This study evaluated the effect of dentin surface treatment on the micromorphology and shear bond strength (SBS) of a self-adhering flowable composite, Vertis Flow (VF). Flat dentin surfaces obtained from sixty extracted human molars were divided into six groups (n = 10) according to the following surface treatments: (G1) control, no treatment; (G2) self-etching adhesive, Optibond All-in-One; (G3) phosphoric acid etching for 15 s; (G4) polyacrylic acid for 10 s; (G5) EDTA for 60 s; and G6) sodium hypochlorite (NaOCl) for 15 s. After restoration using VF, SBS was measured in MPa. Data were analyzed using one-way ANOVA and Tamhane test (α = 0.05). Six additional specimens were prepared for scanning electron microscopy analysis. SBS was significantly affected by surface treatment (P < 0.001). SBS of six groups from the highest to the lowest were as follows: (G3) 13.5(A); (G5) 8.98(AB); (G2) 8.85(AB); (G4) 8.21(AB); (G1) 7.53(BC); and (G6) 4.49(C) (groups with the same superscript letter were statistically similar). Morphological analysis revealed numerous long resin tags at the adhesive interface for acid-etched group, with a few short resin tags for the control group and small gap formation for NaOCl-treated group. In conclusion, dentin surface treatments tested differently affected bonding performance of VF; only acid-etching effectively improved this.
The purpose of this study was to evaluate the performance of a resin-modified glass ionomer cement (RMGIC) to which bacterial cellulose nanocrystals (BCNs) were added. BCNs were incorporated into the RMGIC powder in ratios of 0.3%, 0.5%, and 1% (w/w). One control and three experimental groups were enrolled in the study: unmodified RMGIC (control), 0.3% (w/w) BCN-modified RMGIC, 0.5% (w/w) BCN-modified RMGIC, and 1% (w/w) BCN-modified RMGIC. The surface hardness and surface roughness were the parameters assessed. The materials were characterized by scanning electron microscopy (SEM). The data were analyzed using the one-way ANOVA and Kruskal–Wallis tests for surface hardness and roughness, respectively. The addition of BCN resulted in the improvement of surface roughness in all the specimens compared with the control material. The RMGIC modified by 1% (w/w) BCN showed the lowest surface roughness (decreased by 52%) among all tested groups. However, BCN had a negative effect on the surface hardness of RMGIC. The group with 0.3% (w/w) BCN had the least decrease in microhardness (13%). According to the results, the RMGIC group modified by 1% (w/w) BCN had a smoother surface than the other groups. The surface microhardness of the RMGIC decreased after BCNs were added to it.
Objectives The purpose of this study was to evaluate the effect of bacterial cellulose nanocrystals (BCNCs) on the mechanical properties of resin-modified glass ionomer cements (RMGICs) including compressive strength (CS), diametral tensile strength (DTS), and modulus of elasticity (E). Materials and Methods BCNCs were incorporated into RMGIC at various concentrations (0.3, 0.5, and 1 wt%). Unmodified RMGIC was used as the control group. The specimens were stored in distilled water at 37°C for 24 hours. CS and DTS, as well as modulus of elasticity, were evaluated using a universal testing machine. The nanostructure of BCNCs was observed via field emission scanning electron microscopy. Statistical Analysis One-way analysis of variance and post-hoc Tukey tests were used for data analysis. Level of significance was at p < 0.05. Results The addition of BCNCs to RMGIC led to an increase in all of the tested mechanical properties compared with the control group, with a significant increase observed for 1 wt% BCNC. CS and DTS improved up to 23%, and modulus of elasticity increased by 44%. Conclusions The addition of BCNCs to the RMGIC improved the mechanical properties, including CS, elastic modulus, and DTS. Thus, the newly developed RMGICs with BCNCs might represent an ideal and promising novel dental material in restorative dentistry.
BackgroundThis study evaluated the effect of three different silanes and post-silanization treatments on the retentive strength of fiber posts luted with an etch-and-rinse resin cement.Material and MethodsOne hundred intact maxillary central incisors were randomly divided into 10 groups after endodontic treatment and post space preparation (n=10). The fiber posts were etched using 24% hydrogen peroxide. Posts of the control group did not receive silane. In nine experimental groups, each of the three silanes used, Scotchbond Universal adhesive, Bis-Silane and Porcelain Primer, was subjected to three treatments: air-drying at 25°C, warm air-drying and CO2 laser heat treatment. After cementation of the treated posts using One-Step Plus/Duo-Link cement, the specimens were stored for one weak and then subjected to pull-out bond strength (PBS) testing. The data in Newton (N) were analyzed using two-way ANOVA and Tukey tests (α=0.05).ResultsPBS was significantly affected by silane type and post-silanization treatment (p<0.001). The interaction of the two factors was not statistically significant (p=0.15). The effect of Porcelain Primer on PBS was significantly higher than those of universal adhesive (p<0.001) and Bis-Silane (p=0.01), with similar results for the two latter. Warm air-drying and laser treatment significantly increased PBS (p<0.001). The lowest and highest PBS was obtained in the control (no silane) group (190.9±31) and laser-treated/ Porcelain Primer group (377.1±50), respectively.ConclusionsWarm air-drying and CO2 laser heat treatment had a significantly beneficial effect on retentive strength of fiber posts. Porcelain Primer was significantly more effective than universal adhesive and Bis-Silane. Key words:Laser heat treatment, Pull-out bond strength, fiber post.
Background The present study aimed to investigate the effect of bacterial cellulose nanocrystals (BCNC) on the shear bond strength (SBS) of resin modified glass ionomer cement (RMGIC) to dentin. Material and Methods A total of 48 freshly extracted intact third molars were randomly divided into four main groups with three different concentrations (0.3%, 0.5% and 1% wt) of BCNC with RMGIC and control group without BCNC. These specimens were kept in distilled water at 37° C for 24h. Shear bond strength was examined, using the universal testing machine. Kruskal-Wallis test and Dunn`s post-hoc test were applied for analysis of data. P <0.05 was considered as the level of significance. Results The addition of a 1%wt of BCNC to the RMGIC led to a significant increase in the shear bond strength (7.17 ± 2.14) compared to the control group (2.09 ± 1.80) ( P =0.007). The shear bond strength was improved up to 343%. Conclusions It was found that the incorporation of 1% wt BCNC to the RMGICs enhanced the SBS properties of the RMGIC significantly. Modifying RMGIC with BCNC might be advantageous in terms of improving the restorative material. Key words: Bacterial cellulose nanocrystals, RMGIC, Shear bond strength.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.