The revascularization of grafted tissues is a complicated and non-straightforward process, which makes it challenging to perform reconstructive surgery for critical-sized bone defects. This challenge is combined with the low vascularity that results from radiotherapy. This low vascularity could result from ischemia–reperfusion injuries, also known as ischemia which may happen upon grafting. Ischemia may affect the hard tissue during reconstruction, and this can often cause resorption, infections, disfigurement, and malunion. This paper therefore reviews the clinical and experimental application of procedures that were employed to improve the reconstructive surgery process, which would ensure that the vascularity of the tissue is maintained or enhanced. It also presents the key strategies that are implemented to perform tissue engineering within the grafted sites aiming to optimize the microenvironment and to enhance the overall process of neovascularization and angiogenesis. This review reveals that the current strategies, according to the literature, are the seeding of the mature and progenitor cells, use of extracellular matrix (ECM), co-culturing of osteoblasts with the ECM, growth factors and the use of microcapillaries incorporated into the scaffold design. However, due to the unstable and regression-prone capillary structures in bone constructs, further research focusing on creating long-lasting and stable blood vessels is required.

Graphical Abstract

中文翻译：

---

颅面部骨生物工程的血运重建和血管生成：综述

移植组织的血运重建是一个复杂且非直接的过程，这使得对临界尺寸的骨缺损进行重建手术具有挑战性。这一挑战与放射治疗导致的低血管分布相结合。这种低血管供应可能是由于缺血再灌注损伤（也称为移植时可能发生的缺血）造成的。缺血可能会在重建过程中影响硬组织，这通常会导致吸收、感染、毁容和畸形愈合。因此，本文回顾了用于改进重建手术过程的程序的临床和实验应用，这将确保维持或增强组织的血管分布。它还介绍了在移植部位进行组织工程的关键策略，旨在优化微环境并增强新血管形成和血管生成的整体过程。这篇综述表明，根据文献，目前的策略是成熟细胞和祖细胞的接种、细胞外基质 (ECM) 的使用、成骨细胞与 ECM 的共培养、生长因子以及使用微毛细血管并入细胞中。脚手架设计。然而，由于骨骼结构中的毛细血管结构不稳定且容易退化，因此需要进一步研究以创建持久且稳定的血管。这篇综述表明，根据文献，目前的策略是成熟细胞和祖细胞的接种、细胞外基质 (ECM) 的使用、成骨细胞与 ECM 的共培养、生长因子以及使用微毛细血管并入细胞中。脚手架设计。然而，由于骨骼结构中的毛细血管结构不稳定且容易退化，因此需要进一步研究以创建持久且稳定的血管。这篇综述表明，根据文献，目前的策略是成熟细胞和祖细胞的接种、细胞外基质 (ECM) 的使用、成骨细胞与 ECM 的共培养、生长因子以及使用微毛细血管并入细胞中。脚手架设计。然而，由于骨骼结构中的毛细血管结构不稳定且容易退化，因此需要进一步研究以创建持久且稳定的血管。

图形概要