be cast for RPD framework. The fomer research showed that it had good biological compatibility and mechnical capability for clinical use. But how to improve the bonding strength of the porcelain bonded to alloy becomes the key point of our research in order to get better restorative effect. Thus we used five different surface treatment technologies to the aolly, and discussed their effects on metal-porcelain bonding strength. In the same time the interface between metal and porcelain was observed and analyzed by SEM and EPMA. The conclusions were drawed as followings:(1)Before applied for porcelain, the aolly should be oxidated for 5 minutes at the temperature of 980℃.(2)Using the Sol-Gel technique could improve the bonding of the porcelain to our alloy.(3)Before applied for porcelain, the metal substrate surface was smearedwith nano-scale material (nano-SiO₂, nano-gold particles), and the nano-scale material had a positive effect to increase the bonding strength.(4)Two methods of vacuum coating film were used in our study in order to increase the bonding strength , one was magnetron reactive sputter deposition, and the other was electron beam vapour deposition. The former had a positive effect while the latter had a negative effect.(5)The plasma spraying technology had a significative function in enhancing the bonding strength.