Background: The accuracy of fitness of any dental casting is imperative for the success of any prosthodontic treatment. From the time that dental casting was first introduced, efforts have been made to produce more accurate and better fitted castings with minimal marginal discrepancy. The aim of this in vitro study was to evaluate the effects of three different investing and burnout techniques on the vertical marginal discrepancies ofceramometalcopings invested with two types of phosphate- bonded investments. Materials and methods: Sixty wax patterns were fabricated on a standardized prepared brass die representing an upper central incisor by the aid of a custom-made split mold. Three different investing and burnout techniques were applied for an Iraqi investment and a commercial type; Group I:Ring investing with conventional burnout technique (RC);Group II: Ringless investing with conventional burnout technique (RLC);Group III: Ring investing with accelerated burnout technique (RA).Twenty wax patterns of each group were divided into two subgroups according to the type of investment material used (10 for each subgroup) represented as (B) for the BellaStar XL and (W) for the WYMvest investments. Complete castings were finished and seated on the metal die. The accuracy of fit of each coping was determined by measuring the vertical marginal discrepancies between the finish line on the metal die and the margins of each coping at four specific reference points on the labial, mesial, palatal, and distal aspects of the die by the aid of a light microscope supplied with a digital camera.The arithmetic mean of each three records was computed and regarded as the amount of the marginal discrepancy of each coping and was used as a unit for the statistical analysis. Results: Mean marginal accuracy for W(RLC)was found to be the least (13.839+4.5724 um) while the highest mean value related to B(RLC) (29.033+2.102 um). In general, ANOVA test showed significant results among the mean values of the Binvestment subgroups while LSD test showed non-significance between the (RA) and both the (RC) and (RLC) subgroups. On the other hand, significance was present between the (RLC) and (RA)of the Winvestment subgroups while non-significance was located between the (RC) and both the (RLC) and (RA) subgroups. Comparing similar subgroups of the two tested investments, the Student's t-test showed non-significance between the (RC) subgroups while high significance was located between the (RLC) and (RA) subgroups respectively.Concerning the vertical marginal discrepancy of the copings, applying the (RC) technique for both investments caused non-statistical significance between the labial, mesial, palatal, and distal aspects.The (RLC) technique caused high significance between the four aspects, while the (RA) technique caused non-significance between the labial aspect only and the others. Conclusion: The Iraqi investment generally produced less vertical marginal discrepancies (using the three different investing and burn-out techniques) than the commercial investment.In order to achieve a better marginal fit, it seems that ceramometalcopings invested with the commercial investment tested are better be cast using the conventional ring investing and burnout technique.
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Background: The incisive canal is an anatomical structure with an important location in the anterior maxilla, analyzing this canal and its relation to the bone anterior to the canal is necessary during dental implant. Aim of this study is evaluated effect of gender, age and tooth loss in area of maxillary central incisors teeth on the dimensions of incisive canal and buccal bone anterior to the canal using spiral computed tomography. Materials and Methods: Sample consists of prospective study for 156 subjects for both gender, they divided into two groups, 120 dentate group (60 male and 60 female) with age ranging from (20-70) and 36 edentate group (with missing maxillary central incisors) (18 male and 18 female) with age ranging from (50-70
... Show MorePhotocatalytic degradation of methylene blue was studied using CdS and ZnS as catalyst. The photocatalytic activity of the specimen was studied by exposing to UV-radiation. The result shows that the degradation efficiency of the dye for CdS micro-particles was 92% after 7 hours and for ZnS micro-particles was 88.29% for the same time interval.
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One of the most common procedures in oral surgery is the removal of impacted mandibular third molars, often followed by pain, swelling, alveolitis, and trismus. Purpose. To compare the outcomes of the intrasocket application of 1% hyaluronic acid oral gel (HA) and advanced platelet-rich fibrin (A-PRF) on the expected postoperative complications, pain, swelling, and trismus follow the surgical extraction of the impacted mandibular third molar. Material and Methods. A randomized controlled trial was conducted at the Oral and Maxillofacial Surgery Unit, Dental Teaching Hospital. Healthy patients who required surgical removal of the impacted mandibular third molar were divided randomly into three groups. The extraction site of the group
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KE Sharquie, JR Al-Rawi, AA Noaimi, MM Jabir, Iraqi Postgraduate Medical Journal, 2009
S Khalifa E, AR Jamal R, N Adil A, J Munqithe M…, 2009
Complexes of the Cr(III), Fe(III), Rh(III), Ru (III), Mo hexagonal valence and Co(II) were prepared using the azo dye 1,1'-(1,3-phenylene bis(diazene-2,1-diyl))bis(2,4,6-trihydroxy-3,1-phenylene))bis(ethan-1-one), which was prepared newly from diazonium salt with 2,4,6-trihydroxyacetophenone, after isolation. The compounds were characterized using proton and carbon nuclear magnetic resonance of the ligand and fine elemental analysis, infrared, ultraviolet-visible, mass measurement, thermogravimetric analysis, differential thermal scanning, metal percentage determination, chlorine content determination, magnetic susceptibility, and molar conductivity. The results showed that the tetra coordinated anionic bond, when linked to metal ions via t
... Show MoreThe United States has stood by Iraq and supported militarily and morally, but the relationship did not quickly be strained again before August 1990, when the oldest former political system in Iraq after Iraqi troops entered the territory of Kuwait, the United States stood beside Kuwait because the two parties link military ties opted States United to support the Kuwaiti side relying on the resolutions passed by the UN security Council, the United States and found in this issue right opportunity to execute the mechanics of meddling in Iraqi affairs and the various means of political, economic, military, and methods for dealing with Iraq, especially after finding the impediment standing in front of the implementation of its goals The strat
... Show MoreThis research aims to address the most recent international standard in the field of insurance contracts, the International Financial Reporting Standard (IFRS17) and the theoretical framework of the standard in addition to the most important characteristics of the standard (IFRS17), as well as to identify the paragraphs of the modern standard, with the challenges its application in general and the use of the approach (inputs - operations - outputs) to present the challenges of its application in the Iraqi environment and specifically in the environment of Iraqi insurance sector companies (government), the research is based on the main premise that the identification of the requirements for the application of the International Fin
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