sodium-hypochlorite and ferric-chloride

The aim of the current study was to compare the bond strength of an experimental bonding system with commercial bonding systems.. An aqueous solution of 10% ascorbic acid and 5% ferric chloride was prepared as an experimental conditioner (Exp). The flattened human dentin surfaces were conditioned with phosphoric acid, NaOCl, and Exp. They were bonded to a stainless steel rod with 4-META/MMA-TBB resin. Super-Bond C&B (10-3), Panavia Fluoro Cement (Panavia), Panavia Fluoro Cement with AD gel (AD/Panavia), and All-Bond 2 system (All-Bond 2) were also used. After immersion in water for 24 h, half of the specimens of each group were tested for tensile bond strength, and the remaining specimen groups were subjected to 10,000 cycles of thermo-cycling prior to tensile testing. All of the data were analysed by ANOVA and a post hoc test. In addition, two thermo-cycled specimens (10-3/10,000, Exp/10,000) were prepared for photomicrography.. The bond strengths of Exp and AD/Panavia groups showed no decrease after 10,000 thermo-cycles, although those of 10-3, Panavia, and All-Bond groups decreased significantly after thermo-cycling. SEM micrographs exhibited that cracks and voids can be observed in the 10-3/10,000 specimen at the interface of the adhesive resin and the hybrid layer, although neither a hybrid layer nor cracks can be seen in the Exp/10,000 specimen.. Comparison of the tensile bond strengths for all adhesive resins revealed that the novel dentin bond system with experimental conditioner and Panavia Fluoro Cement with AD gel exhibited the most durable bonding after thermo-cycling.

Topics: Acid Etching, Dental; Analysis of Variance; Ascorbic Acid; Boron Compounds; Chlorides; Dental Bonding; Dentin; Dentin-Bonding Agents; Ferric Compounds; Humans; Materials Testing; Methacrylates; Methylmethacrylates; Phosphoric Acids; Resin Cements; Sodium Hypochlorite; Stainless Steel; Surface Properties; Tensile Strength

Methylated arsenic can be found in virtually all earth surface environments. So far, however, little information has been collected regarding their removal by coagulation. In this study, the removal of monomethylarsenate (MMA) and dimethylarsenate (DMA) from drinking water by coagulation was investigated from the viewpoint of methyl substitution. Results indicated that FeCl3 was more efficient than AlCl3 and polyaluminum chloride (PACl) in methylated As removal. For the initial arsenic concentration of 200 μg/L, an FeCl3 dosage of 0.2 mmol Fe/L was sufficient to attain about 95% removal of MMA, while a dosage of 0.6 mmol Fe/L achieved about 57% removal of DMA. Arsenic removal efficiency was negatively correlated with the degree of methyl substitution. With the increase in methyl group number, the quantity of negatively charged arsenic species decreased and molecular size increased, leading to the decrease of methylated As removal by coagulation. Adsorption on preformed hydroxide flocs was the major mechanism during coagulation. Both FTIR and XPS results indicated that the As−O group of As might substitute the O−H group of Fe/Al hydroxide to form a Fe/Al−O−As complex. Furthermore, the use of traditional oxidants and coagulation aids exhibited limited help for improving coagulation removal of DMA.

Topics: Adsorption; Aluminum Hydroxide; Arsenates; Arsenic; Chlorides; Drinking Water; Ferric Compounds; Methylation; Oxidants; Potassium Permanganate; Sodium Hypochlorite; Water Pollutants, Chemical; Water Purification

An experimental conditioner (Exp), which was an aqueous solution of 10% ascorbic acid and 5% ferric chloride, was prepared in this study. This study evaluated the effect of Exp on the microtensile bond strength between a self-curing resin and dentin after long-term water immersion. Flat human dentin surfaces were sequentially pretreated with 40% phosphoric acid, 10% sodium hypochlorite, and Exp. Surface pretreatment with an aqueous solution of 10% citric and 3% ferric chloride (10-3) was used as a control. Composite resin rods were bonded to pretreated dentin surfaces using 4-META/MMA-TBB resin. Microtensile bond strengths were evaluated after water immersion at 24 h, 12 months, 24 months, and 36 months. At each immersion period, the bond strength of Exp was significantly higher than that of 10-3. After 36 months, Exp showed no significant decrease in microtensile bond strength, but 10-3 showed significant reductions. Pretreatment with experimental acid/base conditioner markedly improved the bonding durability of 4-META/MMA-TBB resin to human dentin when compared against the conventional 10-3 treatment.

