The viscosity of some sugars varies continuously by approximately 10 orders of magnitude over a temperature range of 50 degrees C. Sugars are therefore ideal model materials for studying the failure mechanism of materials as they change from the solid to the liquid state. We have used a surface forces apparatus coupled to interference and optical microscopy imaging to study the way two sugar su...

This study evaluated the bond strength of veneering porcelain with an experimental conditioner-coated zirconia. Pre-sintered Y-TZP specimens (n = 44) were divided in two groups based on conditioning type. After sintering, all sample surfaces were sandblasted and layered with veneering porcelain. Additionally, half of the specimens in each group underwent thermal cycling (10,000 cycles, 5-55 °C)...

OBJECTIVES To evaluate the effect of root canal sealers (RCS) and specimen aging on the bond strength of fibre posts to bovine intraradicular dentin. MATERIAL AND METHODS 80 teeth were used according the groups - Sealapextm, Sealer 26®, AH Plus® and specimens aging - test with no aging and with aging. The canals prepared were filled using one of each RCS. The posts were cemented. Roots were cr...

The strength and deformation of full-scale adhesively bonded multi-material joints is studied in this paper. Four with a thick layer methyl methacrylate adhesive (MMA) have been manufactured shipyard conditions. In two specimens, cracks introduced at steel–adhesive composite–adhesive interfaces. One cracked one un-cracked specimen were subjected to quasi-static tensile testing; the remaining sp...

We employ a genetic algorithm to maximize the energy dissipated per unit areal density in laminates composed of layers of poly-methyl-metha-acrylate (PMMA), adhesive and polycarbonate (PC) impacted at low velocity by a rigid hemi-spherical nosed cylinder. Sources of energy dissipation considered are plastic deformations of the PC and the PMMA, cracking of the PMMA, viscous deformations of the a...

This in vitro study evaluated the shear bond strength (SBS) between ceramic brackets (CBs) and resin composite restorations (RCRs) prepared using different surface treatments. The findings were also compared with a similar study that used stainless steel brackets (SSBs). Forty-five premolars were restored with a nano-hybrid composite resin (Tetric EvoCeram) and randomly assigned to three surfac...

BACKGROUND Bond strength of adhesive layer can absorb unwanted stresses of polymerization shrinkage in composite resin restorations; increased microshear bond strength can prevent failure of restoration materials, the purpose of this study was to evaluate the effect of adhesive layers on microshear bond strength of nanocomposite resin to dentin. MATERIAL AND METHODS Two different types of adh...

The adhesive monomer, Clearfil New Bond, was used to enhance the bond strength between orthodontic brackets and primary molars, premolars, and NiCr crowns. Twenty specimens of each had this dental adhesive applied according to the manufacturer's instructions in addition to a chemically cured composite material. The remaining specimens (20 each) were bonded without the adhesive monomer. Shear bo...

statement of the problem: various methods such as light emitting diode (led) have been used to enhance the polymerization of resin-based orthodontic adhesives. there is a lack of information on the advantages and disadvantages of different light curing systems. purpose: the aim of this study was to compare the effect of led and halogen light curing systems on the shear bond strength of orthodon...

OBJECTIVES The purpose of this paper was to review current literature on the clinical effectiveness of contemporary adhesives when used to restore cervical non-carious class-V lesions. Restoration retention in function of time was recorded in order to find out if adhesives with a simplified application procedure are as clinically effective as conventional three-step adhesives. DATA SOURCES Li...