Safety and efficacy of PLGA(Ag-Fe<sub>3</sub>O<sub>4</sub>)-coated dental implants in inhibiting bacteria adherence and osteogenic inducement under a magnetic field

Abstract

Introduction: The placement of dental implants is performed in a contaminated surgical field in the oral cavity, which may lead to implant failure. Bacterial adhesion and proliferation ( Streptococcus mutans, Porphyromonas gingivalis ) often lead to implant infections. Although Ag nanoparticles hold great promise for a broad spectrum of antibacterial activities, their runoff from dental implants compromises their antibacterial efficacy and potentially impairs osteoblast proliferation. Thus, this aspect remains a primary challenge and should be controlled. Materials and methods: In this study, PLGA(Ag-Fe 3 O 4 ) was modified on the implanted tooth surface and was characterized by transmission electron microscopy, X-ray diffraction, and Fourier transform infrared spectroscopy. The magnetic and antibacterial properties were also determined. Results: Results showed that Ag successfully bonded with Fe 3 O 4 , and Ag-Fe 3 O 4 not only exerted superparamagnetism but also exhibited antibacterial activity almost identical to silver nanoparticles (nano-Ag). The PLGA(Ag-Fe 3 O 4 ) coating could significantly maintain the antibacterial activity and avoid bacterial adhesion to the implant. Compared with the blank control group, PLGA(Ag-Fe 3 O 4 ) under magnetic field-coated samples had a significantly lower amount of colonized S. mutans ( P <0.01). Osteoblast proliferation results showed that the coated samples did not exhibit cytotoxicity and could promote osteoblast proliferation as shown by MTT, alkaline phosphatase, and the nucleolar organizer region count. Conclusion: We developed a novel Ag biologically compatible nanoparticle in this study without compromising the nano-Ag antibacterial activity, which provided continuous antibacterial action. Keywords: Ag-Fe 3 O 4 , PLGA, dental implants, antibacterial property Corrigendum for this paper has been published