STATEMENT OF THE PROBLEM Some studies have reported the bond strength to be significantly lower in fluorotic enamels than the non-fluorosed. PURPOSE The purpose of this study was to evaluate the shear bond streongth of metallic brackets to non-fluorosed and fluorosed teeth after different enamel conditioning. MATERIALS AND METHOD A total of 176 freshly extracted human premolars (88 non-fluo...

The central goal of this study was to characterize the mental models of acids and acid strength expressed by advanced college chemistry students when engaged in prediction, explanation, and justification tasks that asked them to rank chemical compounds based on their relative acid strength. For that purpose we completed a qualitative research study involving students enrolled in different types...

AIM This study evaluated the effect of three different contamination removal methods on bond strength of one-step self-etching adhesive to dentin contaminated with an aluminum chloride hemostatic agent. MATERIALS AND METHODS One hundred noncarious adult molars were used in this study; 2-mm-thick dentin disks were prepared and randomly assigned to 5 groups (n = 20). Group I: control; group II:...

Ensemble-averaged deprotonation energies (DPE) derived from periodic density functional theory models are insensitive to the location of isolated Al atoms and associated protons and similar among microporous aluminosilicates (i.e., zeolites) with different crystalline frameworks (MFI, BEA, FER, MOR, CHA, FAU). These DPE values are 1201 ± 11 kJ mol−1 after correcting for systematic artifacts of ...

introduction : this in vitro study was designed to evaluate the effect of smear layer removal on push-out bond strength of white mineral trioxide aggregate (wmta) and calcium-enriched mixture cement (cem). materials and methods: dentin discs with 3 mm thicknesses were divided into 4 groups ( n =15): group 1: irrigation of the canal with normal saline and filling with wmta; group 2: irrigation w...

In this study, an injectable bone substitute (IBS) consisting of citric acid, chitosan, and hydroxyl propyl methyl cellulose (HPMC) as the liquid phase and tetra calcium phosphate (TTCP), dicalcium phosphate dihydrate (DCPD) and calcium sulfate dehydrate (CSD, CaSO4 x 2H2O) powders as the solid phase, were fabricated. Two groups were classified based on the percent of citric acid in the liquid ...