Lewis Katz School of Medicine at Temple University, Philadelphia, PA.
Columbia University College of Dental Medicine.
J Craniofac Surg. 2021 May 1;32(3):1177-1181. doi: 10.1097/SCS.0000000000007146.
BACKGROUND/PURPOSE: The utilization of three-dimensionally (3D)-printed bioceramic scaffolds composed of beta-tricalcium phosphate in conjunction with dipyridamole have shown to be effective in the osteogenesis of critical bone defects in both skeletally immature and mature animals. Furthermore, previous studies have proven the dura and pericranium's osteogenic capacity in the presence of 3D-printed scaffolds; however, the effect galea aponeurotica on osteogenesis in the presence of 3D scaffolds remains unclear.
METHOD/DESCRIPTION: Critical-sized (11 mm) bilateral calvarial defects were created in 35-day old rabbits (n = 7). Two different 3D scaffolds were created, with one side of the calvaria being treated with a solid nonporous cap and the other with a fully porous cap. The solid cap feature was designed with the intention of preventing communication of the galea and the ossification site, while the porous cap permitted such communication. The rabbits were euthanized 8 weeks postoperatively. Calvaria were analyzed using microcomputed tomography, 3D reconstruction, and nondecalcified histologic sectioning in order assess differences in bone growth between the two types of scaffolding.
Scaffolds with the solid (nonporous) cap yielded greater percent bone volume (P = 0.012) as well as a greater percent potential bone (P = 0.001) compared with the scaffolds with a porous cap. The scaffolds with porous caps also exhibited a greater percent volume of soft tissue (P < 0.001) presence. There were no statistically significant differences detected in scaffold volume.
A physical barrier preventing the interaction of the galea aponeurotica with the scaffold leads to significantly increased calvarial bone regeneration in comparison with the scaffolds allowing for this interaction. The galea's interaction also leads to more soft tissue growth hindering the in growth of bone in the porous-cap scaffolds.
背景/目的：三维（3D）打印的β-磷酸三钙生物陶瓷支架与双嘧达莫联合使用已被证明可有效促进未成年和成年动物的临界骨缺损的成骨作用。此外，先前的研究已经证明了硬脑膜和颅骨在 3D 打印支架存在的情况下具有成骨能力；然而，在 3D 支架存在的情况下，帽状腱膜对成骨的影响尚不清楚。
方法/描述：在 35 天大的兔子（n=7）中创建了 11mm 双侧颅骨临界大小的缺损。创建了两种不同的 3D 支架，一侧颅骨用实心非多孔帽处理，另一侧用完全多孔帽处理。实心帽的特征旨在防止帽状腱膜和骨化部位之间的沟通，而多孔帽允许这种沟通。术后 8 周处死兔子。使用微计算机断层扫描、3D 重建和非脱钙组织切片对颅骨进行分析，以评估两种支架类型之间骨生长的差异。
与具有多孔帽的支架相比，具有实心（非多孔）帽的支架具有更高的骨体积百分比（P=0.012）和更高的潜在骨百分比（P=0.001）。具有多孔帽的支架还表现出更大的软组织体积百分比（P<0.001）。支架体积没有检测到统计学上的显著差异。
物理屏障阻止帽状腱膜与支架的相互作用，与允许这种相互作用的支架相比，可显著增加颅骨的再生。帽状腱膜的相互作用也会导致更多的软组织生长，阻碍多孔帽支架中骨的向内生长。
