Bioactive Scaffolds as a Promising Alternative for Enhancing Critical-Size Bone Defect Regeneration in the Craniomaxillofacial Region

Abstract

Reconstruction of critical-size bone defects (CSDs) in the craniomaxillofacial (CMF) region remains challenging. Scaffold-based bone-engineered constructs have been proposed as an alternative to the classical treatments made with autografts and allografts. Scaffolds, a key component of engineered constructs, have been traditionally viewed as biologically passive temporary replacements of deficient bone lacking intrinsic cues to promote osteogenesis. Nowadays, scaffolds are functionalized, giving rise to bioactive scaffolds promoting bone regeneration more effectively than conventional counterparts. This review focuses on the three approaches most used to bioactivate scaffolds: (1) conferring microarchitectural designs or surface nanotopography; (2) loading bioactive molecules; and (3) seeding stem cells on scaffolds, providing relevant examples of in vivo (preclinical and clinical) studies where these methods are employed to enhance CSDs healing in the CMF region. From these, adding bioactive molecules (specifically bone morphogenetic proteins or BMPs) to scaffolds has been the most explored to bioactivate scaffolds. Nevertheless, the downsides of grafting BMP-loaded scaffolds in patients have limited its successful translation into clinics. Despite these drawbacks, scaffolds containing safer, cheaper, and more effective bioactive molecules, combined with stem cells and topographical cues, remain a promising alternative for clinical use to treat CSDs in the CMF complex replacing autografts and allografts.

Bioactive gelatin-sheets as novel biopapers to support prevascularization organized by laser-assisted bioprinting for bone tissue engineering

“…lack of availability, poor biological properties) and risks (e.g. infections, pain, immunogenicity) [3]. Tissue engineering strategies have been proposed as promising alternatives to overcome the issues related to the use of current therapeutics and to produce bone substitutes that mimic the complexity, structure, and functionality of native bone.…”