Gelatin/bioactive glass composite scaffold for promoting the migration and odontogenic differentiation of bone marrow mesenchymal stem cells

Recruiting periapical stem cells into the root canal and inducing their odontogenic differentiation are both vital for pulp regeneration. This study was aimed at developing a kind of bioactive composite scaffolds (G/PSC scaffolds) by combining the pH-neutral bioactive glass named PSC and gelatin. The incorporation of PSC endowed the scaffolds with bioactivity and enhanced its resistance to enzymatic hydrolysis in vitro while maintaining its high water absorption capacity. The G/PSC scaffold with a PSC content of 0.5 mg/mL in 3% gelatin solution showed the best overall performance, released large amounts of silicate ions and maintained a neutral pH after soaking in simulated body fluid (SBF). Human bone marrow mesenchymal stem cells (hBMMSCs) developed good cell morphology with affluent pseudopods on the G/PSC scaffold and infiltrated fairly deep into it. Additionally, hBMMSCs showed increased proliferation and mRNA expression levels of dentin sialophosphoprotein (DSPP), dentin matrix protein 1 (DMP-1), alkaline phosphatase (ALP), collagen type I (Col-I), osteocalcin (OCN), and runt-related transcription factor 2 (Runx2). The present results demonstrated that the G/PSC scaffold significantly promoted hBMMSC chemotaxis, proliferation and odontogenic differentiation. Therefore, the G/PSC scaffold is a promising material for pulp regeneration.