pyrophosphate and phosphoric-acid

To evaluate the microleakage around class V restorations restored with either a self-etching adhesive system or a conventional two-bottle adhesive system used with "total etch" technique, and their recommended resin-based composites (RBC).. Two types of adhesive systems were used. A self-etching adhesive, Etch and Prime 3.0 (Degussa AG, Hanau, Germany), and a conventional two-bottle adhesive, Gluma Solid Bond (Heraeus Kulzer, Dormagen, Germany). The bonding systems were used in strict accordance with the manufacturers' instructions, except that, with the two-bottle adhesive system, the cavities were filled with either a "wet" or a "dry" bonding technique, subsequent to acid-etching with 20% phosphoric acid. Etch & Prime 3.0 was used in conjunction with Degufill Mineral (Degussa, Hanau, Germany) RBC and Gluma Solid Bond with Flow Line RBC (Heraeus Kulzer, Dormagen, Germany). Standardised bucco-cervical cavities were prepared on the buccal and lingual surfaces of 15 extracted maxillary first premolar teeth; all cavity margins were in enamel. Ten of the resulting cavities (Group A) were restored using Etch & Prime 3.0 and Degufill Mineral, ten (Group B) using Gluma Solid Bond (Wet Bond), and ten (Group C) using Gluma Solid Bond (Dry Bond). Leakage scores at occlusal and gingival margins were calculated after thermocycling 500 times between baths, held at 5 degrees C and 55 degrees C, respectively, with 30 seconds dwell time in both. Data were analysed by the Fisher Exact Test.. There was no statistically significant difference between the self-etching adhesive and conventional two-bottle adhesive systems at either the occlusal or the gingival margins. With the self-etching adhesive, there was no statistically significant difference in leakage scores between occlusal and gingival margins. There was a statistically significant difference between the occlusal and the gingival margins when a "wet" or "dry" bonding technique was used with the conventional two-bottle adhesive system.. The results suggest that the application of a conventional two-bottle bonding system used with a "total etch" technique is better than that of a self-etching adhesive system. With the former, the use of a "wet" bonding does not give better results than a "dry" bonding technique.

Topics: Acid Etching, Dental; Adolescent; Adult; Child; Composite Resins; Dental Bonding; Dental Cavity Preparation; Dental Cements; Dental Enamel; Dental Leakage; Dental Marginal Adaptation; Dental Materials; Diphosphates; Ethanol; Fluorides; Glutaral; Humans; Materials Testing; Methacrylates; Phosphoric Acids; Polymethacrylic Acids; Surface Properties

To evaluate the degradation of resin-enamel interfaces bonded with different adhesive systems.. Flat enamel surfaces were ground buccally on bovine incisors. Two etch & rinse self-priming adhesives (Single Bond, Prime & Bond NT), three two-step self-etch adhesives (Clearfil SE Bond, Resulcin Aquaprime, NRC/Prime & Bond NT) and two all-in-one adhesives (Etch & Prime 3.0, Adper Prompt-L-Pop) were used for bonding. A hybrid resin composite (Tetric Ceram) was selected for coronal build-up. Bonded specimens were stored in water at 37 degrees C for 24 hours, 6 months and 1 year, respectively, and then sectioned into 1 mm2 beams. Each microtensile stick was loaded in tension until failure (crosshead speed: 0.5 mm/minute). Bond strength data were analyzed with two-way ANOVA and Student Newman Keuls tests (P < 0.05). Etching patterns resulting from phosphoric acid etching and self-etch adhesives application on ground enamel were analyzed under SEM.. All adhesives attained similar bond strengths after 24 hours. All-in-one adhesives and Resulcin Aqua Prime recorded a significant reduction in bond strengths after 6 months and 1 year of water aging.

Topics: Acid Etching, Dental; Animals; Bisphenol A-Glycidyl Methacrylate; Cattle; Composite Resins; Dental Bonding; Dental Enamel; Dental Materials; Dentin-Bonding Agents; Diphosphates; Ethanol; Maleates; Materials Testing; Methacrylates; Microscopy, Electron, Scanning; Phosphoric Acids; Polymethacrylic Acids; Random Allocation; Resin Cements; Stress, Mechanical; Surface Properties; Temperature; Tensile Strength; Time Factors; Water