Topics: Acid Etching, Dental; Ascorbic Acid; Boron Compounds; Chlorides; Citric Acid; Composite Resins; Dental Bonding; Dental Materials; Dentin; Ferric Compounds; Humans; Hydrogen-Ion Concentration; Immersion; Materials Testing; Methacrylates; Methylmethacrylates; Microscopy, Electron, Scanning; Phosphoric Acids; Resin Cements; Sodium Hypochlorite; Stress, Mechanical; Tensile Strength; Time Factors; Water

It has been reported that the tensile bond strength between the 4-META/MMA-TBB resin and dentin pretreated with 10% citric/3% ferric chloride solution decreased after immersion in water for 2 years. The current study investigated the effect of an experimental dentin conditioner on the bonding of 4-META/MMA-TBB resin to dentin after thermocycling. The experimental conditioner was an aqueous solution of 10% ascorbic acid and 5% ferric chloride (Exp). Human teeth were prepared to expose flat dentin surfaces. These were treated sequentially with 40% phosphoric acid, 10% sodium hypochlorite, and the experimental conditioner. A commercially available dentin conditioner, an aqueous solution of 10% citric/3% ferric chloride (10-3) was used for a control group. Stainless steel rods were bonded to the pretreated dentin surfaces with the use of the 4-META/MMA-TBB resin. Tensile bond strengths were determined after 0, 5,000, 10,000, 20,000 themocycles. All data were analyzed by ANOVA, and differences among groups were analyzed by Duncan's new multiple range test (n = 10, p < 0.05). The experimental group showed no significant decrease in bond strength through 20,000 thermocycles, while the control group exhibited significant decrease after 10,000 thermocycles. Mean bond strength of the experimental groups were significantly higher than those of the control group at both 10,000 and 20,000 thermocycles. A hybrid layer could not be identified in SEM micrographs of the experimental groups. 10-3-conditioned specimen SEMs displayed crack formation between the adhesive resin and a hybrid layer. The experimental dentin pretreatment improved the bond strength of a 4-META/MMA-TBB resin to human dentin compared to 10-3 treatment after thermocycling.

Topics: Acid Etching, Dental; Analysis of Variance; Ascorbic Acid; Biocompatible Materials; Chlorides; Dental Bonding; Dentin; Dentin-Bonding Agents; Ferric Compounds; Hot Temperature; Humans; Materials Testing; Methacrylates; Microscopy, Electron, Scanning; Phosphoric Acids; Resin Cements; Sodium Hypochlorite; Surface Properties; Tensile Strength; Time Factors; Tooth; Water

The purpose of this study was to investigate the efficacy of an experimental dentin primer consisting of ascorbic acid (AA) and ferric chloride (Fe). Three exprimental primers - 10 wt%AA and 0.075 wt%Fe (i.e., 10AA-0.075Fe), 10AA-0Fe, and 0AA-0.075Fe - were prepared. Flattened dentin surfaces were first treated with phosphoric acid and NaClO, and subsequently primed using each experimental solution. Besides the experimental solutions, 10 wt% citric acid and 3 wt% ferric chroride (10CA-3Fe) was also used. A stainless steel rod was bonded to the dentin surface with Super-Bond C&B. 10CA-3Fe/Super-Bond C&B was then used as a control. Tensile bond strengths were evaluated after 24-hour immersion in water. 10AA-0.075Fe showed significantly high bond strength compared to 10AA-0Fe, 0AA-0.075Fe, 0AA-0Fe, and 10CA-3Fe. No significant differences were found between 10AA-0.075Fe and Super-Bond C&B system. The experimental primer consisting of 10 wt% ascorbic acid and 0.075 wt% ferric chloride improved the bonding between Super-Bond C&B and dentin conditioned with phosphoric acid and NaClO.

