Does post-bleaching fluoridation affect the further demineralization of bleached enamel? An in vitro study

WOS: 000341394700001PubMed ID: 25193250Background: Topical fluoride agents have been shown to be the most effective method in treating demineralized enamel after in-office bleaching treatments. Thus, this study aimed to examine the effects of two different post-bleaching fluoridation agents: 1.5% titanium tetrafluoride (TiF4) (9200 ppm) and 2.1% sodium fluoride (NaF) (9500 ppm), on the calcium loss of enamel after an acidic challenge. Methods: Ten maxillary premolars were sectioned into four pieces and then divided into the following four groups: Group 1: Control, kept in artificial saliva, no treatment; Group 2: 38% hydrogen peroxide (HP); Group 3: 38% HP followed by 1.5% TiF4; Group 4: 38% HP followed by 2.1% NaF solution. The specimens were subjected to demineralization for 16 days, refreshing the solution every 4 days; that is, on the 4th, 8th, 12th, and 16th days. Calcium ion (Ca2+) concentration was determined by an atomic absorption spectrophotometer. Data were analyzed using Friedman and Wilcoxon tests (p = 0.05). Results: The loss of Ca2+ in each of the test groups was compared with that of the control group, depicting that there was a statistically significant difference among the groups after 4, 8, 12, and 16 days and in total (p < 0.05). The calcium released from the fluoride-applied groups was lower when compared with the 38% HP and control group. At the end of the 16th day, the total amount of calcium released from the TiF4-treated samples (9.12 mg/mL) was less than from the NaF-treated samples (13.67 mg/mL) (p < 0.05). Conclusions: Regarding the results of our in vitro study, the risk of further demineralization was significantly reduced with the use of TiF4 and NaF after bleaching with 38% HP. TiF(4)was found to be more effective in preventing Ca2+ release owing to acid attack when compared with NaF. In the case of an intra-oral acidic exposure, the use of topical 1.5% TiF4 and 2.1% NaF agents might be beneficial after bleaching with 38% HP

Comparison between translucencies of anterior resin composites and natural dental tissues

Turkun, L. Sebnem/0000-0003-1406-7110WOS:000621871500001We aimed to assess the translucencies of seven anterior resin composites in comparison to natural dental tissues under dry and hydrated conditions. Seven resin composites-Clearfil Majesty ES-2 (A1-AE1), Essentia (LE-Universal), Ceram-X Duo (E1), Synergy D6 Enamel (Universal White Opaque), Harmonize (A1), Filtek Ultimate (XW Enamel), and Zenit (W2)-were used. Five disc-shaped (5 x 1 mm) specimens of each shade were fabricated, and enamel and dentin slices were obtained from extracted teeth. The color coordinates of dry and hydrated samples were measured using the SpectroShade Micro device. Translucency parameter (TP) values were calculated using a formula derivated from the Commission Internationale de l'Eclairage coordinates. Two-way analysis of variance (ANOVA) was used to assess the interaction between the substrate and the storage medium. One-way ANOVA and Tukey tests were used to compare the TP values, and the t test was used to compare the translucency parameter values of dry and hydrated samples (P < .05). Translucency parameter values of all dry and hydrated resin composites were higher than those of enamel and dentin samples (P < .05) except for Clearfil Majesty ES-2 A1 and Ceram-X Duo E1. Hydration increased the translucency parameter value of all samples (P < .05) except Ceram-X Duo E1, Harmonize A1, and Filtek Ultimate XW shades where the values were unchanged. Translucency seems to be material-specific, and no generalization relating to the different substance classes could be made. Hydration and type of materials had a significant effect on TP values. Furthermore, translucency parameter values of anterior resin composites were higher than those of dental tissues, different from each other, and increasing or remain unchanged with hydration depending on the brands tested

Tensile Bond Strength of an Aged Resin Composite Repaired with Different Protocols

WOS: 000294079200008PubMed ID: 20978641Purpose: To evaluate the effect of different surface treatments and bonding procedures on the tensile bond strength (TBS) of resin composites repaired 6 months after polymerization. Materials and Methods: Resin composite sticks were aged in distilled water at 37 C for 6 months. They were divided into 12 groups (n = 10) according to the combination of surface treatment/bonding procedures [none, only bur treatment, XP Bond (XPB/Dentsply/DeTrey) with/without bur, AdheSE (A-SE/Ivoclar/Vivadent) with/without bur, Composite Primer (CP/GC) with/without bur, CP after bur and acid-etching, XPB after acid etching and CP with bur, A-SE after bur and CP]. The ultimate tensile bond strength (UTS) of the resin composites was tested in intact but aged specimens. Tensile bond strengths were tested with a universal testing machine (Shimadzu). Data were analyzed using one-way ANOVA and Duncan Multiple Comparisons tests (p < 0.05). Results: All repaired groups showed significantly higher TBS than the group without any surface treatment (p < 0.05). Four groups resulted in TBS similar to those of intact resin composite UTS: A-SE, A-SE with bur, A-SE after CP with bur, and XPB after acid etching+CP with bur. Conclusion: Bur treatment, silane primer or etch-and-rinse adhesive application alone were not successful in the repair process of aged resin composite, whereas self-etching adhesive alone showed similar performance to the intact specimens. Combined procedures generally showed better performance: A-SE with bur, A-SE after CP with bur, and XPB after acid etching +CP with bur showed TBS similar to those of the intact specimens. It was concluded that bur roughening of the surfaces and rebonding procedures were essential for repairing aged resin composites

