Evaluation of Novel Degradable Poly-Bioceramc Scaffolds of PDLIA/Toothapatite/TCP using Human Dental Pulp Stem Cells for Tooth Bioengineering

Abstract

In this study two types of scaffolds which have taken the merits of polymer and bioceramics were prepared, and in vitro and in vivo effects of the novel degradable polymer-bioceramic scaffolds seeded with human dental pulp stem cells (hDPSCs) were investigated. Three elements were considered for the scaffolds; poly-DL-lactide (PDLLA), as degradable polymer, and tooth apatite (TA) and beta-tricalciumphosphate (TCP) as degradable bioceramics. The first scaffold consists of PDLLA exclusively, the second of PDLLA and TA (I:1) and the third of PDLLA, TA and TCP (1:1:1). The scaffolds were compared with each other in vitro and in vivo using hDPSCs as their cell source. hDPSCs were isolated from extracted third molars, cultured, attached, proliferated and differentiated prior to the in vitro and in vivo experiments. Scanning electron microscope observation was carried out to reveal the attachment and growth of hDPSCs on the surfaces of three scaffolds, and the quantitative assay of cell proliferation was also detected. It was shown that hDPSCs attached and spread further in the polymer-bioceramic groups (PDLLA/TA/TCP and PDLLA/TA) compared to the polymer group (PDLLA), and there was also less inflammatory reaction in the polymer-bioceramic scaffolds, transplanted subcutaneously in the dorsal area of immunocompromised mice. In addition, the polymer-bioceramic groups (PDLLA/TA/TCP, PDLLA/TA) showed intensive cementum-like mineralization in vivo. Thus, it could be concluded that the polymer-bioceramic groups might serve as novel potential scaffolds for tooth bioengineering.