There are no data available on whether or to what extent hydrofluoric acid affects the marginal integrity of dentin-bonded composite restorations when it is used instead of phosphoric acid in the total-etch technique.. This in vitro study examined the etching effects of phosphoric acid versus a combination of phosphoric and hydrofluoric acid by evaluation of microleakage in a composite restoration bonded with different dentin adhesive systems.. Extracted teeth (n = 90) containing 2 class II preparations, mesial occlusal (MO) and distal occlusal (DO) standarized (cervical margins in dentin) were perfused with Ringer solution and etched in 1 of 2 ways: with phosphoric acid only or with phosphoric combined with hydrofluoric acid. Different dentin bonding agents were then applied (Etch & Prime 3.0, Optibond Solo, Prime & Bond NT, Scotchbond 1, Syntac Single Component, or Syntac Sprint; (n = 15 for each etching material)). The preparations were restored with a hybrid composite (Herculite XRV) and submitted to 5000 thermocycles (5 degrees C to 55 degrees C) to simulate the in vivo situation. Microleakage was assessed with 2% methylene blue diffusion for 24 hours. Dye penetration was calculated as a percentage of the total length of the gingival margins of the preparation with light microscopy at original magnification x 32. The results were analyzed with the Kruskal-Wallis multiple comparison z-value assay (alpha = .05).. Differences in dye penetration were significant, both as a function of the dentin adhesive and the conditioning mode applied. In the specimen groups conditioned with phosphoric acid, Optibond Solo (54% +/- 44%) and Syntac Sprint (74% +/- 39%) demonstrated the lowest penetration values. Higher values were obtained for Prime & Bond NT (81% +/- 34%), Scotchbond 1 (83% +/- 31%), Etch & Prime 3.0 (85% +/- 33%), and Syntac Single Component (95% +/- 16%), with no significant differences (alpha=.05) between specimen groups. The best results were obtained for Syntac Sprint (24% +/- 26% dye penetration) after conditioning with a mixture of phosphoric and hydrofluoric acid. The least favorable result was obtained for Optibond Solo (65% +/- 31%). It was significantly different from Prime & Bond NT (76% +/- 37%), Scotchbond 1 (85% +/- 29%), and Etch & Prime 3.0 (88% +/- 24%). Syntac Single Component (75% +/- 32%) was significantly different from Syntac Sprint. Syntac Single Component and Syntac Sprint exhibited significantly better results when conditioned with a combination of phosphoric acid and hydrofluoric acid than with phosphoric acid only.. Within the limitations of this in vitro study, total-etching water-based (Syntac Single Component) and acetone-based (Syntac Sprint) bonding agents with a combination of phosphoric acid and hydrofluoric acid led to significant reductions (alpha=.05) in dye penetration compared to phosphoric acid conditioning only. Ethanol-based dentin bonding agents (Etch & Prime 3.0, Optibond Solo, and Scotchbond 1) were not significantly influenced by the type of conditioner used.

Topics: Acid Etching, Dental; Acrylates; Bisphenol A-Glycidyl Methacrylate; Dental Leakage; Dental Marginal Adaptation; Dental Restoration, Permanent; Dentin; Dentin-Bonding Agents; Diphosphates; Ethanol; Humans; Hydrofluoric Acid; Maleates; Methacrylates; Phosphoric Acids; Polymethacrylic Acids; Resin Cements; Statistics, Nonparametric

Topics: Ammonia; Calcium Sulfate; Diphosphates; Jordan; Manure; Phosphoric Acids

This paper reports the effectiveness of 0.1% (W/V) quinoline-8-ol, 0.5% (V/V) phosphoric acid and 0.5% (W/V) sodium pyrophosphate as stabilizers of stock solutions on peracetic acid. The three solutions were put separately as stabilizers into stock solutions of peracetic acid in the laboratory. They were stored at room temperature for approximately one year, and the percent of peracetic acid content was determined at regular intervals. Also, we made studies on different concentrations of phosphoric acid for different prescriptions of peracetic acid. The results show that 0.1%, 0.3% and 0.5% (V/V) phosphoric acid and 0.5% (W/V) sodium pyrophosphate were not effective stabilizers for the stock solutions of peracetic acid. Therefore, phosphoric acid or sodium pyrophosphate is not an effective stabilizer in stockpiling stock solutions of peracetic acid.

Topics: Diphosphates; Drug Stability; Excipients; Oxyquinoline; Peracetic Acid; Phosphoric Acids

Topics: Adenine Nucleotides; Adenosine; Adenosine Diphosphate; Amides; Cobamides; Diphosphates; Guanosine; Guanosine Diphosphate; Nucleosides; Nucleotides; Phosphates; Phosphoric Acids; Vitamin B 12