Tissue Engineered Dental-Pulp Implanted within Endodontically Treated Teeth

Objectives: The objective of this research was conduct an ultrastructural scanning electron microscope investigation of tissue engineered dental pulp constructs implanted within endodontically-treated teeth. Methods: Stem cells from human exfoliated deciduous teeth (SHED) were grown to confluence and seeded on 3-dimensional tissue engineering scaffolds (BD Biosciences, Franklin Lakes, NJ). The pulp tissue constructs (n=15) were created by seeding SHED on synthetic open-cell D,D-L,L-polylactic acid (OPLA) scaffolds (n=15) and on natural collagen composite scaffolds manufactured from bovine hide (n=15). The negative controls (n=3) were an absence of SHED on OPLA scaffolds. The dental pulp constructs were implanted into a total of 33 human premolar extracted teeth with a single root canal that had been cleaned and shaped using ProTaper rotary instrumentation in a crown-down manner to a size #40 K-file. The teeth containing the pulp tissue constructs were submerged in dulbecco's minimal essential media (DMEM) containing 10% fetal calf serum and antibiotics, maintained at 37 C in a 5% CO-2 atmosphere for 1, 7, and 14 days. The specimens were processed for scanning electron microscopy (SEM). Results: An ultrastructural examination of the SEM micrographs at x2000 magnification revealed SHED adherence within all the scaffolds. The dental pulp constructed created using collagen scaffolds appeared to attach more completely with the root canal walls of the teeth, in comparison with the OPLA scaffolds (X2, P=0.0041). Conclusions: Dental pulp constructs created using collagen tissue engineering scaffolds appeared to be more ideal to attach to the root canal walls. Dental pulp tissue constructs have the potential to adhere inside cleaned and shaped root canals to be used as part of regenerative endodontic treatment. This study was supported by Dentsply, Tulsa Dental.