ABSTRACT
PURPOSE: To evaluate the effect of resin coating of bonded dentin on the micro-tensile bond strengths of a resin cement to dentin over 1 year. METHODS: Human molars were ground to obtain flat dentin surfaces and divided into three groups. The dentin surfaces were left as a control, or resin-coated with a combination of a dentin bonding system, Clearfil SE Bond (SE), and one of two lining materials: Protect Liner F (PLF) (SE/PLF) or Ionosit Micro Spand (IMS). The dentin surfaces with or without resin coating were covered with a temporary filling material (Cavit-G) and stored in water for 1 day. After removal of Cavit-G, an indirect composite block (Estenia) was bonded with Panavia F following the manufacturer's instructions. The specimens were stored in water for 1 day, 6 months or 1 year in 37 degrees C water. Micro-tensile bond strength was measured at a crosshead speed of 1 mm/minute. There were 10 slices each group. Data were analyzed with two-way ANOVA and Fisher's PLSD test (P < 0.05). RESULTS: ANOVA indicated that resin coating and storage period significantly influenced the micro-tensile bond strengths (P < 0.0001). The bond strengths of SE/PLF, SE/IMS and the control after 1 day were 27.5 +/- 5.1, 15.7 +/- 3.2 and 10.6 +/- 4.9 MPa, respectively. The bond strengths of SE/PLF significantly decreased over 1 year (P < 0.05), while there were no significant differences in bond strengths for SE/IMS (P > 0.05). The bond strengths of SE/PLF were significantly higher than those of the control over 1 year (P < 0.05).
Subject(s)
Composite Resins/chemistry , Dental Bonding , Dentin-Bonding Agents/chemistry , Dentin/ultrastructure , Resin Cements/chemistry , Compomers/chemistry , Dental Cements/chemistry , Drug Combinations , Humans , Materials Testing , Methacrylates/chemistry , Microscopy, Electron, Scanning , Polyurethanes/chemistry , Polyvinyls/chemistry , Stress, Mechanical , Surface Properties , Temperature , Tensile Strength , Time Factors , Water/chemistry , Zinc Oxide/chemistryABSTRACT
The purpose of this study was to evaluate the microtensile bond strength (MTBS) of a waterless all-in-one adhesive system, Absolute, to dentin. Eighteen human molars were either ground with 600-grit SiC paper or cut with a diamond bur. The following dentin bonding procedures were then performed: dentin surface was kept moist; dentin surface was dried; or dentin surface was dried but equivalent amount of water was added to the adhesive (1:1 by volume). After adhesive curing, a resin composite was incrementally built up. After the specimens were kept in water for one day, MTBSs were measured at a cross-head speed of 1 mm/min. Two-way ANOVA (p = 0.05) indicated that the MTBS of the adhesive system was not influenced by surface texture, but enhanced by the presence of water on tooth surface. It was concluded that water is essential to obtaining good dentin bonding for this adhesive system.
Subject(s)
Dental Bonding , Dentin-Bonding Agents , Resin Cements , Analysis of Variance , Chi-Square Distribution , Dental Stress Analysis , Dentin , Dentin Permeability , Humans , Materials Testing , Microscopy, Electron, Scanning , Molar , Smear Layer , Tensile Strength , WettabilityABSTRACT
PURPOSE: To analyze in vitro artificial secondary caries inhibition around conventional luting cements and resin cements using a confocal laser-scanning microscope (CLSM). METHODS: Box shape cavities (approximately 3 mm long, 4 mm wide, and 1.5 mm deep) were prepared in bovine root dentin. One of five cements: Elite Cement 100 (EL) zinc phosphate cement, HY-Bond Carbo Cement (CA) polycarboxylate cement, Fuji I (FI) glass-ionomer cement, Fuji Luting (FL) GIC-based resin cement and Panavia F (PA) fluoride-releasing resin cement, was placed in the cavity. After polishing, the center of the cement surface was covered with an adhesive to preserve the original cement solubility. The specimens were stored in distilled water at 37 degrees C for 1 week, and stored in an artificial demineralizing solution for 3.5 days. Following this, each specimen was sectioned into two halves, trimmed, and polished. Thickness of inhibition zone, depth of outer lesion and cement solubility around each cement were determined by a CLSM. RESULTS: Inhibition zones were not seen in EL and CA, while they were found in FI, FL and PA. The depths of the outer lesions of CA and FI were significantly lower than those of EL, FL and PA (P< 0.05). The highest and the second-highest cement solubility were obtained in EL and CA, respectively. FI and FL indicated significantly lower cement solubility than EL and CA. PA tended to show the lowest cement solubility.
