Effect on Pulp Cell viability and Mineralization of CaO@mesoporous-Silica

Objectives: Reparative dentin formation is one of the repair processes of pulp cell response to injury. So far, the clinical results of available pulp capping materials, such as Ca(OH)2、adhesive resin cements were not reliable. The mesoporous silica offers a unique advantage for loading and releasing large quantities of biomedical agents. The purpose of this study was to evaluate effect of novel CMS (CaO@mesoporous-Silica) on cell viability and mineralization ability of human pulp mesenchymal cell. Methods: Silica template was performed by gelatin and calcium oxalate was the source of CaO. CMS was developed by Impregnation method. Primary culture of human pulp mesenchymal cell and gingival fibroblast were seeded in 24 well plate and treated with material. MTA and Ca(OH)2 were used for comparison. Elution method was applied and the ratio of elution was 0.1mg/1ml. Cell viability was evaluated by MTT test at Day 1, 3, 7. Mineralization and differentiation was evaluated by ALP stain as well as ALP, DDP and DSP expression were assessed by PCR. The results were analyzed statistically by ANOVA with a significance level of 0.05. Tested materials were also applied on dentin disc for SEM observation. Results: ANOVA revealed that there were group differences of cell viability. The Tukey test showed that the significant difference was between Ca(OH)2 and CMS. Both of CMS and MTA had no cytotoxic effect on pulp cell. CMS significantly increased mineralization of pulp cell and induced cell differentiated into odontoblast compared to Ca(OH)2. No mineralization and differentiation were found in gingival fibroblast group. SEM showed CMS could seal dentinal tubule by recrystallization as well as Ca(OH)2 and MTA could not seal tubules. Conclusion: CaO@mesoporous-Silica is a novel material that could induce mineralization of pulp and good sealing ability. These suggest that CMS has great potential for pulp capping.