Relevant Capability Study Of Porcelain Silane Coupling Agent

Bonding techniques today are widely used in every branches of dentistry. It has not only facilitated the clinical procedures, but also produced more conservative restorative techniques and met in some extent the growing cosmetic needs of patients. Indirect porcelain-bonded restorations are warmly welcomed by both dentists and patients. We usually use composite resin adhesive for attaching porcelain restorations to teeth or repairing the fractured porcelain of a metalloceramic restoration. Both of these applications require adequate bond strength of composite resin to the surface of porcelain.Using silane coupling agent in enhancing the bonding of composite resin to porcelain is well accepted. The silane treatment is thought to contribute to chemical bond formation between porcelain and composite resin. Concentration and additioners have significant influence on effects of silane coupling agent. Some foreign commercially available silane coupling agents have different components with functional monomer, catalyst and activator. They are vastly improved over the earlier versions.For discussing the effects of different concentrations andadditioners in porcelain silane coupling agent, testifying its effects on wetting and sealing capability, and choosing a new silane coupling agent to improve clinical procedure, we made out some new prescriptions of porcelain silane coupling agent.After pilot study, we chose 6 prescriptions for further experimental selection. Six new silane coupling agents were applied to etched or unetched porcelain surfaces respectively, Cerinate Prime was used as control. The shear bond strengths between porcelain and composite resin were determined. The effects of activators, 4 -META and concentrations of y-MPS were also discussed. Results suggested the type C silane coupling agent can generate the highest shear bond strength. Then we testified effects of silane coupling agent on wetting and sealing capability with SEM and contact angle machine. After a series study, we found that the new silane coupling agent was better than Cerinate Prime on improving bonding of composite resin to porcelain . To study the biological safety of new silane coupling agent, we also did acute toxicity test, skin irritation test and cytotoxicity test. The main findings of this study are as follows:1. 5% -MPS in porcelain silane coupling agent can generate the best effect on porcelain-composite resin bonding. Above or below this concentration may adverse.2. As an additioner in silane coupling agent, the functional monomer of 4-META can not help the bonding between porcelain and composite resin.3. Type C silane coupling agent can generate the highest shear bond strength between different porcelains and composite resin. To get the ideal bond strength in clinical procedures, we shouldcombine etching and silane treatment.4. New silane coupling agent can obviously improve the wetting of porcelain surface. There may be some relations between contactvangle on porcelain surface and bond strength of porcelain-composite resin. Improving the wetting on porcelain surface may be one of mechanisms of silane coupling agent.5. New silane coupling agent can improve the sealing capability and diminish microleakage between porcelain and composite resin. There may be some relations between sealing capability and bond strength.6. New silane coupling agent has good biological safety. In fact, it does not have acute toxicity, skin irritation and cytotoxicity from microleakage.