Bioactive Surface Modifications on Bioresorbable Bone Screws: A Step Forward in Orthopedic Surgery

Area of Science:

• Biomaterials Science
• Orthopedic Surgery
• Tissue Engineering

Background:

• Current orthopedic implants often use metals with poor biocompatibility due to mechanical property mismatch.
• Biodegradable, non-toxic, and non-immunogenic materials offer superior clinical potential.
• Developing advanced biomaterials is crucial for improving orthopedic implant outcomes.

Purpose of the Study:

• To construct and evaluate polylactide screws coated with collagen, nanohydroxyapatite, and polylactide, with and without silver nanowires.
• To assess the physico-chemical and biological properties of these novel coated screws.
• To determine the efficacy of the bioactive coatings in enhancing bone regeneration and biocompatibility.

Main Methods:

• Fabrication of polylactide screws with collagen, nanohydroxyapatite, and polylactide coatings, including a silver nanowire variant.
• In vitro analysis of cell adhesion, proliferation, and cytotoxicity using human osteosarcoma cells (2T line).
• In vivo evaluation of screw safety and efficacy in minipig metatarsal bone implantation models.

Main Results:

• Coated screw surfaces supported human osteosarcoma cell growth.
• Cytotoxicity assays confirmed the non-toxic nature of the coatings, promoting cell adhesion and proliferation.
• In vivo studies demonstrated accelerated bone tissue regeneration, increased bone-to-granulation tissue ratio, reduced inflammation, and enhanced osteoblast/osteoclast activity compared to controls.

Conclusions:

• The developed bioactive coatings significantly enhance the biocompatibility of orthopedic implants.
• These coatings promote faster bone regeneration and improve osteointegration.
• The findings support the clinical potential of these advanced biomaterials for orthopedic applications.