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Objective: To evaluate the whiteness index (WID) and surface roughness (Ra) of bovine enamel after simulated tooth brushing with different commercial and experimental whitening dentifrices. Materials and Methods: Cylindrical enamel bovine specimens were acid etched, stained, and divided in nine groups (n = 8): Colgate® Optic White®, Crest® Baking Soda and Peroxide, Arm and Hammer® Advanced White™ Extreme Whitening, Rembrandt® Deeply White® + Peroxide, Close up® White Attraction Natural Glow, Hinode Prowhite, and experimental dentifrice containing papain (PP), bromelain (PB), or papain and bromelain (PPB). Ra and WID were obtained initially and after 600, 1200, and 3,600 cycles of simulated tooth brushing. Data were analyzed using two‐way analysis of variance test (α = 0.05). Results: Ra was significantly influenced by both dentifrice (p = 0.043) and period of tooth‐brushing simulation (p < 0.001). Except for PP and PPB, all groups showed a statistically significant increase in Ra after simulated tooth brushing. After staining and brushing, none of the materials tested increased the initial WID. Conclusions: The effect of commercial whitening dentifrices may be related to their high abrasiveness. Experimental formulations tested provided a similar effect without undesired wear of enamel. Whitening dentifrices only act through an abrasive effect rather than bleaching the tooth structures. When used, special care must be taken for avoid undesired wear of enamel. Experimental dentifrices provided similar removal of extrinsic stains without undesired abrasiveness; however, this effect may be due to the use of less aggressive abrasives in their formulations. [ABSTRACT FROM AUTHOR]

The effect of the addition of nystatin and an alternative antifungal derived from pyrazoles in different commercial denture adhesives on their retentive efficacy, cytotoxicity and antimicrobial activity against Candida albicans was evaluated. Commercial denture adhesives were prepared with the inclusion of nystatin and 3,5-diaryl-4,5-dihydro-1H-pyrazole-1-carboximidamide (pyrazole) in three concentrations: 23.78 %w/w, 3.02 %w/w, and 0.31 %w/w (0.015 g, 0.0015 g, and 0.00015 g, respectively). The retentive efficacy was tested observing the influence of the medium, type of commercial denture type and the test condition (dipping). The antifungal action through disk diffusion and direct contact tests at 1, 4, 8 and 12 h and cytotoxic activity was evaluated in mouse fibroblasts (NIH/3T3) by the MTT reduction colorimetric assay. The addition of pyrazole and nystatin in commercial denture adhesives did not affect retentive efficacy rates and enhanced antifungal actions against Candida albicans. Results show a possibility of using denture adhesives as a delivery system for commercial antifungals (Nystatin) or pyrazole, with the second concentration (1,560 µg–3.02 %w/w) as the most efficient. [ABSTRACT FROM AUTHOR]

Introduction: A systematic review and meta-analysis were conducted to evaluate the physicomechanical properties of tertiary monoblock obturation with different obturation techniques. Methods and Materials: PubMed (MEDLINE), Web of Science, Scopus, the Cochrane Library, LILACS, IBECS, and BBO were searched time. PICO question was: "In extracted human teeth (Population), does tertiary monoblock obturation (Intervention) have superior physicomechanical properties (Outcome) compared to conventional obturation systems (Comparison)?". Statistical analyses for push-out bond strength were performed with RevMan software by comparing the mean differences of each study, with a 95% confidence interval. Inverse variance was used as statistical method, random-effects models as analysis model, and heterogeneity between studies was assessed by Cochran's Q test and I² statistic (P<0.05). Results: Of 2162 studies retrieved, 31 were included in this review for "Study Characteristics". Ten studies were included in the meta-analysis. Analysis demonstrated that conventional obturation had significantly higher push-out bond strength than tertiary monoblock obturation (P<0.01), with a mean difference of-1.00 (95% CI, -1.41 to -0.58; I²=100%). Subgroups using single-cone and cold lateral condensation techniques showed significantly lower push-out bond strength for tertiary monoblock obturation (P<0.01), respectively with a mean difference of-0.09 (95% CI, -1.13 to -0.67; I²=97%) and of-1.97 (95% CI, -3.19 to -0.75; I²=100%). The warm vertical compaction subgroup showed no statistically significant difference between tertiary monoblock and conventional systems (P=0.13), with a mean difference of 0.49 (95% CI, -0.14 to 1.12; I²=10%). Conclusion: Tertiary monoblock systems have a push-out bond strength similar'to conventional [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the mechanical and physical properties of experimental HEMA-containing and HEMA-free resin adhesives. Materials and Methods: Experimental HEMA-free adhesives containing alternative dimethacrylates (bis-EMA 10 [B10], bis-EMA 30 [B30], PEG 400 [P400], PEG 1000 [P1000], PEG 400 UDMA [UP400]) were formulated and compared with a HEMA-containing adhesive (control). The adhesives were characterized by rheological analysis, polymerization kinetics (PK), water sorption (WS), and solubility (SL) tests. Flexural strength (FS) and flexural modulus (E) tests were performed under dry or wet conditions (distilled water or 70% ethanol solution). One-way and two-way ANOVA as well as Tukey's test were used to evaluate differences between groups (p < 0.05). Results: The control group showed the lowest viscosity and was the only one with a degree of conversion lower than 50%. The control and the P1000 adhesive showed the statistically significantly highest WS (p < 0.05). The control and the UP400 adhesive showed the highest FS and E, and the dry-stored specimens showed more improved mechanical strength than did the wet-stored specimens (p < 0.05). Conclusion: The physicomechanical properties of some of the HEMA-free adhesives were substantially improved when compared with those of the control, indicating that they could be potential monomers for the development of HEMA-free adhesive systems. [ABSTRACT FROM AUTHOR]

