Regeneration of Critical‐Sized Mandibular Defects Using 3D‐Printed Composite Scaffolds: A Quantitative Evaluation of New Bone Formation in In Vivo Studies

Abstract

Mandibular tissue engineering aims to develop synthetic substitutes for the regeneration of critical size defects (CSD) caused by a variety of events, including tumor surgery and post‐traumatic resections. Currently, the gold standard clinical treatment of mandibular resections (i.e., autologous fibular flap) has many drawbacks, driving research efforts toward scaffold design and fabrication by additive manufacturing (AM) techniques. Once implanted, the scaffold acts as a support for native tissue and facilitates processes that contribute to its regeneration, such as cells infiltration, matrix deposition and angiogenesis. However, to fulfil these functions, scaffolds must provide bioactivity by mimicking natural properties of the mandible in terms of structure, composition and mechanical behavior. This review aims to present the state of the art of scaffolds made with AM techniques that are specifically employed in mandibular tissue engineering applications. Biomaterials chemical composition and scaffold structural properties are deeply discussed, along with strategies to promote osteogenesis (i.e., delivery of biomolecules, incorporation of stem cells, and approaches to induce vascularization in the constructs). Finally, a comparison of in vivo studies is made by taking into consideration the amount of new bone formation (NB), the CSD dimensions, and the animal model.

A multifunctional collagen-base bilayer membrane integrated with a bimetallic/polydopamine network for enhanced guided bone regeneration

“…Given that osteogenesis is a gradual process, the degradation results suggested that membranes could act as a durable barrier in bone defects. 37,38 Due to the inherent inflexibility of pure collagen, it may not be suitable for use in GBR membranes. 39 Therefore, HA was added to enhance its mechanical performance.…”

Bioprinting of gelatin-based materials for orthopedic application

“…The present surgical procedures for treating large-size bone deformities involve induced membranes, allografts, autografts, and transfer (bone). However, all the mentioned surgical procedures have drawbacks ( Bezstarosti et al, 2021 ; Dalfino et al, 2023 ). Autografts have the flaws of lack of geometry conformity, secondary morbidity, and a lack of greater graft availability.…”

Calcium Orthophosphate (CaPO4) Containing Composites for Biomedical Applications: Formulations, Properties, and Applications

“…That is why they are called biocomposites and biomaterials. In addition to all that has been previously mentioned, the examples of biomedical applications of CaPO 4 -containing formulations comprise regeneration of critical-sized mandibular defects [1267], orthopedic applications [401], bone revascularization [1268], bone tissue engineering [1269,1270], anti-cancer treatments [1064,1065], etc. Additionally, composite fillers composed of HA and CMC gel possess biostimulatory and skin-tightening properties that have been applied not just to the face but also to the body to boost rejuvenation [900,901].…”