Bioactivity of experimental scaffolds of chitosan and collagen on cultured human dental pulp cells

Abstract

Direct pulp capping (DPC) remains as a limited clinical therapy. This is because the current capping agents cause superficial coagulation necrosis after being applied on the pulpal wound. However, pulp regeneration mediated by pulp cells takes place with time. In this study, a new biomaterial (scaffold of chitosan/collagen) for DPC will be tested. It will be assessed the cytotoxicity of this specific scaffold (spongy and injectable characteristics) as well as its ability of inducing human dental pulp cells (HDPCs) to synthesize and deposit mineralized matrix. Both scaffolds will be associated to different bioactive substances (simvastatin, vitamin D3, and TGF-ß), and the following parameters will be evaluated: active cell migration (trans-wells), cell viability (Alamar Blue/Live Dead), cell migration into scaffold (light microscopic/SEM), cell differentiation (ALP activity and Real Time PCR) and mineralized matrix deposition (Alizarin Red). First of all, the cytotoxicity of the scaffolds will be evaluated on HDPCs seeded on them, and the cell viability and migration scaffolds will be analyzed. Then, the bioactive concentration of each substance capable of increasing all the cell parameters tested, will be determinate. Finally, the scaffolds plus substances will be evaluated, and all the cell parameters will be tested again. The quality of mineralized matrix will be assessed by micro-CT using a tooth slice model, on which the scaffolds will be adapted and the HDPCs seeded. Numerical data obtained will be submitted to specific statistical analysis.