Evaluation of the effect of adding micro-hydroxyapatite and nano-hydroxyapatite on the microleakage of conventional and resin-modified Glass-ionomer Cl V restorations.

Background: Pulpal reaction to restorative materials depends on marginal microleakage, which is a dynamic phenomenon that allows bacteria and fluids to traverse across the tooth-restoration interface. Glass-ionomer cement (GIC) exhibits low microleakage due to direct bonding to tooth structures. Hydroxyapatite (HAP) based on the similarity with tooth structure may decrease the microleakage.

Effect of Dimethyl Sulfoxide on Bond Strength of a Self-Etch Primer and an Etch and Rinse Adhesive to Surface and Deep Dentin.

Statement Of The Problem: Composite bond to dentin is crucial in many clinical conditions particularly in deep cavities without enamel margins due to insufficient penetration of adhesive into demineralized dentin.

Purpose: The aim of this study was to assess the shear bond strength (SBS) of a methacrylate-based and a silorane-based composite resin to surface and deep dentin after pretreatment with dimethyl sulfoxide (DMSO).

Materials And Method: Eighty extracted human premolars were randomly divided into two groups of flat occlusal dentin with different cuts as A: surface group (sections just below the dentinoenamel junction (DEJ) and B: deep group (2 mm below DEJ).

Effect of MRI on the mechanical properties of stainless steel orthodontic wires.

Aim: To assess whether the forces created by the magnetic resonance imaging (MRI) field cause a deflection of orthodontic stainless steel archwires or a change of their mechanical properties.

Methods: Sixty stainless steel 0.016-inch archwires were divided into three groups of 20 wires each.