Topics: Acid Etching, Dental; Acrylic Resins; Analysis of Variance; Ascorbic Acid; Boron Compounds; Chlorides; Dental Bonding; Dental Stress Analysis; Dentin; Dentin-Bonding Agents; Ferric Compounds; Humans; Materials Testing; Methacrylates; Methylmethacrylates; Molar; Phosphoric Acids; Resin Cements; Sodium Hypochlorite; Tensile Strength

The purpose of this study was to evaluate the effect of multi-step conditioning (PA-AD conditioning) with phosphoric acid and sodium hypochlorite on the bond strength of five luting materials to enamel and dentin. Three commercial self-etching/priming systems (Panavia, Linkmax, and Multibond) and two experimental systems (ED/Super-Bond and EDFe/Super-Bond) were used. The surfaces of bovine enamel or dentin were bonded to a stainless steel rod. Tensile bond strength was determined after 24-hour immersion in water. PA-AD conditioning significantly improved the bond strength between enamel and three of the systems (Panavia, ED/Super-Bond, and EDFe/Super-Bond), but did not have any effect on Linkmax and Multibond. Likewise, PA-AD conditioning did not significantly improve the bond strength of Panavia, Linkmax, Multibond, and ED/Super-Bond to dentin. Highest bond strength to dentin (19.7 MPa) was obtained when self-etching primer containing ferric chloride (EDFe/Super-Bond) was used, but additional PA-AD conditioning significantly weakened the bonding (12.6 MPa).

Topics: Analysis of Variance; Animals; Boron Compounds; Cattle; Chlorides; Composite Resins; Dental Bonding; Dental Enamel; Dental Etching; Dental Stress Analysis; Dentin; Dentin-Bonding Agents; Ferric Compounds; Methacrylates; Methylmethacrylates; Phosphoric Acids; Random Allocation; Resin Cements; Sodium Hypochlorite; Tensile Strength

The purpose of this study was to evaluate ascorbic acid (AS) and ferric chloride (FE) for bonding 4-META/MMA-TBB resin to dentin that had been treated with NaClO. An experimental dentin conditioner consisting of 10%AS and 5%Fe (10AS-5FE) and three controls (10AS-0FE, 0AS-5FE, and 0AS-0FE) were prepared. Ascorcic acid neutralizes NaClO. The flattened dentin surfaces were modified sequentially with phosphoric acid etchant, NaClO agent, and the experimental conditioner, then each surface was bonded to a stainless steel rod with 4-META/MMA-TBB resin. The Super-Bond C&B (10-3/SB) system was also used. 24-hour tensile bond strengths were determined. The bonding system using 10AS-5FE conditioner showed significantly high bond strength compared to 10AS-0FE, 0AS-5FE, and 0AS-0FE. No significant differences were observed between 10AS-5FE and 10-3/SB. Microphotographs suggested that no hybrid layer formed in the 10AS-5FE group. Although the use of phosphoric acid and NaClO resulted in decreased bond strength between 4-META/MMA-TBB resin and dentin, additional conditioning with ascorbic acid and ferric chloride improved the bond strength.

Topics: Adhesiveness; Analysis of Variance; Animals; Ascorbic Acid; Boron Compounds; Cattle; Chlorides; Collagen; Dental Bonding; Dental Stress Analysis; Dentin; Dentin-Bonding Agents; Ferric Compounds; Materials Testing; Methylmethacrylates; Resin Cements; Sodium Hypochlorite; Tensile Strength

