maleic-acid and ferric-chloride

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

To investigate the effect of dentin treatment with mixed solutions of citric acid and ferric chloride on the tensile bond strength of resin-modified glass ionomers.. 120 freshly extracted bovine incisors were ground to expose dentin surface. Vitremer and Fuji II LC were bonded to dentin surfaces that were (1) rinsed with distilled water and dried with oil-free compressed air, (2) treated with Super Bond Dentin Activator for 30 seconds, (3) treated with Bondwell LC Conditioner for 20 seconds, (4) treated with Scotchbond Multi-purpose Etchant for 15 seconds, (5) treated with Dentin Conditioner for 20 seconds, or (6) treated with K-etchant for 40 seconds following manufacturers' recommendations. Specimens were stored in water at 37 degrees C for 24 hours. The tensile bond strength was measured at a crosshead speed of 0.5 mm/minute. The data were statistically analyzed by a one-way ANOVA and Dunnett's Post-hoc Procedure (P < 0.05).. Super Bond Dentin Activator and Bondwell LC Conditioner increased the tensile bond strength of Vitremer and Fuji II LC. Scotchbond Multi-purpose Etchant, Dentin Conditioner, and K-etchant did not improve the tensile bond strength of Vitremer and Fuji II LC.

Topics: Acid Etching, Dental; Acrylic Resins; Analysis of Variance; Animals; Cattle; Chlorides; Citric Acid; Composite Resins; Dental Bonding; Dentin; Ferric Compounds; Glass Ionomer Cements; Maleates; Materials Testing; Phosphoric Acids; Resins, Synthetic; Tensile Strength

This study used scanning electron microscopy (SEM) to evaluate the effects of various acid conditioners (etchants) on dentine surfaces. The conditioners completely removed the smear layer from dentine and opened the dentinal tubules, but some also left debris or a reaction product on the surface. The study also evaluated the resin-dentine interfaces produced by five new-generation dentine bonding systems: All-Bond 2, Amalgambond, Gluma 2000, OptiBond, and Scotchbond Multi-Purpose. All-Bond 2, Amalgambond, OptiBond, and Scotchbond Multi-Purpose formed acid-resistant hybrid layers and intra-tubular resin tags when they were applied to visibly moist dentine.

Topics: Acid Etching, Dental; Adhesives; Aluminum Compounds; Bisphenol A-Glycidyl Methacrylate; Chlorides; Citrates; Citric Acid; Composite Resins; Dentin; Dentin-Bonding Agents; Ferric Compounds; Glutaral; Humans; Maleates; Methacrylates; Microscopy, Electron, Scanning; Nitrates; Oxalates; Oxalic Acid; Phosphoric Acids; Polymethacrylic Acids; Resin Cements; Smear Layer; Surface Properties

Although various adhesive resins for dentin have been developed and used clinically, most attention has been directed to adhesion-promoting monomers and pre-treatment agents. The role of polymerization initiator systems in bonding has been overlooked. The purpose of this work was to study the role of initiators from the viewpoint of interfacial initiation of polymerization in dentin bonding. The bond strength between dentin and methyl methacrylate resin was significantly improved by a possible interfacial initiation with (1) the combination of ferric chloride, adsorbed onto dentin, and oxidized tri-n-butylborane (TBBO) and (2) the addition of tertiary butyl peroxymaleic acid (containing a carboxylic acid group, which has an affinity with dentin) to chemically- or light-activated initiator systems.

Topics: Acid Etching, Dental; Acrylic Resins; Adhesives; Boron Compounds; Chlorides; Dental Bonding; Dental Cements; Dentin; Ferric Compounds; Maleates; Materials Testing; Methacrylates; Methylmethacrylate; Methylmethacrylates; Tensile Strength