A Biomimetic Multifunctional Scaffold for Infectious Vertical Bone Augmentation.

Abstract

The regenerative treatment of infectious vertical bone defects remains difficult and challenging today. Current clinical treatments are limited in their ability to control bacteria and infection, which is unfavorable for new bone formation and calls for a new type of material with excellent osteogenic and antibacterial properties. Here a multifunctional scaffold is synthesized that mimics natural bone nanostructures by incorporating silver nanowires into a hierarchical, intrafibrillar mineralized collagen matrix (IMC/AgNWs), to achieve the therapeutic goals of inhibiting bacterial activity and promoting infectious alveolar bone augmentation in rats and beagle dogs. An appropriate concentration of 0.5 mg mLAgNWs is selected to balance biocompatibility and antibacterial properties. The achieved IMC/AgNWs exhibit a broad spectrum of antimicrobial properties against Gram-negative Porphyromonas gingivalis and Gram-positive Streptococcus mutans. When the IMC/AgNWs are cocultured with periodontal ligament stem cells, it possesses excellent osteoinductive activities under both non-inflammatory and inflammatory conditions. By constructing a rat mandibular infected periodontal defect model, the IMC/AgNWs achieve a near-complete healing through the canonical BMP/Smad signaling. Moreover, the IMC/AgNWs enhance vertical bone height and osseointegration in peri-implantitis in beagle dogs, indicating the clinical translational potential of IMC/AgNWs for infectious vertical bone augmentation.