RESUMEN
OBJECTIVES: Activation of mineralization process in periradicular tissues following the injuries, is important in repair mechanisms. The objective of this study was to investigate the effects of CEM cement on survival and mineralization of human mesenchymal stem cells (hMSCs) and compare it with MTA. MATERIALS AND METHODS: hMSCs that were planted on test material extracts and culture media were the experimental and control groups, respectively. The cytotoxicity of these materials was investigated using Methyl thiazol tetrazolium assay. After 7 days, alizarin red staining, alkaline phosphatase (ALP) assays, and qRT-PCR were used to assess the mineralization, expression of ALP, and gene expression (collagen type 1 and osteocalcin), respectively. The results were evaluated by ANOVA analysis and multiple comparisons test. P < 0.05 was considered as statistically significant. RESULTS: Cell viability was not significantly different. Alizarin red and alkaline phosphatase staining showed mineralization in all three groups. In qRT-PCR, the expression of collagen type 1 is not significantly different among the three groups. Osteocalcin gene expression was significantly higher in the CEM group compared to the control (P < 0.05). CONCLUSION: CEM cement has acceptable toxicity and could induce mineralization process and enhance osteocalcin gene expression which is associated with mineralization in hMSCs.
RESUMEN
Objectives. To evaluate the effect of apical foramen diameter and apical barrier thickness on the sealing ability of mineral trioxide aggregate (MTA) and calcium enriched mixture (CEM) plugs in open apices. Materials and Methods. The fluid filtration method was conducted on a total of 136 roots. Samples were randomly divided into two control (n = 8) and four experimental groups (n = 30). Apical foramen diameters measuring 1.1 and 1.7 mm were shaped for groups "1 and 3" and "2 and 4", respectively. In groups 1 and 2 MTA plug and in groups 3 and 4 CEM plug was inserted. The groups were further divided into subgroups according to the thickness of the apical plugs (3- or 5-mm). Microleakage was measured at 1, 7, and 30 days. Results. Mixed ANOVA test showed that the microleakage in groups 1 and 3 as well as all 5-mm plug subgroups were significantly less than groups 2 and 4 (P < 0.05) and 3-mm subgroups (P < 0.05), respectively. Microleakage was significantly lower at 30th day (P < 0.05). Conclusions. Reducing canal diameter or increasing apical plug thickness and the time interval increases the sealing ability of apical barriers. Furthermore, in comparison to MTA, CEM plugs demonstrated superior sealing ability.