Efficacy and safety of the low-temperature-derived 3D printed biodegradable Mg-containing composite porous scaffold for bone defect repair: A prospective and multi-center randomized controlled trial.

Abstract

Achieving effective bone regeneration of critical-size bone defects resulted from either trauma or metabolic disorders is a big clinical challenge. Biodegradable and bioactive bone substitutes designed for filling up bone defects to enhance osteogenesis and angiogenesis have become the focus for clinical use over the past few decades. We developed a novel porous composite scaffold (known as Bongolle®) is composed of bioactive magnesium (Mg), poly(lactide-co-glycolide) (PLGA) and β-tricalcium phosphate (β-TCP). We fabricated Bongolle® by a unique low-temperature rapid prototyping (LT-RP) technology with a well-designed biomimetic structure. We then tested Bongolle® in a multi-centered, prospective randomized controlled trial (RCT). The RCT suggests that The Bongolle® group demonstrated a 40 % faster scaffold residual bone fusion rate at 12 weeks post-surgery compared to the control group (χ² = 10.175, P < 0.01). By 24 weeks post-surgery, both groups exhibited a similar fusion rate (χ² = 1.101, P > 0.05). Radiographic density of the implanted scaffolds revealed that the Bongolle® group experienced a 9.29 ± 17.80 % increase at 12 weeks and a 12.68 ± 21.86 % increase at 24 weeks post-surgery (P < 0.01), while the control group showed no significant changes. These findings suggest that Bongolle® is a promising bioadaptive scaffold material for inducing scaffold fusion with the local host bone and new bone regeneration accompanied by scaffold degradation with its implantation overtime. This study is the first RCT to report that Bongolle® has strong potential for future clinical applications where it might synergistically facilitate bone regeneration and early healing in critical-size bone defects.