Introduction: This study was designed to examine the effects of addition of the combination of polymerized polymethyl methacrylate (PMMA) and zirconia (ZrO2) particles to heat cure PMMA resin on impact strength, surface hardness, and roughness. Methods: The 70% (w/w) of polymerized PMMA powder (particle size: 0.70mm) was mixed with 30% (w/w) of zirconia powder (ZrO2) (1mm) to produce PMMA-ZrO2 filler. Ninety acrylic specimens created were divided into three groups containing 0% wt (Control group), 2% wt, and 4% wt, PMMA-ZrO2 filler. Ten specimens were used for impact strength, surface hardness and roughness test, blindly. Data were analyzed via oneway ANOVA and the Tukey post hoc test using R 3.6.3. Results: There was statistically significant difference among study groups regarding surface hardness and roughness (p < 0.001). Yet, nonsignificant difference was found on the subject of impact strength (p=0.33). Post hoc test showed statistically significant difference for all pairwise comparisons as regards surface hardness and roughness (p < 0.05). Conclusion: The incorporation of PMMA-ZrO2 filler did not improve impact strength (resistance during an unexpected blows or dropping). Yet, increased surface roughness and hardness, concentration-dependently.
Artificial intelligence (AI) offers significant benefits to biomedical research and academic writing. Nevertheless, using AI-powered writing aid tools has prompted worries about excessive dependence on these tools and their possible influence on writing proficiency. The current study aimed to explore the academic staff’s perspectives on the impact of AI on academic writing. This qualitative study incorporated in-person interviews with academic faculty members. The interviews were conducted in a semi-structured manner, using a predetermined interview guide consisting of open-ended questions. The interviews were done in person with the participants from May to November 2023. The data was analyzed using thematic analysis. Ten academics aged
... Show MoreBackground: Recently increasing number of people are using mouthwashes for general and oral care while the primary appeal of a mouthwash is an aid to breath freshness and cleansing the mouth, the majority of mouthwashes also claim to have antiseptic properties. The aim of this study is to determine the antimicrobial effectiveness of eight types of mouthwashes against Streptococcus mutans, Staphylococcus aureus and Candida albicans in vitro. Materials and methods: Agar diffusion technique was used to evaluate the antimicrobial activity of eight types of mouthwashes against Streptococcus mutans, Staphylococcus aureus and Candida albicans isolated from the oral cavities of patients attending dental clinics at college of dentistry - Baghdad Uni
... Show MoreBackground: The elimination of the microorganisms from the root canal systems, an important step for the successful root canal treatment. This study was conducted to evaluate the antibacterial effectiveness of the photoactivated disinfection by using the toluidine blue O and a low- energy light emitting diode (LED) lamp . Materials and method: Sixty single rooted extracted teeth were decoronated, instrumented, irrigated, sealed at the apex and contaminated with endodontic anaerobic bacteria for 7 days to form biofilms in prepared root canals. Group I. Twelve teeth were medicated by photosensitizer (toluidine blue O) solution activated by diode lamp (FotoSan; CMS Dental, Copenhagen, Denmark).Group II. Twelve teeth were medicated by the tricr
... Show MoreMan has a great role in the development of society in all fields, and therefore the human thought played a great role in its continuous pursuit and insight into the social classes that differ in their privileges, which makes the members of society not reconcile because of that disparity that is not based on human principles, so one class exploits another, and this is what stopped me Rather, it prompted me to choose the topic (class and its impact on society) in order to show the impact of classes on each other negatively and positively, so I work to avoid the first with the recommendations I put forward and offer guidance, and strengthen the second, and after this topic of necessity in a place because of the imbalance and promise of appr
... Show MoreFire is the most sever environmental condition affecting on concrete structures, thus investigating for fire safet, IJSR, Call for Papers, Online Journal
Fire is the most sever environmental condition affecting on concrete structures, thus investigating for fire safety in structural concrete is important for building construction. The slow heat transfer and strength loss enables concrete to be effective for fire resistance. Concrete structures withstand when exposed to fire according to: their thermal properties, rate of heating, characteristic properties of concrete mixes and their composition and on the duration of fire, and concerned as thermal property with other factors such as loss of mass which affected by aggregate type, moisture content, and composition of concrete mix. The present research goal is to study the effect of rising temperature on the compressive strength of the rea
... Show MorePurpose – measure the relationship between operation management strategies as an independent variable on the customer's delight as an approved variable.
Design/methodology/approach – The research sample vocabulary included sales representatives and customers of the researched markets at a rate of (100%). The recovery rate is (95) Customers and (95) delegates for the products for the factory in neighbourhood (Banooks and Karrada ) regions were randomly chosen from an open community in these two residential areas. Statistical methods were used (arithmetic media, standard deviations, t-test, correlation coefficient (Horst), simple regression analysis).
Findings – The people in charge of the factory management nee
... Show MoreThe research aims to a statement of specificity of the Controller of (academic achievement, specialty, job title, length of service, Gender) and its impact on performance, Through a proposed appraisal form includes three main axes and each axis including several specialized elements in the supervisory work in form (check list). as is the importance of research to enable officials of oversight bodies financial identify and diagnose performance Controller through what has this observer of the process of scientific properties when performing supervisory work. Be summarized problem of the research that the lack of regulatory institution with the Controller interesting in terms of the necessary characteristics and requirements and inv
... Show MoreThis study aims to find the effect of water-cement ratio on the compressive strength of concrete by using ultrasonic pulse velocity test (UPVT). Over 230 standard cube specimens were used in this study, with dimensions of 150mm, and concrete cubes were cured in water at 20 °C. Also, the specimens used in the study were made of concrete with varied water-cement ratio contents from 0.48 to 0.59. The specimens were taken from Diyarbakir-Turkey concrete centers and tested at the structure and material science lab, civil engineering, faculty of engineering from Dicle University. The UPV measurement and compressive strength tests were carried out at the concrete age of 28 days. Their UPV and compressive strength ranged
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