Cartilage tissue engineering is a promising treatment for damaged or diseased cartilage that requires thorough understanding of influential parameters involved in chondrogenic differentiation. This study examined how 4-h application of cyclic hydrostatic pressure (CHP) of 5 MPa at 0.5 Hz could modulate chondroinduction of human adipose-derived mesenchymal stem cells (hAMSCs) in vitro. Four groups were examined including a negative control group, a chemical group treated by growth factor for 10 days, a mechanical group exposed to 4-h loading on the 10th day of pellet culture without any chondrogenic stimulator, and finally a chemical-mechanical group subjected to both growth factor and loading. Application of cyclic hydrostatic pressure increased the expression of chondrogenic genes, including sox9 and aggrecan to higher levels than those of the chemical group. This study indicates that cyclic hydrostatic pressure initiates and enhances the chondrogenic differentiation of mesenchymal stem cells with or without growth factors in vitro and confirms the important role of hydrostatic pressure during chondrogenesis in vivo.

Objectives: Various studies have identified green tea and Aloe vera as a suitable medium for avulsed teeth. The aim of this study was to evaluate and compare the viability of periodontal ligament (PDL) fibroblasts following treatment with the extracts of these two plants and their mixture. Materials and Methods: Human PDL fibroblasts were purchased and treated with different concentrations of Aloe vera, green tea, and a combination of these two extracts. Hank’s balanced salt solution and culture medium were employed as positive and negative controls, respectively. Viability was assessed using the MTT assay. Two-way ANOVA and post-hoc tests were used for statistical analysis (P<0.05). Results: There was a significant difference in PDL fibroblast viability between different concentrations of the extracts. Higher concentrations of green tea and the combination of the two extracts significantly increased cell viability. Higher concentrations of Aloe vera had the least positive effect on maintaining the viability of these cells. Conclusion: If confirmed by further studies, the combination of Aloe vera and green tea extracts might be considered as a suitable media for different purposes like storing avulsed teeth.