Silver-coated implants curb bone loss in peri-implantitis — but only in mice, so far

Peri-implantitis remains the leading cause of implant failure, and Porphyromonas gingivalis plays a central role in its pathogenesis. This study examined whether silver ion (Ag⁺)-coated titanium implants could prevent P. gingivalis-driven peri-implantitis and associated bone loss.

The implant coating consisted of Ag⁺ ions deposited on a hydroxyapatite film chelated with inositol hexaphosphate (IP6) — a design that anchors the silver ions to the implant surface while providing controlled release. In vitro testing using a Ti wire configuration demonstrated significant antibacterial activity against P. gingivalis in inhibition zone assays (n=4 per group).

The in vivo arm employed a murine model of ligature-induced peri-implantitis. Ag⁺-coated implants significantly reduced alveolar bone resorption compared to uncoated titanium controls. Quantitatively, the control group showed bone loss of 19-25% relative to baseline at day 28, while the Ag⁺-coated group exhibited only 15-20% bone loss (n=8 per group per time point).

While these results are preclinical and the murine model has inherent limitations in translating to human peri-implantitis, the study provides proof-of-concept that surface modification with Ag⁺ ions can confer meaningful antibacterial protection against a key periodontal pathogen. The IP6-hydroxyapatite chelation platform is a practical coating strategy that could potentially be integrated into existing implant manufacturing processes. These findings add to the growing body of evidence supporting bioactive implant surface modifications as a preventive strategy against peri-implantitis-associated bone loss.