This paper focuses on the development of high temperatures in the cutting zone during high performance grinding. In order to identify the infl uence of grinding temperature on surface integrity, temperatures were measured in the workpiece surface layer under diff erent machining conditions. Beside this, under the same conditions, the surface layer properties of the workpiece material were deter...

objective: iron deficiency anemia is among the most common types of childhood anemia. according to the world health organization, approximately 5 billion people were suffering from iron deficiency anemia worldwide in 2001. aside from causing anemia, iron deficiency can negatively affect the physical and mental development of children and adolescents. several studies have discussed the consequen...

The aim of this study was to evaluate the surface roughness, microhardness and morphology of human enamel exposed to six bleaching agents (at baseline and post-treatment). Human dental enamel samples were obtained from human third molars and randomly divided into seven groups (n = 11): control, Whiteness Perfect 10% carbamide peroxide (10% CP), Colgate Platinum 10% CP, Day White 2Z 7.5% hydroge...

OBJECTIVES This study investigated the effects of post bleaching treatments to prevent restaining and the change of enamel surface microhardness after dental bleaching in vitro. METHODS Sixty intact human incisor teeth were stained in tea solution and randomly assigned into four groups (n=15). Then samples were bleached for two weeks (8 hours daily) by 15% carbamide peroxide. Tooth color was ...

This study evaluated the influence of curing method and storage condition on the microhardness of dual-cure resin cements: Panavia F 2.0 (PF) and Nexus 2 (NX). The specimens were either light-cured (LC) or chemically cured in darkness (CC). After 24 hours of storage in dry chamber (Dry) or distilled water (DW), the specimens were sectioned and polished. The microhardness of resin cement matrix ...

The purpose of the research was to determine the effect of nano-hydroxyapatite concentrations on initial enamel lesions under dynamic pH-cycling conditions. Initial enamel lesions were prepared in bovine enamel with an acidic buffer. NaF (positive control), deionized water (negative control) and four different concentrations of nano-hydroxyapatite (1%, 5%, 10% and 15% wt%) were selected as the ...

in the present work the effects of plasma nitridization on the passivation behavior of aisi 316l was investigated. to do this; nitriding treatments were carried out at 420°c for 1, 2, 4 and 16 hours. the phase composition and structure of the nitrided layer were studied by low angle x-ray diffraction and scanning electron microscopy. the hardness of samples also was evaluated by vickers microha...

Aims: To measure the microhardness of root canal dentin using two types of irrigating solutions( 0.2% Chlorhexidine and 5.25% Sodium Hypochlorite) with and with out use of different types of root canal files (Stainless Steel-K files, Nickel-Titanium K-files or rotary Nickel-Titanium files). Materials & methods: The teeth divided in to four groups according to the type of irrigating solutions th...

BACKGROUND To evaluate and compare the microhardness of deciduous teeth treated with nano-hydroxyapatite and calcium sucrose phosphate after iron drop exposure. MATERIAL AND METHODS Twenty healthy anterior deciduous teeth were collected and stored in 0.9% saline solution at room temperature. All the teeth were immersed in artificial saliva in an incubator shaker at 37° for an hour and then su...

The purpose of this study was to evaluate the microhardness of resin-based materials polymerized with a LED (light-emitting diode) light-curing unit (LCU) and a halogen LCU. Twenty cylindrical specimens (3.0 mm in diameter and 2.0 mm high) were prepared for each tested material (Z100, Definite and Dyract). Specimens were light-cured with two LCUs (Ultraled and Curing Light 2500) for either 40 o...