RESUMEN
Background: Cavity preparation often causes gingival bleeding which can be controlled by hemostatic agents (HAs). These along with blood act as contaminants and hamper the bonding mechanism. Collagen cross-linkers (CCLs) are agents known to increase the bond strength (BS) to dentin. Hence, the purpose of this in vitro study was to determine the effect of two different CCLs, proanthocyanidin (grape seed extract [GSE]) and hesperidin on the microtensile BS (µTBS) of a self-etch adhesive (SEA) system to dentin which was contaminated with blood and a HA. Materials and Methods: Thirty-six extracted human molars were collected, and their occlusal surfaces were sectioned to expose the dentin. The teeth were randomly divided into four groups: Group I - Control, Group II - Contamination with blood and HA, Group III - Application of GSE after contamination, and Group IV - Application of hesperidin extract after contamination. The SEA was applied, followed by the use of a nanocomposite. Dentin-composite rods were obtained from each group, and µTBS testing was done. The fracture pattern was visually classified as an adhesive failure at the interface, cohesive failure in composite, or dentin. The scanning electron microscope (SEM) analysis was done for two samples from each group. Statistical analysis was done using the Student's unpaired "t" and ANOVA test. Results: Group II showed a statistically significant reduction in µTBS in comparison to Group I. This was overcome in Groups III and IV. Hesperidin showed marginally better results than GSE. Conclusions: The use of GSE and hesperidin increases the µTBS of composite resin to dentin postcontamination with blood and ViscoStat Clear with Single Bond Universal Adhesive.
RESUMEN
The essential factor in determining the preservation of restoration is the marginal seal. Restoring cervical lesions with a resin composite has always been a challenge. Composite resins with various viscosities and different bonding systems are being researched to reduce the microleakage. Confocal laser scanning microscopy (CLSM) is the latest non-destructive technique for visualizing the microleakage. Objectives: To evaluate and compare the microleakage of Universal Flo composite resin (G-aenial) using etch and rinse adhesive system ER-2 steps (Adper Single Bond 2), self-etch adhesive system SE-1 step (G-Bond), and self-adhesive flowable composite resin (Constic) in Class V cavities using a confocal laser scanning microscope. Materials and Method: Class V cavities were prepared on 27 caries-free human extracted premolar teeth on the buccal and lingual surfaces with standardized dimensions of 2 mm height, width 4 mm, and a depth of 2 mm. After the cavity preparation, all teeth were randomly divided into three groups, namely Group-I: G-aenial Universal Flo with Single Bond 2 (n = 9 teeth); Group-II: G- aenial Universal Flo with G-Bond (n = 9 teeth), and Group-III: Constic (n = 9 teeth). The prepared and restored specimens were then subjected to thermocycling for 500 cycles in a water bath at 5 °C and 55 °C with a dwelling time of 30 s. The specimens were placed in 0.6% aqueous rhodamine dye for 48 h. Sectioning was carried out bucco-lingually and specimens were evaluated for microleakage under a confocal laser scanning microscope. Results: There was a significant difference (p = 0.009) in microleakage when comparing total etch and rinse, specifically between Adper Single Bond 2 ER-2 steps (fifth generation) and self-adhesive flowable composite resin, which is Constic. There was more microleakage in the self-etch bonding agent, particularly G-Bond, SE-1 step (seventh generation), when compared to ER-2 steps (fifth generation bonding agent); however, the results were not statistically significant (p = 0.468). The self-adhesive flowable composite resin showed more microleakage than SE-1 step and ER-2 steps. Conclusions: None of the adhesive systems tested were free from microleakage. However, less microleakage was observed in the total etch and rinse, especially Adper Single Bond 2 (ER-2 steps), than the self-etch adhesive system SE-1 step and self-adhesive flowable composite resin. Clinical significance: Constant research and technological advancements are taking place in dentin adhesives to improve the marginal seal. This has led to the evolution of total acid-etching dentin bonding agents termed as etch and rinse (ER)-2 steps (fifth generation dentin bonding agents) and self-etching (SE) 2 steps, and SE-1 step dentin bonding agents termed as the sixth and seventh generation bonding agents, respectively.
RESUMEN
The success of the sandwich technique depends on the bond strength of composite to glass-ionomer cement (GIC)/resin-modified glass-ionomer cement (RMGIC). Currently used adhesives employ the total-etch and the self-etch techniques. The total-etch system is technique sensitive, whereas the self-etch system is popular for its ease of use. The aim of this systematic review is to compare the effect of total-etch and self-etch adhesives (SEAs) on the bond strength of composite to GIC/(RMGIC) in the sandwich technique. A literature search was conducted using electronic databases (PubMed, Web of Science, Ebscohost, and Scopus) limiting the year of publications from January 1, 2000, to September 30, 2018, to identify the relevant studies. All the cross-references of the selected studies were also screened. In vitro studies on extracted human teeth were selected. A total of 10 articles were included in this review. A conclusion was drawn that SEAs when used in the sandwich technique resulted in greater bond strength in comparison to total-etch adhesives. Moreover, increased bond strength was achieved when the primer was employed on unset GIC as compared to set GIC. Furthermore, the application of SEAs over uncured RMGIC (co-curing technique) resulted in better bond strengths as compared to their application over cured RMGIC.
RESUMEN
AIMS: The aim of the study was to evaluate the effect of 10% sodium ascorbate (SA),10% hesperidin, 1% riboflavin 5-phosphate, collagen cross-linkers, on the pushout bond strength of the fiber resin postluted to the radicular dentin. MATERIALS AND METHODS: Twenty-eight, single-rooted extracted human teeth were collected. The cleaning shaping and obturation was done followed postspace preparation which was etched with 37% phosphoric acid for 15 s and then rinsed with normal saline. The specimens were divided into four groups and postspaces were irrigated, respectively with. (i) Group 1: Normal saline for 4 min, (ii) Group 2: 10% SA for 4 min, (iii) Group 3: 10% hesperidin for 4 min, and (iv) Group 4: 1% riboflavin 5 phosphate (RFV) for 4 min. The pushout bond strength of fiber postluted to root dentin, of all the above groups, was compared. Posts were luted using Rely X Arc luting cement. Each root was horizontally sectioned to obtain 2 mm thick, 28 dentinal disks, per group. The pushout bond strength test was carried out using Universal Testing Machine. The scores were statistically analyzed using Student's Unpaired "t" and ANOVA test. RESULTS: Comparison of different collagen crosslinker showed that the highest pushout bond strength value was recorded with 10% hesperidin, followed by 1% RFV and 10% SA. CONCLUSION: All collagen cross-linkers so used, increased the bond strength. The highest push-out bond strength was achieved with 10% hesperidin.
