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 aim of this in vitro study was to evaluate quantitatively the microleakage in class V cavities restored with one-bottle and self-etching adhesive systems with and without previous acid etching. Two one-bottle adhesive systems (Single Bond and Prime & Bond 2.1) and one self-etching adhesive system (Clearfil Mega Bond) were used in this study. One hundred and twenty sound human premolar teeth...

In complexes of the transition metals containing clusters of metal atoms the cobalt-cobalt bond lengths are almost always within 1 pm of the single-bond value 246 pm given by the enneacovalent radius of cobalt, whereas most of the observed iron-iron bond lengths are significantly larger than the single-bond value 248 pm, the mean being 264 pm, which corresponds to a half-bond. A simple discussi...

Controlled step-by-step dissociation of single iodobenzene molecules has been performed at Cu(111) step-edges using tunneling electrons from a scanning tunneling microscope (STM) tip at 12 K. We show that the threshold tunneling electron energies to break a single bond inside a polyatomic molecule can be determined by using I-V spectroscopy of single molecules. Electron energies of 1.5±0.1 eV a...

The zinc(II) complex [Zn2(dmdtc)2(μ-dmdtc)2] has been synthesized directly from thiram ligand, containing a disulfide bond {dmdtc = N,N-dimethyldithiocarbamate; thiram = N,N-tetramethylthiuram disulfide}, and characterized by elemental analysis and spectroscopic methods. Surprisingly thiram, undergoes a reductive disulfide bond scission upon reaction with Zn2+ in methanolic media to give the [Z...

calcium hydroxide is the most widely used intracanal medicament in endodontics, which should be removed prior to permanent root canal filling to minimize its intervention with the bonding of endodontic sealers. this ex-vivo study aimed to evaluate the effect of pretreatment with calcium hydroxide on the bond strength of resilon/epiphany self etch (se) to the radicular dentin after removing the ...