| Poly(methyl methacrylate) has been widely used in the the fabrication of the denturebase resins for its advantages of good physical and chemical properties and easymanipulation. according to curing type, the denture base resins can be divided into threecategories: heat-polymerizing acrylic resins, auto-polymerizing acrylic resins andlight-polymerizing acrylic resins. Heat-curing denture base resin is the most popular denturebase material.After long-term exposure in the oral environment,there will be varying degrees ofcoloration and discoloration, which will affect the restoration effect. The coloration anddiscoloration of denture base resin is an indication of aging and damaged. Meanwhile，it is oneof the most common reasons for people to replace the dentures. Moreover,denture resinbases have a certain degree of water absorption and solubility in the oral environment. Somestudies have found that the coloration is related to the absorption of water molecules. Thewater molecules can be used as vectors to carry stain, therefore, water absorption andsolubility of the resin denture base will aggravate the discoloration. High water absorptionand solubility will not only affect the color stability of the material, but also have an affecton other properties of denture materials, such as dimensional stability, mechanical properties,bio-security, ultimately seriously effect the quality of resin base and the health of patient.In this study, we designed and prepared an organic-inorganic hybrid coating.The hybridsilica sol was prepared by co-hydrolysis and co-condensation of tetraethyl orthosilicate and.γ-glycidyloxypropyl trimethoxysilane. The copolymer was prepared by co-polymerization ofmethyl methacrylic acid, acrylic acid and glycidyl methacrylate. The hybrid coating withinter penetrating network structure could be formed by the formation of cross-linking of theepoxy groups on the polymer chain and silica sol. Then, the organic-inorganic hybrid coating was constructed on the surface of the denture base resins.The values of IR spectrum,hardness,adhesion and adhesion of the coating were characterized.We used four kinds of different denture base resins to produce specimens. Eachspecimen was randomly divided into experimental and control groups. We respectivelytested water absorption values, dissolution values and gloss values of the experimental andcontrol groups. Moreover, we detected the changes of color of the experimental and thecontrol groups in different colored solution for different storage time. The experimentalresults were statistically analyzed to investigate the effect of organic-inorganic hybridcoating on properties of denture base resins.Experimental results showed that the organic-inorganic hybrid coating was completelypolymerized. The hardness of the coating reached5H. The adhesion and crack resistance ofthe coating reached the highest level; The water absorption and dissolution values ofexperimental groups were significantly lower than the control groups（P<0.05）;The glossvalues of the experimental groups were significantly higher than the control group（sP<0.05）;ΔE values of85%experimental groups were significantly lower than control groups (P<0.05).In addition, in the control group, there was an interaction between the resinbrand,soaking solution and soaking time. However, in the experimental group, there wasn’tan interaction between the resin brand,soaking solution and soaking time.The results revealed that the hybrid coating has good mechanical properties. Besides,the coating could decrease the water sorption, water solubility and increase color stabilityand glossiness of the denture base resins，ultimately improve the comprehensive propertiesof the denture base resins. |
