Towards Polycaprolactone-Based Scaffolds for Alveolar Bone Tissue Engineering: A Biomimetic Approach in a 3D Printing Technique

Abstract

The alveolar bone is a unique type of bone, and the goal of bone tissue engineering (BTE) is to develop methods to facilitate its regeneration. Currently, an emerging trend involves the fabrication of polycaprolactone (PCL)-based scaffolds using a three-dimensional (3D) printing technique to enhance an osteoconductive architecture. These scaffolds are further modified with hydroxyapatite (HA), type I collagen (CGI), or chitosan (CS) to impart high osteoinductive potential. In conjunction with cell therapy, these scaffolds may serve as an appealing alternative to bone autografts. This review discusses research gaps in the designing of 3D-printed PCL-based scaffolds from a biomimetic perspective. The article begins with a systematic analysis of biological mineralisation (biomineralisation) and ossification to optimise the scaffold’s structural, mechanical, degradation, and surface properties. This scaffold-designing strategy lays the groundwork for developing a research pathway that spans fundamental principles such as molecular dynamics (MD) simulations and fabrication techniques. Ultimately, this paves the way for systematic in vitro and in vivo studies, leading to potential clinical applications.

Three-Dimensional-Printed Composite Scaffolds Containing Poly-ε-Caprolactone and Strontium-Doped Hydroxyapatite for Osteoporotic Bone Restoration

“…Mechanical performances need to match those of the host bone tissue, especially in the load-bearing implants [ 31 ], and should have a minimum compressive strength of 2 MPa, a requirement that all tested scaffolds meet [ 36 ]. Other authors mention a possible optimal range of the compressive strength between 2 to 5 Mpa for cancellous bone, 5 and 131 Mpa for alveolar bone, and 131 to 224 Mpa for compact bone [ 37 ]. We took in consideration for this comparison the second inflection point of the stress–strain curve, corresponding to the collapse of material and clogging of the scaffold pores [ 38 ].…”

“…Pristine PCL scaffolds are considered to have an initially very low erosion of less than 1 wt.% in the first month of exposure to physiological conditions. In contrast, composite scaffolds are considered to exhibit weight loss within the first week of exposure to physiological conditions [ 37 ]. Possible initial degradation may have happened to the composite scaffold in contrast with the pristine PCL scaffolds ( Figure 12 ).…”

“…Slightly lower values were observed for pristine PCL scaffolds. This effect may contribute to ameliorating the inflammation caused by the acidic microenvironment usually produced by degradation products of PCL [ 37 ]. Both the increase in degradation of the composite scaffolds compared to simple PCL scaffolds and the increase in pH are advantages that confirm the necessity to incorporate HA/SrHA into PCL scaffolds.…”

Obtaining Polyvinylpyrrolidone Fibers Using the Electroforming Method with the Inclusion of Microcrystalline High-Temperature Phosphates

“…The removal of the scaffold from the body does not require surgery, as the polymer is absorbed and degraded by the body [29]. The inclusion of ceramic materials in the polymer matrix makes it possible to control the rates of degradation and resorption [30].…”