Allylamine coating on zirconia dental implant surface promotes osteogenic differentiation in vitro and accelerates osseointegration in vivo

Objectives: The glow discharge plasma (GDP) procedure has proven efficacy in grafting allylamine onto zirconia dental implant surfaces to enhance osseointegration. This study explored the enhancement of zirconia dental implant properties using GDP at different energy settings (25, 50, 75, 100, and 200 W) both in vitro and in vivo. Materials and Methods: In vitro analyses included scanning electron microscopy, wettability assessment, energy-dispersive X-ray spectroscopy, and more. In vivo experiments involved implanting zirconia dental implants into rabbit femurs and later evaluation through impact stability test, micro-CT, and histomorphometric measurements. Results: The results demonstrated that 25 and 50 W GDP allylamine grafting positively impacted MG-63 cell proliferation and increased alkaline phosphatase activity. Gene expression analysis revealed upregulation of OCN, OPG, and COL-I. Both 25 and 50 W GDP allylamine grafting significantly improved zirconia's surface properties (p <.05, p <.01, p <.001). However, only 25 W allylamine grafting with optimal energy settings promoted in vivo osseointegration and new bone formation while preventing bone level loss around the dental implant (p <.05, p <.01, p <.001). Conclusions: This study presents a promising method for enhancing Zr dental implant surface's bioactivity.