Related Experiment Video
Updated: Dec 30, 2025
Author Spotlight: Development and Evaluation of a Standardized Rat Model for Calvarial Suture-Bony Composite Defects
Published on: May 10, 2024
Bone Tissue Engineering in the Growing Calvaria Using Dipyridamole-Coated, Three-Dimensionally-Printed Bioceramic
Samantha G Maliha1, Christopher D Lopez1, Paulo G Coelho1
1From the Hansjörg Wyss Department of Plastic Surgery, New York University Langone Health; New York University School of Medicine; the Icahn School of Medicine at Mount Sinai; the Department of Biomaterials, New York University College of Dentistry; and the Division of Translational Medicine, New York University School of Medicine.
Background:
Three-dimensionally-printed bioceramic scaffolds composed of β-tricalcium phosphate delivering the osteogenic agent dipyridamole can heal critically sized calvarial defects in skeletally mature translational models. However, this construct has yet to be applied to growing craniofacial models. In this study, the authors implanted three-dimensionally-printed bioceramic/dipyridamole scaffolds in a growing calvaria animal model and evaluated bone growth as a function of geometric scaffold design and dipyridamole concentration. Potential adverse effects on the growing suture were also evaluated.
Methods:
Bilateral calvarial defects (10 mm) were created in 5-week-old (approximately 1.1 kg) New Zealand White rabbits (n = 16 analyzed). Three-dimensionally-printed bioceramic scaffolds were constructed in quadrant form composed of varying pore dimensions (220, 330, and 500 μm). Each scaffold was coated with collagen and soaked in varying concentrations of dipyridamole (100, 1000, and 10,000 μM). Controls consisted of empty defects. Animals were killed 8 weeks postoperatively. Calvariae were analyzed using micro-computed tomography, three-dimensional reconstruction, and nondecalcified histologic sectioning.
Results:
Scaffold-induced bone growth was statistically greater than bone growth in empty defects (p = 0.02). Large scaffold pores, 500 μm, coated in 1000 μM dipyridamole yielded the most bone growth and lowest degree of scaffold presence within the defect. Histology showed vascularized woven and lamellar bone along with initial formation of vascular canals within the scaffold lattice. Micro-computed tomographic and histologic analysis revealed patent calvarial sutures without evidence of ectopic bone formation across all dipyridamole concentrations.
Conclusion:
The authors present an effective pediatric bone tissue-engineering scaffold design and dipyridamole concentration that is effective in augmentation of calvarial bone generation while preserving cranial suture patency.
