This study compared in vitro the microleakage of a new low shrink silorane-based posterior composite (Filtek™ P90) and two methacrylate-based composites: a packable posterior composite (Filtek™ P60) and a nanofill composite (Filtek™ Supreme XT) through dye penetration test. Thirty sound human upper premolars were used in this study. Standardized class V cavities were prepared at the buccal surface of each tooth. The teeth were then divided into three groups of ten teeth each: (Group 1: restored with Filtek™ P90, Group 2: restored with Filtek™ P60, and Group 3: restored with Filtek™ Supreme XT). Each composite system was used according to the manufacturer's instructions with their corresponding adhesive systems. The teeth were then thermocycled, immersed in 1% methylene blue dye for 24 hours at room temperature, embedded in auto-polymerizing acrylic resin and sectioned longitudinally bucco-lingually. Microleakage was evaluated by assessing the linear dye penetration at the tooth/restoration interface occlusally and gingivally. The highest microleakage score occlusally or gingivally was recorded and the results were analyzed statistically using SPSS version 13. The results of this study showed that the silorane-based posterior composite Filtek™ P90 showed significantly less microleakage than the methacrylate-based packable composite (Filtek™ P60) and the nano-filled composite (Filtek™ Supreme XT) when the tooth-restoration interface is located in enamel.
The anatomic characteristics of the leaves of 22 taxa of Stachys L. representing seven of the currently recognized sections distributed in northern Iraq, were examined. The study did not found any variations in the characteristics of the stomata system of the leaves.Therewere variations with a good taxonomic value in other anatomic characteristics.Thevariations in characters of the mesophyll tissue in S.kurdica var.brevidens Bom ex Bhattacharjeewas bifacial but in S.kurdica var.kurdica Boiss. & Hohen.was unifacial .The study also found that the taxa S.benthamiana Bioss., S.lanigera (Bornm.) Rech.f. andS.kotscyi Bioss. with 3 vascular bundles in the middle vein while the taxa S.ballotiformis Vatke., S.megalodonta Hausskn. &Bornm.exP.H.Davis
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The anatomic characteristics of the leaves of 22 taxa of Stachys L. representing seven of the currently recognized sections distributed in northern Iraq, were examined. The study did not found any variations in the characteristics of the stomata system of the leaves.Therewere variations with a good taxonomic value in other anatomic characteristics.Thevariations in characters of the mesophyll tissue in S.kurdica var.brevidens Bom ex Bhattacharjeewas bifacial but in S.kurdica var.kurdica Boiss. & Hohen.was unifacial .The study also found that the taxa S.benthamiana Bioss., S.lanigera (Bornm.) Rech.f. andS.kotscyi Bioss. with 3 vascular bundles in the middle vein while the taxa S.ballotiformis Vatke., S.megalodonta Hausskn. &Bo
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Background: Semen contamination is a detrimental factor in decreasing fertility. Seasonal changes may affect the contamination, too. Objectives: This study was designed to detect semen contamination in ovine and caprine during different seasons. Methods: Six fully mature male sheep and goats were subjected to electro-ejaculator collection twice monthly from February 1, 2022, to January 31, 2023 (Spring, February 1, 2022-April 30, 2022; Summer, May 1, 2022, July 31, 2022; Autumn August 1, 2022, October 31, 2022; Winter November 1, 2022, January 31, 2023), for studying the seasonal effect. A total of 288 semen samples were collected from both species (36 samples from each per season). All samples were subjected to bacterial isolatio
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Several amine liquid selective electrodes were prepared based on
two active materials, phenol sulfonic acid and l ,2-dihydroxy-3,5- disulfonic acid disodium salt with several plasticizers, di-n-butyl phthalate(ORPH), tri-n-butyl phosphate (TBP) and a-nitro phenyl octyl ether (NPOE). Electrode parameters were studied including, concentration range, detection limit, slope, life time, response time and
... Show MoreCreep testing is an important part of the characterization of composite materials. It is crucial to determine long-term deflection levels and time-to-failure for these advanced materials. The work is carried out to investigate creep behavior on isotropic composite columns. Isotropy property was obtained by making a new type of composite made from a paste of particles of carbon fibers mixed with epoxy resin and E-glass particles mixed with epoxy resin. This type of manufacturing process can be called the compression mold composite or the squeeze mold composite. Experimental work was carried out with changing the fiber concentration (30, 40 and 50% mass fraction), cross section shape, and type of composite. The creep results showed that th
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Background: The main aim of the present study is to qualify and quantify voids formation of root canals obturated with GuttaCore (GC) and experimental Hydroxyapatite polyethylene (HA/PE) as new carrier-based root canal fillings by using micro computed tomography scan. Materials and methods: In the present study, eight straight single-rooted human permanent premolar teeth are selected and disinfected, then stored in distilled water. The teeth decoronated leaving a root length of 12mm each. The root canals instrumented by using crown down technique and the apical diameter of the root canal prepared to a size # 30/0.04 for achieving standardized measurements. A 5mL of 17% EDTA used to remove the smear layer followed by 5mL of 2.5% NaOCl and r
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