Objective: Dentin desensitizing agents are used in the treatment of dentin hypersensitivity, which is defined as a painful response in the exposed dentin to stimuli that are thermal, evaporative, tactile, osmotic, or chemical. A systematic review was conducted to analyze the clinical effectiveness of current desensitizer with at least 3 months of follow-up. Method and Materials: Eight electronic databases were searched: MedLine (PubMed), Embase, Lilacs, Ibecs, Web of Science, Scopus, Scielo, and The Cochrane Library. Only those clinical trials published from 2000 to 2012 were included. Results: A total of 3,029 relevant records were identified. After title and abstract examination, 2,645 articles were excluded. A data extraction form was designed and completed by reviewers from the selected studies for a retrospective comparison. From the 99 studies retrieved for detailed review, only 17 had an evaluation time of at least 3-months follow-up and fulfilled the selection criteria. Conclusion: Cervitec Plus, SE Bond & Protect Liner F, laser, and iontophoresis have shown satisfactory posttreatment results between 3 and 6 months. However, additional clinical trials are warranted to better compare the different types of treatments and their effectiveness in the longer term. [ABSTRACT FROM AUTHOR]

The aim of this study is to analyze the efficacy of natural bleaching agents and the current technological development in this research field. Two reviewers performed a literature search up to July 2019 in 15 databases. Five laboratory studies and 25 patents were included. Data regarding natural bleaching agent used, application protocol, and the main findings of studies were analyzed. Laboratory studies that evaluated natural bleaching agents' peroxide-free or associated to peroxides and patents related to natural bleaching agents were included. The studies evaluated papain, bromelain, chlorine dioxide, sodium chloride plus vinegar and sodium bicarbonate as peroxide-free agents; and sweet potato extract, lactoperoxidase, and peroxidase associated to peroxide used were included. Twenty-five patents were included; among the most cited are the papain and the chlorine. The addition of non-peroxide agents into peroxide showed improvement in bleaching effect with the incorporation of these non-peroxide agents (p < .05). On the other hand, peroxide-free agents did not show an improvement in bleaching effect (p < .05). The evidence in literature suggested that natural bleaching agents incorporated to peroxide may improve the bleaching. Therefore, the current literature does not support the use of natural agents as dental bleaching. [ABSTRACT FROM AUTHOR]

This study aimed to investigate the one-year bond strengths to dentin of one-bottle etch-and-rinse adhesive systems applied under different moisture conditions. Class V cavities were prepared in bovine incisors and randomly allocated (n = 8) according to the type of adhesive system used – SB (Adper™ Single Bond 2); PB (Prime & Bond 2.1); and XPB (XP Bond) – and the moisture condition kept in the cavity – moist, over-wet, and over-dry. Filtek™ Z250 was used for teeth restoration. Specimens for microtensile bond strength (µTBS) test were obtained and stored in water for 24 h or 1 year, and submitted to mechanical testing. Data were analyzed using t-tests, ANOVA and the Holm–Sidak post hoc test (α = 0.05). Weibull analysis was used to verify the reliability of specimens. The type of adhesive and the moisture condition of the substrate affected the µTBS. At 24 h, SB performed better under the moist and over-wet conditions. At 1 year, SB, PB, and XPB showed the greatest percentage reduction at the moist (∼38%), over-wet (100%), and over-dry (100%) conditions, respectively. The reliability of adhesives was affected by the variable factors tested. In conclusion, the solvent composition of adhesives and the moisture condition of the substrate play an important role in the bond strength and bonding stability of resin-based restorations, as well as on the reliability of the adhesive interfaces over time. