Revolutionizing Mg-based guided bone regeneration mesh derived from endogenous dentoalveolar bone augmentation.

Abstract

Ideal regeneration of alveolar bone remains challenging due to its irregular morphology, complex structure, and unique biological functions. Advances in computer-aided design (CAD) and additive manufacturing (AM) have facilitated the development of customized bone grafts, making the repair of complex alveolar defects feasible. Magnesium (Mg) alloys with biodegradability, excellent osteogenesis and mechanical properties have been in high demand for guided bone regeneration (GBR) applications. However, the clinical application of Mg alloys is hindered by rapid degradation. Thus, this study developed a customized Mg-alloy GBR mesh via digital modeling and laser powder bed fusion (LPBF), with a strontium-doped octacalcium phosphate (SrOCP) coating to regulate degradation and osteogenesis. Sustained release of Mg²⁺ and Sr²⁺ activated the PI3K/Akt pathway, significantly promoting endogenous bone regeneration. In beagle models, the mesh achieved effective repair of alveolar defects (15 mm × 8 mm × 5 mm) without extra collagen membranes or bone substitutes. It showed controlled degradation (92.16% volume retention at 4 weeks, >80% degradation at 12 weeks) and strong osteogenic capability (new bone volume fraction 86.89% at 12 weeks). Collectively, a promising GBR strategy with biodegradable LPBF Mg-alloy mesh to facilitate the alveolar bone regeneration is proposed.