posted on 2020-03-20, 13:12authored bySunil
Kumar Boda, Hongjun Wang, Johnson V. John, Richard A. Reinhardt, Jingwei Xie
The fixation and
stability of dental implants is governed by the
quality of the underlying alveolar bone. The current study investigates
if the dual delivery of calcium chelating bone therapeutics from mineralized
nanofiber fragments can help regenerate alveolar bone in vivo. Alendronate (ALN) or/and bone morphogenetic protein-2-mimicking
peptide conjugated to a heptaglutamate moiety (E7-BMP-2) were incorporated
onto mineralized nanofiber fragments of polylactide-co-glycolide–collagen–gelatin (PCG in 2:1:1 weight ratios)
via calcium coupling/chelation. Two mg of the single-loaded (ALN)
and coloaded (ALN + E7-BMP-2) mineralized nanofiber PCG grafts was
filled into critical-sized (2 mm diameter × 2 mm depth) alveolar
bone defects in rat maxillae and let heal for 4 weeks. X-ray microcomputed
tomography analysis of the retrieved maxillae revealed significantly
elevated new bone formation parameters for the ALN and ALN + E7-BMP-2
groups compared with the unfilled defect controls. However, no significant
differences between the single and coloaded nanofiber grafts were
noted. Furthermore, the histopathological analysis of the tissue sections
divulged islands of new bone tissue in the ALN and ALN + E7-BMP-2
groups, whereas the control defect was covered with gingival tissue.
Together, the presented strategy using mineralized nanofiber fragments
in the sustained delivery of dual calcium chelating therapeutics could
have potential applications in enhancing bone regeneration.