The Use of Toothpastes Containing Different Formulations of Fluoride and Bioglass on Bleached Enamel

Objectives: To investigate the application of toothpaste either containing calcium sodium phospho-silicate bioglass (NovaMin) or calcium fluorosilicate bioglass (BioMinF) on the surface mineral composition and morphology of enamel after bleaching procedure. Methods: Thirty extracted noncarious human teeth were allocated into five groups (n = 6). Group 1: Bleaching using 40% hydrogen peroxide (HP) and fluoridated toothpaste containing bioactive glass (1450 ppm fluoride). Group 2: Bleaching using 40%HP and toothpaste containing calcium fluorosilicate bioglass (540 ppm fluoride). Group 3: Bleaching using 40%HP and fluoridated toothpaste (1450 ppm fluoride). Group 4: Bleaching alone using 40%HP. Group 5: Negative control with distilled water alone. The surface morphology was evaluated using Scanning Electron Microscope (SEM) and Scanning Probe Microscope (SPM). The concentration of elements as atomic percentages were determined by X-ray Photoelectron Spectroscopy (XPS) and Energy-Dispersive X-ray Spectroscopy (EDS). Results: This laboratory-based study reported that SPM and SEM detected minor changes on the surfaces of all toothpaste-treated enamel samples (Groups 1–3) after 45 days. Bioactive glass deposits were observed on enamel surfaces in Groups 1 and 2, whilst the bleaching-alone samples (Group 4) had rough enamel surfaces. XPS reported that toothpaste containing calcium fluorosilicate bioglass (Group 2) had a high atomic% of calcium and phosphate, whilst silicon values were high in the toothpaste containing bioactive glass and 1450 ppm fluoride (Group 1) after bleaching procedure when compared to other groups (p Conclusions: Within the limitations of this laboratory-based study, there was no significant decrease in the Ca%, P% values and surface properties of enamel after the bleaching procedure following the use of different formulations of toothpastes for a period of 45 days. However, the Ca% and P% values were significantly high for the toothpaste containing calcium fluorosilicate bioglass (BioMinF) on the bleached enamel. Clinical relevance: The bleaching process can provide optimum aesthetic outcomes, but the effect of peroxides on hard tissues is still in question. Toothpastes containing different formulations of fluoride and bioactive glass might have the potential to prevent mineral loss on bleached enamel. However, further laboratory-based studies and controlled double-blind randomised clinical trials are required to interpret the effects of toothpastes with different fluoride and bioactive glass formulations on enamel surfaces following bleaching procedures

The improvement of biocompatibility of adhesives: The effects of resveratrol on biocompatibility and dentin micro-tensile bond strengths of self-etch adhesives

WOS: 000474396700008PubMed ID: 30415440ObjectiveThe aim of this in vitro study is to evaluate the effects of resveratrol (RES) addition on the cytotoxicity and microtensile bond strength (mu TBS) of different adhesives.Materials and methodsFive self-etching adhesives (G-aenial Bond-GC, Optibond All in One-Kerr, Gluma Self Etch-Kulzer, Clearfil S-3 Bond-Kuraray, and Nova Compo-B Plus-Imicryl) were tested. They were applied to L-929 cell culture by the extract method. In the test groups, 0.5 mu M RES (Sigma-Aldrich) was added into the medium. Cell viability was assessed by MTT assay after 24h. Human extracted third molars were used for mu TBS test (n=7). The adhesives with or without 0.5 mu M RES addition were applied on dentin surfaces. A composite build-up was constructed. Then, the specimens were sectioned into multiple beams with the non-trimming version of the microtensile test and subjected to microtensile forces. Statistical analysis was performed using ANOVA and post hoc Tukey test (p?0.05).ResultsThe extracts of all adhesives decreased the cell viability. However, RES addition increased the cell viability in all groups (p?0.05). RES addition did not cause any decrease in mu TBS values of the adhesives compared to baseline. Optibond All in One showed the highest mu TBS after RES addition. It was followed by Clerafil S-3 Bond and Nova Compo-B Plus. No difference was determined between the Optibond All in One and Clearfil S-3 Bond. There was difference between Optibond All in One and Nova Compo-B Plus (p?0.05).ConclusionRES addition may improve the biocompatibility without causing negative influence on mu TBS of the adhesives.Clinical relevanceRES addition has clinical applicable potential to overcome the adverse biocompatibility of adhesives