Several studies have reported the benefits of sonic and/or ultrasonic instrumentation for root debridement, with most of them focusing on changes in periodontal clinical parameters. The present study investigated possible alterations in the tensile bond strength of crowns cemented with zinc phosphate cement to natural teeth after ultrasonic instrumentation. Forty recently extracted intact human...

introduction: laser tissue soldering using albumin and indocyanine green dye (icg) is an effective technique utilized in various surgical procedures. the purpose of this study was to perform laser soldering of rat skin under a feedback control system and compare the results with those obtained using standard sutures. material and methods: skin incisions were made over eight rats’ dorsa, which w...

in this study, friction stir spot welding (fssw) is applied to join the tial6v4 titanium alloy with 1.5 mm thickness and then the effect of rotational speed and tool dwell time on microstructure and mechanical properties is investigated. in this regard, the speed of the tool rotation was considered as 800, 1000, and 1200 rpm, as well as the tool dwell time was set at 7 and 12s. microstructural ...

Leaf-level photosynthetic-light response and plant-level daily carbon gain were estimated for seedlings of moderately shade-tolerant yellow birch (Betula alleghaniensis Britton) and shade-tolerant sugar maple (Acer saccharum Marsh.) and beech (Fagus grandifolia Ehrh.) growing in gaps and under a closed canopy in a sugar maple stand at Duchesnay, Que. All three species had a higher photosyntheti...

The sooty beech scale insect (Ultracoelostoma sp.) (Hemiptera: Margarodidae) exhibits a highly patchy distribution at local and regional scales. A major factor driving this common distributional phenomenon in other phloem-feeding insects is aggregation and local adaptation. The aim of this study was to determine if Ultracoelostoma was locally adapted to its natal host trees, by contrasting the ...

the incorporation of boehmite nano-particles and its effects on the mechanical properties and bond strength of an experimental dental adhesive were studied.an adhesive solution containing ethanol, bis-gma, tmptma, hema and photo-initiator system (camphorquinone and dmaema) was prepared. silanized boehmite nano-particles were incorporated into the adhesive in different concentrations of 0, 0.2, ...

Wood and wood-based materials are widely used in the construction industry world. The sustainable renewable nature of wood is seen as an important advantage contrast to non-renewable resources such aluminum, steel, concrete, plastic. In order protect advantages eliminate / reduce its disadvantages, plywood, particle board, fiber LVL, CLT, plastic composites etc. new engineering products produce...

in this research, the influence of adding micro- and nano- sized calcium carbonate powders to nylon-66 was investigated. mechanical properties of micro and nano- composites, including tensile strength, elongation, and young’s modulus, before and after ageing, were determined and analyzed. for this purpose, micro- and nano-sized caco3 particles were used as fillers to prepare micro-composites (c...

This study investigates the correlations among the tensile strength, mineral composition, and textural features of twenty-ninesandstones from Kouzestan province. The regression analyses as well as artificial neural network (ANN) are also applied to evaluatethe correlations. The results of simple regression analyses show no correlation between mineralogical features and tensile strength.However,...