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluated the resin-dentin microtensile bond strength (μTBS) of ethanol/water- (Single Bond, [SB] 3M ESPE), ethanol- (Optibond Solo Plus, [OP] Kerr) and acetone-based (One-Step, [OS] Bisco) two-step etch-and-rinse adhesives in the presence or absence of their respective solvents to dry and wet dentin. The ultimate tensile strength (UTS) and the degree of conversion (DC) of the materials were also evaluated. Materials and Methods: Solvent-based and solvent-free adhesives were vigorously applied to occlusal dentin surfaces after phosphoric acid etching. Composite crowns were built up incrementally. After 24-h water storage, the specimens were sectioned in x and y directions to obtain bonded sticks (1.0 mm²) which were immediately tested in tension (0.5 mm/min). The data were analyzed by three-way ANOVA and Tukey's test (α = 0.05). For the UTS measurement, hourglass-shaped specimens of adhesives were prepared and tested in tension. FTIR analysis was used to verify the DC of adhesives. The data from UTS and FTIR was analyzed by two-way ANOVA and Tukey's test (α = 0.05). Results: High μTBS values were obtained for SB and OS, regardless of the presence or absence of solvents or the moisture condition of dentin. A lower μTBS mean was observed for the solvent-free OP compared to its solvent-based version. Significantly higher UTS values were obtained for all adhesives after removal of solvents. The DC of OS in the solvent-based condition was lower than SB and OP. After removal of solvents, only OS showed a significant increase in the DC. Conclusion: The presence of solvents was not essential for SB and OS to achieve high bond strength values to both dry and wet dentin when applied under vigorous application. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the solubility and the fluoride release of different materials used for orthodontic band cementation in different solutions and at different times.Materials and Methods: Three materials were selected: Ultra Band-Lok (UBL); RelyX (RLX) and Ketac-Cem (KTC). Sixteen standard samples from each material were prepared, according to the manufacturers' instructions. The samples were stored in two different solutions (n = 8): 0.9% saline solution (pH 7.0) and 0.1 mol/l lactic acid (pH 4.0). The storage solutions were changed after 24 h and after 7, 15 and 30 days. The fluoride release was determined with an ion-specific electrode (Analion). For the solubility evaluation, the formula Wsl = (m1-m2)/V was used to determine the loss of mass. Data were submitted for statistical analysis using the non-parametric Kruskal-Wallis test.Results: With respect to the solubility, immersion in lactic acid increased the solubility when compared with saline solution (P < 0.01). In both the solutions, there were differences among materials (P < 0.01) with the following rankings: UBL < RLX < KTC for lactic acid and UBL < RLX < KTC for saline solution. The ranking of fluoride release was UBL < KTC < RLX. In the two tested solutions, RLX exhibited the highest fluoride release (P < 0.01), whereas KTC showed more fluoride release than that of UBL (P < 0.05). Fluoride release decreased over time and the storage solution influenced the fluoride-releasing capacity of some materials.Conclusions: It was found that fluoride release was influenced by storage solution, materials and immersion time. Materials and storage solution were the significant factors for solubility. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the influence of different water concentrations in the solvents of self-etching primers on microtensile bond strength (μTBS) of an experimental adhesive system. Materials and Methods: Five experimental self-etching primers with 0, 5, 10, 20 and 40 (wt%) water as solvent were formulated. An experimental adhesive resin (AD-50) was also synthesized to create one experimental self-etching adhesive system. Clearfil SE Bond (CSEB) was used as the commercial reference. Sixty bovine incisors were randomly separated into 6 groups. Buccal enamel was removed to expose the superficial coronal dentin; this surface was polished wet to create a standardized smear layer. After rinsing, water was removed, leaving the surface visibly dried. The dentin surfaces were etched with primer and air dried, adhesive resin was applied and photoactivated, then the composite resin restoration was placed. After storage for 24 h, the specimens were sectioned with a cooled diamond saw at low speed. Microtensile bond strength was measured and data were analyzed with one-way ANOVA/Tukey's test (α = 0.05). Results: ANOVA showed that primer composition was a significant factor for bond strength. There was no significant difference in bond strengths between the primers with a water concentration of 40% (53.9 ± 12.7 MPa), 20% (51.1 ± 11.5 MPa, and 10% (47.5 ± 11.4 MPa), and CSEB (50.7 ± 9.8 MPa). The groups with 5% (38.6 ± 12.9 MPa) and 0% (31.5 ± 7.5 MPa) water presented similar bond strengths amongst themselves but were statistically significantly lower than that of the other groups. Conclusion: The water concentration in the primer solvent exercises a significant influence on the bond strength of this experimental self-etching adhesive system. