Jarvie Journal - College of Dental Medicine - Columbia University

Multiphase Bioscaffold for Integrated Regeneration of Root-Periodontium Complex
Jeffrey Hajibandeh 1 , Chang H. Lee 1,2 , Jeffrey Ahn 1,2 , Andrew Fan 1,2 , Jeremy J. Mao 1,2 *
1 College of Dental Medicine, Columbia University, New York, NY,
2 Center for Craniofacial Regeneration, College of Dental Medicine
Columbia University, New York, NY; *Faculty Mentor
Objectives: Regeneration of root and periodontium holds a promise to overcome current limitations of dental implant
therapy, including its dependence upon supporting bone structure and lack of biological integration and remodeling with
host alveolar bone. Here, we develop an integrated scaffold with multiphase microstructure and spatial-delivered
bioactive cues, and its potential in generating root-periodontium complex from dental stem/progenitor cells is tested both
in vitro and in vivo.
Materials and Methods: Polycaprolactone (PCL)-hydroxylapatite (HA) (90:10wt%) scaffolds were fabricated
(5×5×3mm 3 ) using 3D printing per our prior works. The scaffolds consisted of three phases: A) 100µm microchannels
with 2.25mm in width, B) 600µm microchannels with 500µm in width, and C) 300µm microchannels with 2.25mm in
width. Phases A, B, and C were designed to guide formation of dentin/cementum, periodontal ligament (PDL), and
alveolar bone, respectively. To promote cell differentiation, PLGA microspheres encapsulated with Amelogenin, CTGF,
and BMP2 were incorporated in phase A, B, and C of the scaffolds, respectively. To test various cell types and their
responses, scaffolds were seeded with human dental pulp stem/progenitor cells (DPSCs), periodontal ligament
stem/progenitor cells (PDLSCs), or alveolar bone stem/progenitor cells (ABSCs) with approximately 100,000 cells per
scaffold. In vitro scaffolds were grown in modified DMEM media, while in vivo scaffolds were implanted
subcutaneously into nude mice. Both models were harvest at four weeks and multiphase tissue formation in the scaffolds
was evaluated by multitude of assays.
Results and Conclusions: Immuno-/histomorphometric analysis demonstrated that multiphase scaffold microstructure
with spatial-delivered bioactive cues successfully generated multiphase putative tissues consisting of collagen I-rich
fibrous matrix (Phase B) sandwiched between mineralized regions in both in vitro and in vivo (Phase A and C). DSPpositive
mineralized structure in Phase C was highly dense and polarized (reminiscent of native dentin) in comparison
with that of Phase C. DPSC’s were superior to the other cell types in mineralization, whereas PDLSC’s yielded highly
aligned fibrous structure as compared to the other cell types. In vivo results further demonstrated highly aligned fibrous
tissues inserting into CEMP + mineralized matrix. PCR demonstrated amplified levels of tissue specific markers in the
GF+ scaffolds: Phase A (putative alveolar bone) expressed relatively high levels of BSP (p