Abstract: Objectives: To investigate the effect of temperature elevation on the bonding strength of resin cement to the zirconia ceramic using fractional CO2 laser. Background: Fractional CO2 laser is an effective surface treatment of zirconia ceramic, as it increases the bonding strength of zirconia to resin cement. Methods: Thirty sintered zirconia discs (10 mm diameter, 2 mm thickness) were prepared and divided to three groups (N=10) and five diffident pulse durations were used in each group (0.1, 0.5, 1, 5 and 10 ms). Group A was treated with 10 W power setting, group B with 20 W and group C with 30 W. During laser irradiation, temperature elevation measurement was recorded for each specimen. Luting cement was bonded to the treated zirconia surfaces and cured for 30 seconds. Shear bond strength was evaluated by a testing machine (universal) with bond failure mode determination. Results: The lowest temperature elevation measurement of the irradiated specimen which gave maximum shear bond strength was about 1.6±0.3 Ċ higher than ambient room temperature (27±0.2 ºC). Apparent micromechanical irregularities were seen in the treated samples and cracks formation with increased pulse duration and power setting were also observed. Conclusions: The temperature elevation is a vital factor in the surface roughness of zirconia ceramic with fractional CO2 laser irradiation and the lowest temperature elevation at best shear bond strength of zirconia ceramic to the resin cement is satisfied with the shorter pulse duration of 0.1 millisecond.
Background: Bimaxillary protrusion is considered as one of the most important causes to seek the orthodontic treatment to get better esthetics. This study aimed to test the effect of orthodontic treatment in improvement the facial esthetics. Materials and Methods: Ten Iraqi Arab females having bimaxillary protrusion based on Class I malocclusions treated with fixed orthodontic appliance and extraction of the maxillary and mandibular 1st permanent premolars. Pre and post-treatment facial profile photographs were taken for each patients and the effect of treatment was tested in comparison with the pre-treatment photographs by using seven angular measurements. Results: After treatment, the upper and lower lip projections were decreased signifi
... Show MoreResearch objective: This research aims to unveil how to use the method of referral in understanding the Holy Quran.
The reason for choosing the research: The one that invited me to write on this topic is the importance of the referral method, so I liked the research in it, and unveiled this wonderful Qur’anic method, so that it helps to understand the intention of God Almighty in his dear book.
The research plan: The research was divided into three topics and a conclusion.
As for the first topic, it is divided into two requirements. The first requirement deals with the definition of referral language.
In the second re
The two objectives of the current research are :-
- Uncover the views and opinions of the students of Artistic Education Department about the relation between educational novelty and its relation with visual .
- Identifying the capabilities of the students of artistic education department .
The society of the research is the fourth class students of artistic education department - College of Fine Arts ( 83 students from both sexes ) . It was chosen ( 60 ) students sample of from both sexes by the researcher in order to conduct test upon them .The researcher has adopted descr
... Show MoreA direct spectrophotometric method has been developed for the
determination of nitrite in aqueous solution. The method is based on the reaction of the nitritw ion with an acidified anline solution from diazonium cation , which is subsequently coupled ·with 4,6 - dihydroxy- 2- mercapto pyrimidine to from yellow colored and water
- soluble intense azo dye with maximum absorption at 416nm . A
graph of absorbance versus concentration shows that Bee's
... Show MoreCarbon Monoxide (CO) has a significant indirect effect on greenhouse gasses due to its ozone and carbon dioxide precursor, and its mechanism of degradation involving the hydroxyl radical (OH) which control the oxidizing ability of the tropospheric. To understand the effect of human activities on atmospheric composition, accurate estimates of the sources of atmospheric carbon monoxide (CO) are necessary. MOPITT (Measurements of Pollution in the Troposphere) is a NASA Terra satellite instrument designed to allow both Thermal-Infra-Red (TIR) and Near-Infra-Red (NIR) observations to be used to collect vertical CO profiles in the Troposphere via the concept of correlation spectroscopy. The objective of the current stu
... Show MoreBackground: Primary healthcare in Egypt has undergone significant reforms since the 1990s, including the pioneering Family Health Program (FHP). However, limited evaluation exists regarding the FHP's impact on enhancing the delivery of primary healthcare services. The primary objective of this study was to analyze and understand the efficiency and effectiveness of the FHP in altering the delivery of primary healthcare in Egypt. We aimed to outline the fundamental characteristics of the primary healthcare system, compare them between the conventional and the newly reformed FHP centers, and gauge the awareness level of these variances among key decision-makers, focusing specifically on Cairo, Egypt. Methods: This cross-sectional study employe
... Show MoreThe Yamama Formation is characterized by a wide geographic extension of southern Iraq. Microfacies analysis of this formation was studied in six wells distributed in six fields: Fayhaa, Sindbad, Siba, Zubair, Ratawi and West Qurna. This research aims to determine paleoenvironments by diagnosing biofacies and lithofacies. Miscellaneous marine fauna of foraminifera and calcareous algae, mainly green algae (dasycladacean.) and skeletal bioclasts from gastropods, pelecypods, bryozoans, sponge spicules, and echinoderms were found. Petrographic studies and well logs interpretations led to the identification of five main Microfacies ( Mudstone, Wackestone, Packestone, Grainestone and Rudstone and twelve submicrofacies (Foraminiferal-
... Show MoreRotaviruses, a major cause of gastroenteritis in children worldwide accounts for around half a million deaths annually. Vaccine against the virus has been recommended by the WHO to be involved in the national immunization program.To evaluate the genetic characterization of rotavirus among children with acute gastroenteritis in Babylon province is warranted. Children complained of diarrhea with rotavirus infection detected in their stool were involved in the study. The age range was 10 months to 60 months and with retrogradechecking of rotavirus vaccine history. Rotavirus genotypes were detected by reverse transcription-polymerase chain reaction (RT-PCR).A total number of 40 children with rotavirus gastroenteritis were used to examine the
... Show MoreTo determine the relationship between chronic hepatitis B virus and autoimmune celiac disease, seventy five patients with chronic hepatitis B virus of ages (8-70) years have been investigated and compared with 50 healthy individuals. All the studied groups were carried out to measure antiGliadin antibodies IgA and IgG by ELISA test and anti-reticulin antibodies IgA and IgG by IFAT. There were significant elevation (P<0.05) in the concentration of AGA IgA and IgG antibodies compared to control group. The prevalence of AGA antibodies IgA and IgG was 8% and 9.33% respectively. There were a highly significant differences (P<0.01) between studies groups. The prevalence of antireticulin antibodies ARA IgA and IgG was 6.67% and 4.0% respectively i
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