Background: The aim of this study was to evaluate and compare the apical microleakage around retrograde cavities prepared with ultrasonic technique and filled with (Biodentine™) Materials and methods: 40 extracted single rooted human permanent maxillary teeth with mature apices were selected. The roots were prepared chemo-mechanically using k-files with crown-down technique and then obturated with lateral condensation gutta-percha technique. Teeth were divided into four main groups according to the cavity preparation method either manual or ultrasonic technique: Group A (n=10): A class I retrograde cavity at root end was prepared with traditional handpeice equipped and placement of Biodentine with manual condensation. Group B (n=10): A class I retrograde cavity at root end was prepared with Piezoelectric ultrasonic device equipped with ultrasonic tip with only manual compaction of the material. Group C (n=10): traditional handpeice and placement of Biodentine using both manual compaction and 5 second ultrasonic activation. Group D (n=10): Piezoelectric ultrasonic device and placement of Biodentine with both manual compaction and 5 second ultrasonic compaction. The teeth were immersed in 1% aqueous Methylene blue dye for 72 hr. Then they were sectioned longitudinally with a diamond disc and the depth of dye penetration was examined under high magnification 20X. Results: Statistical analysis showed a highly significant difference in microleakage among the tested groups in which Piezoelectric technique has proved superiority in retrograde cavity preparation and compaction of Biodentin when dye penetration scores were compared. So microleakage was highest with cavities prepared with handpeice and manual application of retrograde material group A (2.73±0.39) followed by microprepared cavities group C (1.86±0.16), and it was lowest with ultrasonically-prepared cavities group B (1.09±0.28) and group D (0.26±0.19). Conclusion: ultrasonic preparation produced significantly less microleakage than conventional method. Also less microleakage was observed with ultrasonic compaction of Biodentin when compared with conventional method of compaction.
Statement of the Problem. The use of orthodontic fixed appliances may adversely affect oral health leading to demineralizing lesions and the development of gingival problems. Aims of the Study. The study aimed to coat orthodontic archwires with chlorhexidine hexametaphosphate nanoparticles (CHX-HMP NPs) and to evaluate the elusion of CHX from CHX-HMP NPs. Materials and Methods. A solution of CHX-HMP nanoparticles with an overall concentration of 5 mM for both CHX and HMP was prepared, characterized (using atomic force microscope and Fourier transformation infrared spectroscopy), and used to coat orthodontic stainless steel (SSW) and NiTi archwires (NiTiW). The coated segments were characterized (using scanning electron microscopy
... Show MoreBackground: periodontitis is a chronic inflammatory disease causing destruction of the tooth supporting structures, initiated by dental plaque and modified by environmental and genetic risk factors. Cyclooxygenase-2 (COX-2) enzyme is responsible for the production of prostaglandin E2, an important mediator in the chronic periodontitis (CP) pathogenesis. Polymorphisms in COX-2 gene have linked to CP in different populations. Aim: To study the association between Cyclooxygenase-2 single nucleotide polymorphism rs689466 (-1195A/G SNP) and chronic periodontitis in a sample of Iraqi population. Methods: One hundred Iraqi subjects divided into two groups: case group consisted of 70 CP patient (35 males and 35 females) with age range 30-55 year
... Show MoreThe physical, mechanical, electrical and thermal properties containing (Viscosity, curing, adhesion force, Tensile strength, Lap shear strength, Resistively, Electrical conductivity and flammability) of adhesive material that prepared from Nitrocellulose reinforced with graphite particles and aluminum streat. A comparison is made between the properties of adhesive material with varying percentage of graphite powder (0%, 25%, 30%, 35%, 40%) to find out the effect of reinforcement on the adhesive material. The ability of property an electrical was studied through the measurement of conductivity a function of temperature varying. The results of comparison have clearly shown that the increasing of conten
... Show MoreObjective: This study was designed to investigate some possible therapeutic mechanisms of pentoxifylline and sildenafil in the treatment of colorectal carcinoma induced by 1, 2 dimethylhydrazines in rats. Methods: Rats were allocated into seven groups, negative control, colon cancer induced by 1,2,dimethylhydrazine, 5-fluorouracil (5-FU) (50 mg/kg)-treated, pentoxifylline (PTX) (50 mg/kg)-treated, sildenafil (0.7 mg/kg)-treated groups; the two other groups set as colon cancer induced group treated with PTX (50 mg/kg) plus 5-FU(50 mg/kg) and sildenafil (0.7 mg/kg) plus 5-FU (50 mg/kg), respectively. Results: Biochemical results revealed significant elevation of serum carcinoembryonic antigen (CEA) levels, carbohydrate19-9 antigen (CA19-9) as
... Show Moreيختبر البحث الحالي التأثيرات المشتركة للإشعاع بالموجات فوق الصوتية والمادة المانحة للهيدروجين على لزوجة النفط الخام الثقيل. تمت دراسة تأثير زمن التعرض للموجات فوق الصوتية والطاقة ودورة التشغيل ودرجة الحرارة على لزوجة النفط الخام العراقي الثقيل الذي يملك قيمة .20.32 = API كما تم فحص لزوجة عينات النفط الخام التي تم خلطها بمانح الهيدروجين (Decalin) وإخضاعها للمعالجة بالموجات فوق الصوتية في ظل الظروف المثا
... Show MoreThe current investigation examines the combined impacts of ultrasonic radiation and hydrogen donors on the viscosity of heavy crude oil. The impact of exposure time, power, duty cycle, and temperature on the viscosity of Iraqi heavy crude oil with 20.32 API was studied. Also, the viscosity of the oil samples, which were mixed with a hydrogen donor (decalin) and subjected to ultrasonic treatment under optimal conditions, was examined to evaluate the combined impact of ultrasonic radiation and hydrogen donor on the viscosity of crude oil. The viscosity experienced a decrease of 52.34% at 2 min of irradiation, 360 W ultrasonic power, 0.8 duty cycle, 35 ⁰C, and 8vol% decalin. To validate the outcomes of the experiments, asphaltene content, s
... Show MoreThis study evaluates the performance of magnetic abrasive finishing (MAF) of aluminum alloy in terms of achieving materials removal (MR). A vertical milling machine is used to perform the finishing process using a developed MAF unit that consists of an inductor made out of a 150 mm long and 20 mm diameter iron core wound with 1500 turns and 0.5 mm copper wire. The commutator and magnetic pole are attached at the top and bottom of the inductor, respectively. The required current is supplied using a DC power supply. The South Pole workpiece is a 100×50×3 mm3 plate of AA 1100 aluminum alloy, whereas the magnetic pole represented the North Pole. Pole rotational speed, applied current, and abrasive finishing time was selected as
... Show MoreFifty three hydatid cysts were collected from different hosts, sheep, goats and cattle , from many slaughterhouse in Salahadin and Baghdad , while human's hydatid cysts samples were collected from Tikrit educational hospital and Tofiqe civilian hospital patients . The study included a biochemical comparison of some hydatid cyst fluid criteria such as, glucose, total protein, pH, glutamate pyrovate transaminase enzyme (GPT) , glutamate oxaloacetate transaminase enzyme (GOT) , acid phosphatase (ACP) , Alkaline Phosphatase (ALP) , and also studied protoscolices viability,the current study showed the differences in chemical composition of hydatid cyst fluids back to host type and parasite strain .