Advances in Biodegradable 3D Printed Scaffolds with Carbon-Based Nanomaterials for Bone Regeneration

Abstract

A pesar de que el tejido óseo tiene la capacidad innata de auto-regenerarse, hay casos críticos en los que su capacidad de regeneración se ve comprometida. Este es, por ejemplo, el caso de fracturas graves con tamaños críticos (≥ 2.5 mm) o fracturas irregulares creados por trauma, infección, resección tumoral o anomalías esqueléticas; o también casos en los que el proceso regenerativo se ve comprometido, como por ejemplo la necrosis avascular o la osteoporosis. En estos casos, cuando el proceso natural de curación y regeneración ósea se ve inhibido, el tratamiento por excelencia es la utilización de injertos.

Bone possesses an inherent capacity to fix itself. However, when a defect larger than a critical size appears, external solutions must be applied. Traditionally, an autograft has been the most used solution in these situations. However, it presents some issues such as donor-site morbidity. In this context, porous biodegradable scaffolds have emerged as an interesting solution. They act as external support for cell growth and degrade when the defect is repaired. For an adequate performance, these scaffolds must meet specific requirements: biocompatibility, interconnected porosity, mechanical properties and biodegradability. To obtain the required porosity, many methods have conventionally been used (e.g., electrospinning, freeze-drying and salt-leaching). However, from the development of additive manufacturing methods a promising solution for this application has been proposed since such methods allow the complete customisation and control of scaffold geometry and porosity. Furthermore, carbon-based nanomaterials present the potential to impart osteoconductivity and antimicrobial properties and reinforce the matrix from a mechanical perspective. These properties make them ideal for use as nanomaterials to improve the properties and performance of scaffolds for bone tissue engineering. This work explores the potential research opportunities and challenges of 3D printed biodegradable composite-based scaffolds containing carbon-based nanomaterials for bone tissue engineering applications.