In Vitro Study On Occluding Dentinal Tubules With Nano-silver Loaded Silica System

Object:By taking advantage of nanomaterials in size and the unique pore structure of MSNs?Mesoporous silica nanoparticles?,we synthesize a novel silver-loading desensitizer.Compared with commonly used desensitizers in clinic,it,s advantages,disadvantages and characteristics were confirmed.Materials and Methods:First of all,because of the size advantage of nanomaterials and the unique pore structure of mesoporous nanosilica?MSNs?,the vertical mesoporous silica with good dispersibility and uniform particle size was prepared by biphasic delamination method.After amino-modified,the surface of MSNs was loaded with silver nanoparticles which were about 5nm diameter.The nonporous silica was synthesised with Stober method as the control switch and the surface opacity.The structure of the material was characterized by SEM,TEM,BET,FTIR,ICP and other methods.The AAS method was used to verify its ability of releasing silver ions slowly.In addition,the CCK-8 method was used to confirm the cytotoxicity of Ag-MSNs@SiO₂ at different concentrations.Secondly,the optimal concentration of blocking effect was obtained by coating different concentrations of Ag-MSNs@sSiO₂on the surface of the incised tooth slices.Four different desensitizing agents were applied to the tooth slices.According to the statistical analysis of the cross and longitudinalsectionscanningelectronmicroscopeimage,theeffectof Ag-MSNs@sSiO₂ on occluding the dentin tubles in vitro were vertified.Finally,in the silver ions solution of Ag-MSNs@sSiO₂,the changes of the hierarchical structure of bovine serum albumin?BSA?was observed by circular dichroism spectroscopy and dynamic light scattering.Results:The novel desensitizing materials had the characteristics of small size,excellent delayed-releasing properties and low cytotoxicity;The 4%material dispersion was the best concentration for occluding and there was no significant difference in occluding tubules between the it and GLUMADesensitization.;BSA showed multi-level structural changes in the material delayed-releasing solution.Conclusion:This in vitro experiment shows that the Ag-MSNs@sSiO₂ mesoporous nano-silica drug delivery system has a certain degree of sustained-release drug ability on the basis of desensitizer basic requirements.It has a guiding significance for the research of a new desensitization agent and its clinical application.