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the pulp response to direct capping with self-etching adhesive systems using sodium hypochlorite as a hemostatic agent. Method and Materials: Twenty-six human third molars scheduled for extraction were selected from undergraduate students of dentistry. Class I cavities with pulp exposures were performed. To control bleeding, 2.5% sodium hypochlorite was used for 20 seconds, followed by washing with saline solution. The pulp exposures were capped with calcium hydroxide (n = 10) or adhesive system (n = 16). All cavities were restored with adhesive system and composite resin. Half of the samples of each capping material were extracted after 30 days and the remaining after 90 days. The samples were prepared for histological analysis (hematoxylin-eosin) and bacterial detection (Brown & Hopps) and evaluated according to standard ranking. Data were submitted to statistical analysis (Mann-Whitney test). Results: There was a significant difference (P < .05) only in relation to dentin barrier formation. Pulps dressed with calcium hydroxide showed dentin barrier formation in all specimens, obliterating the exposure site. No inflammatory response was associated with material. In the experimental group, after 30 days, there was an attempt for healing with reparative dentin deposition, presenting a mild to moderate inflammatory infiltrate. Similar findings were found after 90 days, decreasing the inflammatory response. Bacteria were not detected in any specimen evaluated. Sodium hypochlorite was effective for hemostatic control. Conclusion: Calcium hydroxide produced better biological performance than the self-etching adhesive, and sodium hypochlorite did not interfere with the pulp repair. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the clinical performance of two polyacid-modified resin composites (Dyract AP and F2000) in posterior teeth after 1 year of clinical service. Materials and Methods: Seventy-two Class I restorations were performed in 33 patients (average age 25 years) by one operator. Eighty-two per cent of the restorations were located in molars. Before the proceedings, patients were informed about the aim of the study and they gave written consent to participate. At least one restoration of each material was placed in each individual. The materials were applied according manufacturer's instructions. Following finishing and polishing, one examiner performed the clinical baseline examination using the adapted USPHS system. To be included in the clinical trial, a restoration had to be rated "Alpha". After one year, 25 patients were recalled and 56 restorations were evaluated using the adapted USPHS system. Results: All restorations were classified as clinically satisfactory (Alpha or Bravo). However, there was a decrease in restoration quality compared to baseline. Statistical analysis (X² and Fisher's exact test) demonstrated differences only in relation to superficial roughness, with exhibiting F2000 more surface roughness than Dyract AP (p < 0.01). Conclusion: Based on the methodology employed, all restorations were satisfactory after one year and the two materials performed similarly, except for the surface roughness criteria. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluated the effect of blood contamination and decontamination procedures performed at different stages of bonding, on the microtensile bond strength (µTBS) of an etch-and-rinse adhesive to dentin. Materials and Methods: Standardized cylindrical cavities were prepared in bovine incisors and were randomly divided into five groups, each one was treated using these experimental conditions - Control: etching-rinsing/bonding without blood contamination; Group 1: etching-rising/blood contamination/decontamination/bonding; Group 2: etching-rising/bonding/blood contamination/decontamination; Group 3: etching-rising/bonding/blood contamination/decontamination/etching-rising/bonding; and Group 4: etching-rising/blood contamination/decontamination/etching-rising/bonding. Specimens were prepared for µTBS and were evaluated both immediately and after 6 months of storage in distilled water. Results: Blood contamination significantly reduced the µTBS (P < 0.001). Groups 2 and 3 showed the lowest µTBS values, both for 24 h and 6 month aging. Conclusions: Blood contamination tested at any of the different stages of the bonding procedure showed a negative effect on the µTBS. Recovering adhesion of blood-contaminated dentin did not depend only on cleaning with distilled water. [ABSTRACT FROM AUTHOR]

Introduction: This in vitro study aimed to evaluate the chemical composition, water solubility, radiopacity, pH, electrical conductivity and cytotoxicity of four different root canal sealers. Methods and Materials: Four materials were tested including an epoxy resin-based sealer (AH-Plus), a calcium silicate-based sealer (MTA Fillapex), a calcium hydroxide-based sealer (Sealapex) and a zinc-oxide-eugenol-based sealer (Endofill). The materials were submitted to energy-dispersive x-ray microanalysis for elemental chemical composition. Solubility and radiopacity were evaluated according to ANSI/ADA. The pH and electrical conductivity were measured at different periods of time. L929 immortalized mouse fibroblast line were used for cytotoxicity evaluation. Statistical analyses were carried out using the ANOVA and Tukey's test. Results: The main elements were found to be silicon and calcium in MTA Fillapex, calcium and bismuth in Sealapex, zirconium and tungsten in AH-Plus and zinc and bismuth in Endofill. Sealapex had the highest value for solubility (P<0.05), AH-Plus showed the highest radiopacity value (P<0.05) while MTA Fillapex had the highest pH and electrical conductivity values (P<0.05). AH-Plus showed the highest rate of cell viability (P<0.05). Conclusion: Based on the results of this in vitro study, it was possible to conclude that Endofill and Sealpex did not meet the requirements for water solubility. The tested sealers were alkaline and showed radiopacity in accordance with ANSI/ADA standards. AH-Plus showed to be less cytotoxic than other tested [ABSTRACT FROM AUTHOR]