The use of dental papillae cells and millipore filter for bioengineered dentin

Objective To observe the ability of SD rat dental papillae cells forming dentin-like structure induced by millipore filter combined with transforming growth factor-β1 (TGF-β1). Methods The first passage SD rat dental papillae cells were enzymatically dissociated and centrifuged to obtain a cell mass.The cell mass was seeded on the millipore filter combined with TGF-β1. The complex was incubated for 6 d in vitro or transplanted under the renal capsule for 2 weeks. Then the differentiation of dental papillae cells on the filter and the formation of mineral tissue on the implant were analyzed. Results A layer of polarized columnar cells were observed along the surface of the millipore filter, with cell processes extending into the porous media. Dentin sialoprotein(DSP) and dentin matrix protein-1 ( DMP-1 ) were positive in these cells.After 2 weeks, tubular dentin matrix was deposited on the surface of the aligned cells. Scanning electron microscopy showed that the thickness of newly formed tubular dentin was consistent. DSP and DMP-1 were expressed in columnar cells, tubular matrix and the dental papillae cells adjacent to the filter. Conclusions The millipore filter combined with TGF-β1 could effectively recruit progenitors onto its surface and induce odontoblast differentiation, secrete matrix in a homogenous manner, leading to dentinogenesis. Key words: Dental papilla;  Micropore filters;  Cell differentiation;  Dentin regeneration