Title: 0866 - The Pulp-dentin Complex-on-a-chip and 3D Bioprinting of Dentin-derived Hydrogels
Luiz Bertassoni (Presenter)
Oregon Health and Science University
Avathamsa Athirasala, Oregon Health and Science University
Anthony Tahayeri, Oregon Health and Science University
Cristiane França, Oregon Health and Science University
Jack Ferracane, Oregon Health & Science University
Nelson Monteiro, Oregon Health and Science University
Victor Tran, Oregon Health Science University
Ting Zou, Oregon Health and Science University
Amanda Mushashe, Oregon Health & Science University
Greeshma Thrivikraman, Oregon Health & Science University
Objectives: The pulp-dentin complex represents a unique microenvironment that is challenging to replicate. While the dentin matrix is increasingly seen as a dynamic tissue loaded with diffusible factors, the pulp represents a multi-typic tissue under constant fluid-flow, with well-defined 3D architectures, and spatiotemporal chemical gradients. Here we present two novel platforms that highlight these intricacies of the pulp-dentin complex: 1) a novel model of the pulp-dentin on-a-chip, and 2) 3D bioprinted tissue constructs using hydrogels constituted of dentin-derived molecules and growth factors.
Methods: To develop the pulp-dentin on-a-chip we fabricated a poly dimethylsiloxane micro-fluidic device via a micromolding technique. In the microdevice a microchannel was fabricated directed at a chamber containing a precision-cut dentin fragment, which functions as permeable membrane. Across from the dentin fragment, a stem cell-laden photo-tunable hydrogel was loaded through a microfluidic inlet port, and the whole dentin-hydrogel interface perfused with medium through a separate microchannel. The process of fabrication and the resulting cell-viability in the device were characterized. Regarding the 3D bioprinting, a novel hydrogel bioink composed of dentin collagen and alginate hydrogel blends (2:1, 1:1 and 1:2) were mixed with soluble growth factors extracted from mineralized dentin, and bioprinted with SCAP cells. Cell-viability and differentiation were determined using a live/dead assay kit and RT-PCR. Data was analyzed using ANOVA and Tukey.
Results: The pulp-dentin complex on-a-chip was successfully fabricated and maintained under fluid-flow for at least 5d. Sustained cell-viability was observed across the pulp-dentin interface. The 3D bioprinted constructs showed that the alginate-dentin hydrogels with a 1:2 ratio had higher cell-viability, whereas increasing concentrations of dentin-derived growth factors increased the odontogenic differentiation of SCAP in a dose dependent manner.
Conclusions: The pulp-dentin complex on-a-chip and the 3D bioprinted dentin-derived hydrogels can be useful tools for future pulp regeneration studies and translational applications.
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This abstract is based on research that was funded entirely or partially by an outside source:
NIDCR-NIH (R01DE026170 to LEB), the Medical Research Foundation of Oregon (MRF to LEB) and the OHSU Fellowship for Diversity and Inclusion in Research (OHSU-OFDIR to CF)
The submitter must disclose the names of the organizations with which any author have a relationship, the nature of the relationship, and the clinical or research area involved. The following is submitted: NONE