We evaluated the effect of phytic acid on matrix metalloproteinase (MMP)- or cysteine cathepsin (CC)-mediated dentin degradation. Demineralized beams were divided into five groups (n = 12) and treated with 1%, 2%, 3% 37% phosphoric acid. Untreated demineralized served as controls. After incubation for 1 3 wk, dry mass loss was determined aliquots media analysed cross-linked telopeptide type I c...

Multi-mode universal adhesives (UA) are indicated as either self-etch or etch-and-rinse adhesives, and manufacturers also recommend an alternative ‘selective enamel etch’ technique. Currently available laboratory data support phosphoric acid selective etching of enamel prior to use of UA to improve bond strength. In another way to improve adhesion to enamel of UA without the use of phosphoric a...

AIM To evaluate and compare ex vivo the decalcifying effect of 15% EDTA, 15% citric acid, 5% phosphoric acid and 2.5% sodium hypochlorite on root canal dentine. METHODOLOGY Two 2-mm-thick slices were cut from the coronal third of the root of 10 human incisors. Each slice was sectioned into two equal parts. Specimens were assigned to one of four groups (n = 10) for immersion in 20 mL of either...

The purpose of this study was to examine the feasibility of a conditioner for treating enamel and dentin simultaneously for MMA-TBB resin bonding. Various phosphoric acid solutions containing copper salts were prepared and used as conditioners before bonding MMA-TBB resin to bovine teeth. Their effects on the surface morphology and bonding were studied by scanning electron microscopy and tensil...

Solvent extraction using organic solvents is an important technology for the purification of wet process phosphoric acid (WPA). In this study, the purification process of WPA, using a new type of solvent extraction system, cyclohexanol diluted in kerosene, was investigated. The equilibrium phase diagram of the system H3PO4 H2Osolvent mixtures at 313.2K was obtained. The effects of extraction ...

OBJECTIVE The aim of this study was to evaluate the effect of feldspathic ceramic surface cleaning on micro-shear bond strength and ceramic surface morphology. MATERIAL AND METHODS Forty discs of feldspathic ceramic were prepared and etched with 10% hydrofluoric acid for 2 minutes. The discs were randomly distributed into five groups (n=8): C: no treatment, S: water spray + air drying for 1 m...

A reinvestigation of a chiral phosphoric-acid-catalyzed four-component Hantzsch enantioselective synthesis polyhydroquinolines reported in 2009 is presented. In our hands, when the reaction was performed with fidelity to original report using enantiopure phosphoric acid catalyst, no enantioselectivity observed. Unlike report, results are backed by baseline separation enantiomers HPLC analyses o...

The flaky graphites were prepared from lignite. The effects of phosphoric acid ratios and pyrolysis temperatures on flake formation were studied by SEM, TEM and XRD. The results showed that the flaky graphite occurred at a pyrolysis temperature of 600°C with a 1.0:1.0 ratio of carbon to phosphoric acid. The flaky formation was almost completed by pyrolysis at 800°C and with a 1:2.0 ratio of car...

1. Mycelium of Rhizopus nigricans when stained with certain acid and basic dyes and washed with buffer mixtures of 0.1 M phosphoric acid and sodium hydroxide responded much like an amphoteric colloid with an isoelectric point near pH 5.0. 2. When grown on potato dextrose agar the reaction of which was varied with phosphoric acid the extent of colony growth of Rhizopus nigricans plotted against ...