Effect of Cold Atmospheric Plasma Treatment on the Bond Strength of Glass Fiber Posts

Abstract

This study assesses the impact of air dielectric barrier discharge (DBD) cold atmospheric plasma (CAP) on the push-out bond strength of glass fiber posts (GFPs) compared to silane and hydrofluoric (HF) treatments. The surfaces of GFPs were subjected to silane, HF, and CAP treatments, and the effects of these treatments were evaluated using contact angle measurements. Additionally, scanning electron microscopy (SEM) was used to visualize the effects of silane, HF, and CAP treatments on the GFP surfaces. GFPs treated with various surface treatments were then placed in post spaces within root canals, and push-out bond strength was measured at the cervical, middle, and apical regions of the root canal. CAP treatment rendered the surfaces of GFPs superhydrophilic, with a measured contact angle of 0°, while silane and HF-treated surfaces had contact angles of 110.5° and 101.3°, respectively. SEM images revealed that CAP treatment increased the surface roughness of GFPs without damaging the glass fibers, whereas HF treatment caused breakage of exposed glass fibers, and silane covered the GFP surfaces. The push-out bond strength in all regions of the root canal was significantly higher in the CAP-treated group, with an overall bond strength improvement of approximately 3.5-fold compared to the control group. CAP treatment, by inducing superhydrophilicity and enhancing surface roughness without damaging glass fibers, substantially increased the bond strength of GFPs. Consequently, CAP may be considered a state-of-the-art surface treatment technique for enhancing the bond strength of GFPs, offering superior bonding strength of dental posts via superhydrophilicity compared to conventional methods and potentially leading to improved clinical outcomes.