E-cigarette Aerosol Mixtures Inhibit Biomaterial-Induced Osseointegrative Cell Phenotypes

Area of Science:

• Biomaterials Science
• Cell Biology
• Dental Implantology

Background:

• Cigarette smoking is a known risk factor for dental implant failure.
• The rising popularity of e-cigarettes necessitates understanding their impact on implant biology.
• Limited research exists on how e-cigarette aerosol mixtures (ecig-AM) affect cellular responses to implant materials.

Purpose of the Study:

• To investigate the effect of ecig-AM on macrophage activation.
• To assess the impact of ecig-AM on mesenchymal stem cell (MSC) osteoblastogenesis.
• To examine these cellular responses on titanium (Ti) implant surfaces with varying topographies.

Main Methods:

• Macrophages and MSCs were exposed to ecig-AM on smooth, rough-hydrophobic, or rough-hydrophilic Ti surfaces.
• Macrophage inflammatory markers and immunophenotype were analyzed.
• MSC osteogenic marker expression, inflammatory cytokine secretion, and alkaline phosphatase activity were measured.

Main Results:

• Ecig-AM induced a pro-inflammatory macrophage phenotype, amplified by flavorants and nicotine.
• MSC metabolic activity decreased concentration-dependently, particularly with nicotine-containing ecig-AM.
• MSCs showed reduced osteogenic marker expression and increased RANKL secretion, with effects mitigated on rough-hydrophilic surfaces.

Conclusions:

• Ecig-AM promotes macrophage inflammation and impairs MSC differentiation into osteoblasts on Ti surfaces.
• Nicotine and flavorants in ecig-AM potentiate these adverse effects.
• E-cigarette use may negatively impact dental implant osseointegration, especially on certain surface topographies.