Investigation of Tissue-Engineered Constructs for Regenerative Endodontic Therapy.

Signature Grand, Davie, Florida, USA

Objective. The objective of this research was to conduct a histological analysis of tissue-engineered pulp constructs. Background. Stem cells from human exfoliated deciduous teeth (SHED) and periodontal stem cells (PSC) were grown to confluence and seeded on 3-dimensional tissue engineering scaffolds. Methods. The pulp tissue constructs (n=216) were created by seeding SHED or PSC on three types of scaffolds (BD Biosciences, Franklin Lakes, NJ); a synthetic open-cell D,D-L,L-polylactic acid (OPLA) scaffold, a bovine collagen scaffold (BCS), and a calcium phosphate bioceramic (CPB) scaffold. The negative control was an absence of treatment. The constructs were submerged in Dulbecco's Minimal Essential Media containing 10% fetal calf serum and antibiotics, maintained at 37 C in a 5% CO-2 atmosphere for 1-14 days. Neutral red dye (0.0016%) was added to the culture media to stain metabolically active cells. The specimens were fixed in formalin, dehydrated and processed for histology according to ISO criteria. A light microscope at x200 magnification was used to visualize cells within the dental pulp constructs. Data was analyzed by Chi-square statistical tests (p values) at a significance of 95%. Results. SHED and PSC survival was optimal in the OPLA and BCS pulp constructs, but not the CPB pulp constructs (p < 0.05) especially over longer time periods (p < 0.05). Conclusion. These in vitro results suggest that the OPLA or BCS tissue-engineered pulp constructs have the potential to be used as part of future regenerative endodontic therapy. Grants. This study was supported by the AAEF and NSU.