Enhanced Marginal Adaptation of Novel Antimicrobial Nanohybrid Resin Cement

Objectives: To assess the effect of incorporating antimicrobial zein-coated magnesium oxide nanoparticles (zMgO NPs) on the adaptation of self-adhesive resin cement (SARC) using cross-polarization optical coherence tomography (CP-OCT) and Scanning Electron Microscope (SEM).
Methods: Resin inlays were fabricated to be cemented in Class-I cavities of extracted human molars. All specimens were randomly divided into five groups (n=10/gp), and the resin inlays were cemented using SARC with various concentrations of zMgO nanoparticles (0% [control], 0.3%, 0.5%, 1%, 2% by weight) and light-cured (LED device). Characterization of SARC incorporating zMgO NPs was done by X-Ray diffraction (XRD) and Fourier-transform infrared spectroscopy (FTIR). The specimens were stored (37°C, 24hr, humid conditions) before being examined for interfacial adaptation under CP-OCT. Floor and wall adaptation measurements were analyzed by software on 20 B-scans, and samples were sectioned for interfacial measurement by SEM. Statistical analysis done by one-way ANOVA test followed by Mann−Whitney U test (significance p<0.05).
Results: ANOVA results for OCT showed a statistically significant increase of adaptation in the floor (p=0.036) and wall (p=0.043) of SARC filled with zMgO NPs compared to the control. Results were confirmed by SEM analysis (p=0.031, p=0.027, respectively). SARC enhanced with 0.3% and 0.5% showed a statistically significantly better adaptation in floor (p=0.038, p=0.044, respectively) and wall (p=0.039, p=0.048, respectively) in OCT. Similarly in SEM, results were correlated for 0.3% and 0.5% groups (floor: p=0.037, p=0.044; wall: p=0.042, p=0.034, respectively). However, there was no significant difference between the 1%, 2%, and control groups for OCT and SEM analysis (p>0.05). The characterization of the SARC modified with zMgO nanoparticles revealed XRD spectra with no definite diffraction peaks of zMgO. FTIR illustrated no change in the spectra.
Conclusions: The incorporation of antimicrobial zMgO NPs in SARC can enhance the properties of resin cement by significantly improving its wall and floor adaptation.