Background: Nickel-titanium (NiTi) archwires have become increasingly popular because of their ability to release constant light forces, which are especially useful during initial alignment and leveling phase. The aim of the present study was to investigate and compare the load–deflection characteristics of four commercially available NiTi archwires. Materials and methods: 200 NiTi 0.014, 0.016, 0.018, 0.016x0.022 and 0.019x0.025-inch nickel–titanium archwires from four different manufacturers (3M, Ortho Technology, Jiscop and Astar) were tested. The load-deflection properties of these archwires were evaluated by a full arch bending test in both palatal and gingival directionsat 37°C temperature using a universal material testing machine. Forces generated at maximumloading of 2mm and at unloading of 1.5mm were measured. Results: All the tested NiTi wires showed an increase in loading and unloading force with increased wire dimension.Generally, 3M gave the most flexible round wires and relatively stiff rectangular wires; with linear load deflection curves. Ortho Technology wires were flexible. Jiscop gave the stiffest round wires and the most flexible rectangular wires. Astar wires were stiff which gave the highest force levels during unloading. Conclusion: Force levels vary greatly from brand to brand and soNiTi wire brands must be selected with consideration to their load-deflection characteristics and mechanical properties.
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Osteoporosis (OP) is a systemic skeletal disorder that is characterized by reduced bone mass and micro-architectural deterioration of bone tissue, with a consequent increase in bone fragility and susceptibility to fracture. The most frequent osteoporotic fractures are fractures of the hip, wrist, and spine. The exact causes of OP are still unknown; several factors contribute to the disorder. Subjects and Methods: This study consists of patient groups, this group (Group A) was composed of 80 postmenopausal women with OP and osteopenia and the patient group was subdivided into two group; First group (GroupA1) was composed of 50 postmenopausal women with OP and the second group (Group A2) composed of (30) Postmenopausal Women with oste
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Background: The present study involved the following parts, the first part is evaluation of the levels of glycated hemoglobin(HbA1c), creatinine, uric acid(UA) and albumin in patients with diabetic nephropathy comparison with the group of healthy as a control group. The second part is the measurement and evaluation of oxidative stress represented in the malondihydehyde(MDA) as a biomarker of oxidative stress as well as the identification of vitamins C and E as an antioxidant in patients with diabetic nephropathy(DN) compared with the healthy group. Objective: The objective of this study is to estimate oxidative stress by calculate malondialdehyd as biomarker and evaluate some vitamins such as vit C and vit E as antioxidants in diabetic neph
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The discovery of novel therapeutic molecules is always difficult, and there are a variety of methodologies that use the most diverse and innovative medicinal chemistry approaches. One such approach is the deuteration technique: Deuteration is the process of substituting deuterium for hydrogen in a molecule. When compared to the drug molecule, its deuterated analogues may retain the features of the original molecule and, in some cases, improve its pharmacological activity, with fewer side effects and lower toxicity. Metronidazole is a commonly used antibiotic to treat anaerobic bacterial infections, protozoal and microaerophilic bacterial infections. Met
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