Evaluation of Helium Plasma Surface Modification on Tensile Bond Strength of Denture Base Materials: A Scanning Electron Microscope Study

Abstract

The purpose of this study was to compare the effect of helium plasma treatment on tensile bond strength between polymethylmethacrylate and soft liner material. For the tensile test, acrylic samples (30 × 10 × 10 mm3; n = 100) were prepared. Acrylic samples were divided into five surface groups (n = 10/group) and treated by different concentrations of helium plasma: G I: Control group (untreated), G II: 100% Helium plasma-treated group, G III: 90% Helium plasma-treated group, G IV: 85% Helium plasma-treated group, G V: 80% Helium plasma-treated group. After plasma treatment, the soft liner was processed between two acrylic resin blocks according to the manufacturer’s instructions and polymerized. The surface properties were evaluated by scanning electron microscopy and atomic force microscopy. All samples were submitted to a tensile test using a universal testing machine. After failure, the surface properties were evaluated by stereomicroscope. One-way analysis of variance was used to compare the groups. p < 0.05 value was considered statistically significant. While the highest mean tensile bond strength value was obtained with the G III (1.56 ± 0.13 MPa), the lowest value was observed with the G I (0.95 ± 0.2 MPa). In addition, it was observed that the surface roughness increased the most in G III.