A 3D printed TCP/HA structure as a new osteoconductive scaffold for vertical bone augmentation

Abstract Introduction OsteoFlux ® ( OF ) is a 3D printed porous block of layered strands of tricalcium phosphate ( TCP ) and hydroxyapatite. Its porosity and interconnectivity are defined, and it can be readily shaped to conform the bone bed's morphology. We investigated the performance of OF as a scaffold to promote the vertical growth of cortical bone in a sheep calvarial model. Materials and methods Six titanium hemispheres were filled with OF , Bio‐Oss (particulate bovine bone, BO ), or Ceros (particulate TCP , CO ) and placed onto the calvaria of 12 adult sheep (6 hemispheres/sheep). Histomorphometric analyses were performed after 8 and 16 weeks. Results OF led to substantial vertical bone growth by 8 weeks and outperformed BO and CO by a factor 2 yielding OF 22% ± 2.1; BO 11.5% ± 1.9; and CO 12.9% ± 2.1 total new bone. 3 mm away from the bony bed, OF led to a fourfold increase in new bone relative to BO and CO ( n = 8, P < 0.002). At 16 weeks, OF , BO , and CO behaved similarly and showed marked new bone synthesis. A moderate degradation was observed at 16 weeks for all bone substitutes. Conclusion When compared to existing bone substitutes, OF enhances vertical bone growth during the first 2 months after implantation in a sheep calvarial model. The controlled porous structure translated in a high osteoconductivity and resulted in a bone mass 3 mm above the bony bed that was four times greater than that obtained with standard substitutes. These results are promising but must be confirmed in clinical tests.