The effect of experimental dentin primers containing N-methylolacrylamide (MEAA) or N-methylolmethacrylamide (MEMA) on bond durability of a resin composite (Photo Clearfil A) with a bonding agent (Clearfil Photo Bond) to bovine dentin was investigated.. The etching agents were 10% maleic acid (10% MA), 10% phosphoric acid (10% PA) and 10% citric acid-3% ferric chloride (10-3 solution). Water solutions of 35% hydroxyethyl methacrylate (HEMA), 50% MEAA or 30% MEMA were used as dentin primers. The etched dentin was pre-treated with the dentin primers for 30s. The resin composite systems were applied in a Teflon tube positioned onto pre-treated dentin surfaces. After water immersion for 1 day and 5 years, the shear bond strengths were measured. The amounts of calcium dissolved with etching agents were measured using atomic absorption spectrometry. The thicknesses of hybrid layers at the dentin-resin interfaces treated with 6 mol/l HCl and 1% NaOCl were measured using scanning electron microscopy.. The bond strengths of the specimens (Controls) without primers to dentin etched with 10% MA and 10-3 solution significantly decreased after immersion in water for 5 years (p<0.05) while other bond strengths did not decrease. The bond strengths of the composites to MEMA- and MEAA-primed dentin were significantly higher than that of the control after 1 day, regardless of the types of etching agents (p<0.05). The 5 year bond strengths of the composites to HEMA-, MEMA- and MEAA-primed dentin were significantly higher than that of the control, regardless of the types of etching agents (p<0.05). The 1 day and 5 year bond strengths of the composite to MEAA-primed dentin were significantly higher than those of the composites to HEMA-primed dentin, regardless of the types of etching agents (p<0.05). The highest amount (182.3+/-8.0 microg/cm(2)) of dissolved calcium was determined for the pre-treatment with 10% PA, followed by that (152.0+/-6.9 microg/cm(2)) with 10% MA and that (140.1+/-2.8 microg/cm(2)) with 10-3 solution (p<0.05). The hybrid layer thicknesses (approximately 1 microm) for 10-3 solution were thinner than those (approximately 2 microm) for others after HCl immersion. For the controls, the hybrid layers after NaOCl immersion become narrower or disappeared. The main fracture pattern of specimens was a mixture of resin-dentin interface failure and dentin cohesive fracture after the bond test.. MEAA solution was more effective in improving the bond strength of the controls to etched dentin than was HEMA after 1 day and 5 years. Clearfil Photo Bond created good hybrid dentin layers which could resist NaOCl-attack and showed good dentin bond durability when dentin primers were used, regardless of the type of etching agent.

Topics: Acid Etching, Dental; Acrylamides; Analysis of Variance; Animals; Calcium; Cattle; Chlorides; Citric Acid; Composite Resins; Dental Bonding; Dentin; Dentin-Bonding Agents; Ferric Compounds; Hydrochloric Acid; Immersion; Maleates; Methacrylates; Microscopy, Electron, Scanning; Oxidants; Phosphoric Acids; Resin Cements; Sodium Hypochlorite; Spectrophotometry, Atomic; Stress, Mechanical; Surface Properties; Time Factors; Water

By altering either ferric chloride concentration in 10% citric acid (1% ferric chloride = 10-1; 5% ferric chloride = 10-5; 10% ferric chloride = 10-10) or conditioning periods with an aqueous mixture of 1% citric acid and 1% ferric chloride (1-1), the influence of dentin substrate on bond strength and hybridized dentin in wet bonding of 4-META/MMA-TBB resin was examined.. Dentin surfaces of fresh bovine incisors were conditioned either with 10-1, 10-5, or 10-10 mixtures for 10 s (10-1-10s, 10-5-10s, 10-10-10s groups) or with a 1-1 mixture for 5, 10, 30 or 60 s (1-1-5s, 1-1-10s, 1-1-30s, 1-1-60s groups). Rinsed, demineralized dentin samples were kept wet, primed with 5% 4-META in acetone for 60 s, and bonded with 4-META/MMA-TBB resin. Bonded specimens were trimmed to a mini-dumbbell shape for tensile testing. The cross sections of bonded specimens were modified with HCl and NaOCl in order to assess the hybrid layer. The fractured surfaces of specimens and the hybridized dentin were investigated with SEM.. No significant difference (p > 0.01) in tensile strength was identified between 10-1-10s and 10-5-10s groups (30 MPa), 10-10-10s and 1-1-5s groups (15 MPa), and the three groups conditioned by 1-1-10s, -30s and -60s (40 MPa). The thickness of the hybrid layer increased with increasing either ferric chloride or conditioning periods.. The concentration of ferric chloride in 10% citric acid for wet bonding must be less than 5% in order to provide a reliable bond. When applied from 10 to 60 s, the 1-1 conditioner provided hybridized dentin with reliable tensile bond strength. The thickness of the hybrid layer did not influence the tensile bond strength.

