Osteogenic potential of rat dental pulp-derived cells on titanium surfaces

It is necessary to acquire osseointegration at an early stage in implant therapy, and a number of various approaches using titanium and cells have been evaluated. Mesenchymal cells exist in dental pulp and have been confirmed to form osseous hard tissues in vitro. However, there have been few studies on the application of dental pulp-derived stem cells in implant therapy. In this study, we cultured osteoblast-like cells derived from rat incisor pulp on titanium discs and evaluated their proliferation and differentiation potential. We further examined the possibility of applying dental pulp-derived cultured cells during titanium implant placement. Dental pulp cells were collected from the incisors of SD rats and then cultured on titanium discs. The titanium discs were treated with sulfuric acid after sandblasting with alumina. Cell proliferation and differentiation potential was evaluated by WST-1 assay, alkaline phosphatase (ALP) activity, and Alizarin red staining. Finally, the dental pulp-derived cultured cells were used in an implant test to measure the mechanical strength of the bone-titanium integration. ALP activity was significantly increased in cultured cells after 10 days compared with that after 5 days. The area of Alizarin red-positive staining increased significantly in a time-dependent manner upon incubation for 10, 20, and 30 days. The mechanical strength achieved at 2 weeks after implantation in the experimental group was significantly greater than that in the control group. These results demonstrate that osteoblast-like cells derived from rat dental pulp and cultured on surface-treated titanium discs maintained their cell differentiation potential. The results of the implant test cultured the potential application of dental pulp-derived cells to rapidly achieve osseointegration of titanium implants.