Effect of Universal Adhesive and Different Surface Pretreatments on Shear Bond Strength of Orthodontic Brackets to Amalgam Restorations: A Comparative Experimental Study

Objectives Many adult patients requiring orthodontic treatment have posterior restorations. Bracket bonding to dental restorations is a clinical challenge. The aim of this study was to compare the effect of universal adhesive with the conventional method on shear bond strength (SBS) of orthodontic brackets to amalgam restorations. Methods Ninety cavities were filled with admixed amalgam and divided into six groups (n=15) according to the surface pretreatment (no mechanical preparation, diamond bur preparation, and sandblasting) and type of bonding agent (alloy primer plus Transbond XT or universal adhesive). Mandibular central incisor brackets were bonded to the restoration surfaces. The primary outcome was the bond strength in megapascals (MPa) which was compared by two-way ANOVA. The mode of failure was the secondary outcome determined by determination of the adhesive remnant index (ARI). The Kruskal-Wallis and Mann-Whitney tests were used to compare the ARI scores among the groups. Results Among the groups with the conventional method, the sandblasted subgroup showed the highest SBS (P<0.05). The three subgroups of universal adhesive were not significantly different in terms of SBS (P=1). Overall, the highest SBS was noted in the sandblasted/conventional adhesive group. Conclusion The results demonstrated that sandblasting plus alloy primer and Transbond XT bonding agent could be recommended for bracket bonding to amalgam restorations. Further studies using other bonding agents are recommende

The Effect of Contact Lens–spectacle Reversed Galilean Telescope on the Visual Field of Patients with Open-angle Glaucoma

Purpose: Glaucoma causes irreversible visual field defects. This study aims to evaluate the effect of a reversed Galilean telescope on the visual field of patients with open-angle glaucoma. Methods: Fifty-two glaucoma patients with a restricted visual field were recruited for this study. Central 30° visual field measurements were performed using a Humphrey visual field analyzer before and after applying the reversed Galilean telescope. To be more cosmetically acceptable, a combination of contact lens–spectacle was used as the reversed Galilean telescope. Results: Our data analysis showed that the reversed Galilean telescope had a significant effect on all measured perimetric indices. Visual field index (VFI) improved from a basic value of 44.38 ± 26.96 percent to 49.30 ± 29.83 percent by using the reversed telescope (P < 0.001). Moreover, the mean deviation (MD) was significantly improved from the initial value of –19.91 ± 7.19 dB to a value of –18.69 ± 7.73 dB (P < 0.001). However, our results showed a significant reduction in the pattern standard deviation (PSD) comparing before (9.83 ± 2.82) and after (8.51 ± 3.30) values using the reversed Galilean telescope (P < 0.001). Conclusion: The contact lens–spectacle combination reversed Galilean telescope significantly improved the central 30° visual field of glaucoma patients with the restricted visual field

Risk-Aware Stochastic Scheduling of Hybrid Integrated Energy Systems with 100% Renewables

Recently, ambitious endeavors have been carried out to facilitate the transition from traditional grids to hybrid interconnected energy networks in the form of grid modernization. Align to such efforts, this article aims at developing a novel framework for satisfying techno-economic-environmental goals in the grid modernization process. To this end, a detailed examination is conducted for the optimal exploitation of energy hubs (EHs) equipped with 100% renewables to pursue the environmental goal alongside intending technical and economic constraints. The energy conversion technology is adopted to enable the power-to-gas system for establishing multi-energy interactions among electricity and gas networks. Fully benefiting from renewable units has exposed the system to uncertain fluctuations that necessitate the modeling of uncertainties to achieve near-reality results. Hence, risk-averse and seeker strategies are developed based on robustness and opportunistic modes of the information gap decision theory (IGDT) method to deal with stochastic fluctuations of uncertain parameters. The integrated electricity and gas test system is considered to analyze the applicability of the proposed framework in modeling efficient multi-energy interactions. Given the obtained results, 43.68% more energy cost is reached for EHs when they adopted a robust strategy against uncertainties under the risk-averse strategy. Moreover, the proposed framework procured a rational decision-making model for balancing multi-energy in the hybrid energy grid with 100% renewables