Topics: Acetone; Acid Etching, Dental; Acrylic Resins; Analysis of Variance; Animals; Boron Compounds; Cattle; Chelating Agents; Chlorides; Citric Acid; Dental Bonding; Dentin; Ferric Compounds; Hydrochloric Acid; Methacrylates; Methylmethacrylate; Microscopy, Electron, Scanning; Oxidants; Resin Cements; Sodium Hypochlorite; Statistics as Topic; Stress, Mechanical; Surface Properties; Tensile Strength; Time Factors; Water

The purpose of this study was to determine the relative contributions of the mineral and organic phases of dentin to its total buffering capacity and to compare the buffering abilities of normal and caries-affected dentin for acids used in adhesive dentistry.. Disks of normal and caries-affected human coronal dentin 0.6 mm thick were prepared. Fifty microL of various acids were applied to the surface of mineralized or completely demineralized dentin for varying lengths of time. They were collected from the surface and combined with water rinses to permit titration of the total amount of acid applied, the amount recovered, the total amount that was taken up by the dentin, and the amount that diffused across dentin into 1 mL of water. Equal volumes of acids were applied to mineralized or demineralized dentin powder or hydroxyapatite powder.. About 88% to 90% of applied acid was recovered from the surface; only 10% to 12% of the acid was taken up by dentin. Of the H+ that was taken up, only 1% to 2% actually diffused across 0.6 mm of dentin. Increasing the application time of 37% phosphoric acid did not increase the amount of H+ that diffused across dentin. Increasing the concentration of phosphoric acid from 10% to 65% produced only slight increases in H+ diffusion across dentin. There was no difference in the buffering capacity of normal vs caries-affected dentin disks. Almost all of the buffering capacity of dentin is due to its mineral phase.. The high buffering capacity of dentin and the high reactivity of H+ insure that little H+ diffuses through dentin more than 0.6 mm thick.

Topics: Analysis of Variance; Buffers; Chlorides; Citric Acid; Confidence Intervals; Dental Caries; Dentin; Diffusion; Durapatite; Ferric Compounds; Humans; Hydrogen-Ion Concentration; Minerals; Oxidants; Phosphoric Acids; Protons; Sodium Hypochlorite; Statistics as Topic; Time Factors

This study compared the capability of three composite resin cements to sustain a standard endodontic dowel. All of the systems incorporated some form of smear layer removal on the dentin of the endodontic channel. One system that used a methyl ethyl ketone drying agent provided inadequate clinical resistance to dislodgment of 5.4 DaN. A second cementing system that used only smear layer removal resisted loads at 54.7 DaN. The third cementing regimen that included a surface-initiated dentinal adhesive and smear layer removal recorded retention of 77.4 DaN. This study supported the concept that passively cemented dowels with composite resin can be as effective as actively seated dowels.

Topics: Acrylic Resins; Bisphenol A-Glycidyl Methacrylate; Boron Compounds; Butanones; Cementation; Chlorides; Citrates; Citric Acid; Composite Resins; Dental Bonding; Dental Cements; Dental Implantation, Endosseous, Endodontic; Edetic Acid; Ferric Compounds; Humans; Methacrylates; Methylmethacrylates; Polyethylene Glycols; Polymethacrylic Acids; Prosthesis Failure; Root Canal Irrigants; Root Canal Therapy; Smear Layer; Sodium Hypochlorite; Stress, Mechanical