Background Obstructing dentinal tubules is a valuable approach for managing dentin hypersensitivity. Although various agents promote dentin remineralization, direct comparisons between theobromine, bioactive glass (BAG), and nano-hydroxyapatite (Nano-HAP) under simulated oral conditions remain limited. To fill this gap, this in vitro study aimed to evaluate and compare the effectiveness of these three treatments on exposed cervical dentin. The assessment focused on their chemical, morphological, and mechanical effects on dentin. Materials and methods Forty-eight human dentin slabs were obtained from the cervical portions of twelve sound premolar teeth. Baseline Raman spectroscopy and VMH tests were done to exclude outliers. All specimens were treated with 6 % citric acid (pH 2.0) for 2 min to remove the smear layer. They randomly assigned to four groups (n = 12): artificial saliva (AS), theobromine, BAG, and Nano-HAP. Evaluations were conducted using Raman spectroscopy (phosphate peak intensity at 960cm−1), Vickers microhardness testing (VMH), and morphological assessment under scanning electron microscopy (SEM). Results Theobromine, BAG, and nano-HAP groups demonstrated a statistically significant increase in Raman phosphate peak intensity (960cm−1) and Vickers microhardness values (p < 0.05), indicating surface remineralization. In contrast, the artificial saliva group exhibited a significant decrease in phosphate peak intensity and microhardness values (p < 0.05). Conclusion All tested agents significantly enhanced the Raman phosphate peaks and microhardness values compared to the control. Nano-HAP showed the highest potential for promoting the remineralization of exposed dentin surfaces. Within the study's limitations, it can be concluded that theobromine, BAG, and nano-HAP are effective in occluding dentinal tubules.
Previous experimental studies have suggested that hot mixed asphalt (HMA) concrete using hydrated lime (HL) to partially replace the conventional limestone dust filler at 2.5% by the total weight of all aggregates showed an optimum improvement on several key mechanical properties, fatigue life span and moisture susceptibility. However, so far, the knowledge of the thermal response of the modified asphalt concrete and thermal influence on the durability of the pavement constructed are still relatively limited but important to inform pavement design. This paper, at first, reports an experimental study of the tensile fatigue life of HMA concrete mixes designed for wearing layer application. Tests were conducted under three different temperatur
... Show MoreBackground: Nanotechnology represents a new science that promises to provide a broad range of uses and improved technologies for biological and biomedical applications. One of the reasons behind the intense interest is that nanotechnology permits synthesis of materials that have structure is less than 100 nanometers. The present work revealed the effect of zinc oxide nanoparticles (ZnO NPs) on Streptococcus mutans of Human Saliva in comparison to de-ionized water. Materials and methods: Streptococcus mutans were isolated from saliva of forty eight volunteers of both sexes their age range between 18-22 years and then purified and diagnosed according to morphological characteristic and biochemical tests. Different concentrations of ZnO NPs w
... Show MoreFrictional resistance occurs whenever sliding happens, negatively impacting treatment outcomes and duration. It is a clinical challenge and must be dealt with efficiently to achieve the best orthodontic results. Aims of this study: compare and evaluate the static frictional forces under the wet condition to mimic the oral environment produced by using a polycrystalline ceramic bracket, monocrystalline ceramic bracket, 0.014 of an inch nickel-titanium (Rhodium coated archwires, and ilusio aesthetic archwires), and 0.019 x 0.025 of an inch stainless steel (Rhodium coated archwires, and ilusio aesthetic archwires). Ninety-six aesthetic brackets (48 monocrystalline and 48 polycrystalline brackets) were used and stored in different incub
... Show MoreThe research study focuses on the efficient and accurate detection and determination of cobalt ions. The detection method involves the formation of brilliant green aggregates with calcium hexacyanoferrate in the presence of nitric acid. (Nagham-four sources of white snow light-emitting diodes arranged in three rows corresponding to three detectors) (The NAG-4SX3-3D Analyzer is an optical, chemical, electronic, and detection tool that receives a cumulative signal (no amplification is required). The total distance travelled is 760 mm with regard to YZ(mV) - tsec (dmm). It was selected for its precise calculation of the energy transducer profile. The linear range for measuring cobalt (II) ions is 0.05 to 20 mM. For concentrations of 5
... Show MoreApical meristems, lateral buds, anthers of immature flowers and immature embryos of chickpea ( Cicer arietinum L.) were cultured on MS media with different growth regulators and incubated for 6 weeks at 25-27?C with 16 hrs photoperiod for callus initiation. Results indicated that 1 and 0.1 mg/l of 2,4-D and BA were suitable for callus initiation when apical meristems and lateral buds were used. While 2 and 0.5 mg/l of both growth regulators were essential for immature embryos. It was noticed that using chickpea anthers of the MS medium must contain 1mg/l 2ip and 0.5 mg/l IAA. However, MS medium supplemented with 1-3 mg/l of BA and 2,4-D respectively was good for callus initiation from lateral buds, anther and immature embryos.
... Show MoreBackground. Aneurysms of the distal anterior cerebral artery (DACA) are uncommon; they often form near the pericallosal-callosomarginal junction and are typically small. To our knowledge, giant DACA aneurysms developing from the more distant parts of the anterior cerebral artery (ACA), A4-5, have been described only once in the literature. Case description. A 66-year-old gentleman reported with a brief loss of consciousness followed by weakness in his right lower leg. The patient was admitted with a Glasgow Coma Score (GCS) of 15. A computed tomography (CT) scan of the head revealed a left hyperdense mass in the frontal parasagittal supracallosal region. Contrast MRI revealed a heterogeneously enhancing mass measuring 35x30x25 mm. C
... Show MoreIn this study, polymeric coating was developed by incorporating nano graphene in the polymer blend with applications to oil storage tanks. The oil storage tanks samples were brought from the oil Pipeline Company / Doura refinery in Baghdad. The coating polymer was formed with a blend (epoxy resin and repcoat ZR). The proportion of mixing the mixture was 3:1:1 epoxy resin 21.06 gm: repcoat ZR 10.53 gm: hardener 10.53 gm. The blend/graphene was prepared using in stui-polymerization method with different weight percentage 1, 3, 5, and 7 wt % added to blend. The resulting solution was put in a glass tube on a magnetic stirrer for one hour at a temperature of 40 °C. The result of contact angle and water absorption the best ratio of 3wt
... Show MoreDrawing upon the recent theoretical framework of Burkean concept of identification (ID), the current study aims at probing the interaction of content and form in two letters penned by Iran’s Supreme Leader and addressed to the Youth on Jan. and Nov. 2015. To this end, the study seeks (i) to determine a role ID takes in the conveyance of intended assumptions to the targeted readers; and (ii) to observe if the writer’s objectives, i.e. to identify himself with the readers and to realize his politically-religiously-infused creeds, result in success or failure; moreover, (iii) it seeks to determine how he achieved his end to attenuate the impacts of blazing inferno of Islamophobia and anti-Islam sentiments in his addressees. The who
... Show MoreBackground: Aesthetic archwires are used to overcome the aesthetic problems of stainless steel wires but the color of the coating layer can be changed with time when exposed to oral environments. The aim of this study was to evaluate the degree of color change of different aesthetic archwires from different companies under different coloring solutions. Materials and Methods: One hundred fifty samples of coated archwires from three companies (Highland, G&H and Dany) were immersed in 5 solutions (artificial saliva, turmeric, tea, coffee and Miranda) to evaluate the degree of color changes after 7, 14 and 21 days using visible spectrophotometer. Data were collected and analyzed using one way ANOVA and post hoc Tukey’s tests. Resu
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