Rational design of nonstoichiometric bioceramic scaffolds via digital light processing: tuning chemical composition and pore geometry evaluation

Abstract

Bioactive ceramics are promising candidates as 3D porous substrates for bone repair in bone regenerative medicine. However, they are often inefficient in clinical applications due to mismatching mechanical properties and compromised biological performances. Herein, the additional Sr dopant is hypothesized to readily adjust the mechanical and biodegradable properties of the dilute Mg-doped wollastonite bioceramic scaffolds with different pore geometries (cylindrical-, cubic-, gyroid-) by ceramic stereolithography. The results indicate that the compressive strength of Mg/Sr co-doped bioceramic scaffolds could be tuned simultaneously by the Sr dopant and pore geometry. The cylindrical-pore scaffolds exhibit strength decay with increasing Sr content, whereas the gyroid-pore scaffolds show increasing strength and Young’s modulus as the Sr concentration is increased from 0 to 5%. The ion release could also be adjusted by pore geometry in Tris buffer, and the high Sr content may trigger a faster scaffold bio-dissolution. These results demonstrate that the mechanical strengths of the bioceramic scaffolds can be controlled from the point at which their porous structures are designed. Moreover, scaffold bio-dissolution can be tuned by pore geometry and doping foreign ions. It is reasonable to consider the nonstoichiometric bioceramic scaffolds are promising for bone regeneration, especially when dealing with pathological bone defects.

Precisely Tuning the Pore-Wall Surface Composition of Bioceramic Scaffolds Facilitates Angiogenesis and Orbital Bone Defect Repair

“…The porous architectures of bioceramic scaffolds were designed by computer-assisted design (Materialise Magics 21.0) and then fabricated by DLP-based 3D printing (Ten Dimensions Technology Co., Beijing) . The 3D porous model (8 mm × 10 mm × 2 mm; Scheme A) with an appropriate pore size (350–500 μm) and a smooth curve on one side could readily match the defect cavity and new bone tissue ingrowth.…”

“…The porous architectures of bioceramic scaffolds were designed by computer-assisted design (Materialise Magics 21.0) and then fabricated by DLP-based 3D printing (Ten Dimensions Technology Co., Beijing). 38 The 3D porous model (8 mm × 10 mm × 2 mm; Scheme 1A) with an appropriate pore size (350−500 μm) 39 and a smooth curve on one side could readily match the defect cavity and new bone tissue ingrowth. After undergoing ultrasonic cleaning and hot-air drying at 60 °C, the printed 3D porous bodies were sintered at 1150 °C for 2 h in a microcontroller-controlled temperature furnace (Kejing Co., Hefei, Anhui, China) with a temperature rising rate of 2 °C/min followed by naturally cooling.…”

Additive Manufacturing of Bioceramic Implants for Restoration Bone Engineering: Technologies, Advances, and Future Perspectives

“…This provided a novel direction for the design of bionic structures for implants. Lv et al 140 designed three structures including cylindrical, lithophane, and TPMS, and controlled the implant porosity at ∼58% and pore size at ∼600 μm. The implants were accurately prepared by DLP.…”

“…Schematic design of the graded TPMS stents. a) Designed 3D pore shape of the porous models and pore unit cells (cylindrical, cubic, and gyroid) . Reproduced with permission from ref .…”

Preparation of BMP-2/PDA-BCP Bioceramic Scaffold by DLP 3D Printing and its Ability for Inducing Continuous Bone Formation

“… Zhang et al (2020) recently prepared a structurally diversified Haversian bone-mimicking scaffold via DLP-based 3D printing using bioceramic Ca2MgSi2O7, which is hard to fabricate through the FDM printing method. However, the existing published reports mainly dealt with the fabrication process and parameters of DLP printed bioceramic scaffold, but lack the subsequent systematic biological evaluations for bone regeneration application ( Li et al, 2021 ). Recently, there is a growing interest in developing HA/β-TCP biphasic calcium phosphate (BCP) bioceramics as bone scaffolding materials because they are more effective in bone regeneration than pure HA or pure ß -TCP, and have a controllable degradation rate ( Kim and Park, 2020 ).…”