Preparation And Properties Of Dental Composite Resin Based On Persistent Luminescence Materials

Objective:Dental resin composites is widely used in the filling treatment of caries because of its simple operation,beautiful appearance and excellent mechanical properties.However,the long-term repair effect of resin composites is still affected by low monomer conversion and insufficient curing depth in resin composites.If the composite resin material itself has the ability of luminescence,the continuous curing of the composite resins can be realized,and then the conversion rate of the monomer and cured depth can be improved.Based on this consideration,in this study,the persistent luminescence materials were added into the composite resins,and its excitation wavelength and emission wavelength matched with the curing wavelength of the oral light curing units and the curing wavelength of the resin,so as to carry out continuous curing of the resin,and enhance the curing effect and curing efficiency of the composite resins.Methods:Three kinds of mature persistent luminescence materials,Ca Al₂O₄:Eu²⁺,Dy³⁺（CAED）,Sr₂Mg Si₂O₇:Eu²⁺,Dy³⁺（SMSED）and Sr₄Al₁₄O₂₅:Eu²⁺,Dy³⁺（SAED）,were doped with dental resin composites,respectively.Firstly,the crystal structure characterization and powder morphology observation of the persistent luminescence materials were carried out,and the luminescence and afterglow properties were systematically tested to verify whether the optical properties matched the wavelength required by the composite resins.Then,a series of new luminescence enhanced composite resins were prepared by doping the long-afterglow luminescence materials and composite resins with different contents respectively.The curing depth was tested.According to the experimental results of curing depth,the SMSED long-glow luminescent material doped in composite resin was selected to prepare enhanced curing modified composite resin,and Fourier transform infrared spectrometer was used to test its double bond conversion efficiency.Meanwhile,mechanical properties,water absorption solubility and cytotoxicity were tested.The comprehensive properties of SMSED reinforced curing modified composite resin were further evaluated.Results:The results show that the crystal structure and powder morphology of the long-afterglow luminescent materials were consistent with those reported in the literature.All the three materials can be excited by oral light curing lamps,and the emission wavelength coincides with the curing wavelength range of resin.Among them,SMSED shows the best excitation emission and long-afterglow performance.The results of curing depth test showed that the curing depth of all components of the resin with luminescent materials was higher than that of the control group.The three luminescent materials could stimulate camphorquinone to improve the curing of the composite resin.The increasing trend of curing depth of the three materials was first increased and then slightly decreased.Among them,the emission wavelength of SMSED was the closest to the optimal excitation wavelength of photoinitiator camphorquinone,and the enhancement curing effect was the best.The double bond conversion rate of composite resins with SMSED was improved,with no significant effect on the mechanical properties of composite resins,The water absorption properties of the materials,were reduced,while the solubility and the cytotoxicity of the materials were maintained.Conclusions:The results show that the persistent luminescence materials can improve the curing property of the composites resin and has no adverse effects on the other properties.This study provides the research basis for the application of long afterglow luminescent materials in the preparation and improvement of curing properties of reinforced solidified dental composite resin materials.Meanwhile,this material also shows potential clinical application prospects.