Background: The present study was conducted to evaluate the effects of different bleaching methods on the shear bond strength of orthodontic Sapphire brackets bonded to human premolars teeth using light cured composite resin and to determine the predominant site of bond failure. Materials and Methods: Thirty freshly extracted human premolars were selected and randomly divided into three groups (10 per group). These groups are: control (unbleached) group, hydrogen peroxide group (HP) 37.5% ; which is the in- office bleaching method group, carbamide peroxide group (CP) 16%; which is the at- home bleaching method group. After bleaching process was performed, all the teeth stored in distilled water in a sealed container at room temperature for 24 hours before bonding was initiated, then orthodontic brackets were bonded with a light cure composite resin, stored in distilled water at room temperature for another 24 hours before debonding then the brackets de-bonded and tested for shear bond strength using an Instron universal testing machine. For adhesive remnant index (ARI) the enamel surface and bracket base of each tooth were inspected under magnifying lens (20X) of a stereomicroscope. Results and Conclusions: Non-statistically significant differences of shear bond strengths were found between the control group and the bleached groups, the dental bleaching in both methods did not affect the SBS of Sapphire brackets. The mode of failure was mostly between the adhesive and the enamel and the bond failure between the bracket base and the adhesive were also observed. Keywords: Shear bond strength, tooth bleaching agents, orthodontic brackets, dental bonding.
The study aims to determine the concentrations of radon, humidity, and CO2 in residences within the Mitham Al-Tammar neighbourhood of Kufa, utilising an Airthings 2960 Wave Plus device in the living rooms of each household. The concentration of radon varied, with a minimum value of 13 ± 3.9 Bq/m3 and a maximum value of 90 ± 5.8 Bq/m3, yielding an average rate of 35.8 ± 4.889 Bq/m3. The concentrations of total VOCs in residences ranged from 69.26 ppb to 810.14 ppb, with a mean of 321.4855 ± 40.4. The humidity percentages exhibited a minimum concentration of 51.68% and a maximum of 122.97%, averaging 76.594 ± 4.298. The concentrations of volatile organic compounds and
... Show MoreBackground and Aim: The aryl hydrocarbon receptor (AhR) plays a pivotal role in spermatogenesis through its regulatory functions in redox balance and gene expression. This study aimed to investigate the effects of resveratrol (RES), a polyphenolic AhR modulator, and CH223191, a selective AhR antagonist, on male reproductive function in rats by assessing sperm quality, oxidative stress, testicular histopathology, and AhR gene expression. Materials and Methods: Forty adult male rats were randomly divided into four groups: (i) Control, (ii) dimethyl sulfoxide (vehicle), (iii) RES (100 mg/kg i.p., twice weekly), and (iv) AhR⁻ (CH223191, 10 mg/kg i.p., twice weekly), treated for 60 days. Post-treatment, sperm motility, survival, viabi
... Show MoreAbstract
Objectives: The present study designed to explore the genotoxicity through measurement of Mitotic index in bone marrow and the spleen cells, as possible mechanism of bone marrow and spleen toxicity that induced by irinotecan; and to describe the protective actions of omega 3 against irinotecan induced genotoxicity in bone marrow and the spleen of rats.
Methods: Twenty four (24) rats (Sprague-Dawley) were randomly divided into four groups: Group Ӏ, rats received single oral daily dose of distilled water (2 ml/kg) for 25 days (negative control group); Group ӀӀ (irinotecan-treated), receiv
... Show MoreBackground: Temporomandibular joint disorders refer to a group of heterogeneous pain and dysfunction conditions involving the masticatory system, reducing life quality of the sufferers. Arthrocentesis is simple and less invasive surgical procedure for the treatment of internal derangement than arthroscopy and better than other conservative procedures such as drugs, occlusal appliances and physiotherapy. The aim of the study was to evaluate the effect of arthrocentesis with injection of hyaluronic acid in the treatment of internal derangement of temporomandibular joint for the restoration of its function, reducing pain and preventing further deterioration of the temporomandibular joint dysfunction. Materials and methods: This study was perfo
... Show MoreThe selective information broadcasting service is one of the important services in libraries and information centers, as it is the link between the source and the beneficiary and between related sources, as it links similar sources through keywords and then sends them to beneficiaries, which contributes to reducing the time and effort spent by beneficiaries in obtaining sources or information. Therefore, the application of this service is an important matter and gives a positive indicator in the progress of the library towards the integration of its services. From this standpoint, this research came to answer some questions, including: 1. What are the outlets for beneficiaries (the research community) in obtaining information sources? 2. Wh
... Show MorePurpose: To contribute to the development of an appropriate program for the management of medical waste based on clear-cut principles in order to reach the overall goal of improving the public health and environment of the population in our country.
Design / Approach / Introduction: The research is based on the analytical descriptive approach as a method of study in the field of data collection using a check list and analysis of the data through the use of some statistical treatments.
Results: The need is to establish a medical waste management in hospitals and follow international standards in all stages of waste management from sorting, collection, transportation and treat
... Show MoreThe research is exposed to an important issue, related to communication obstacles that prevent the media message contained in cultural topics published in local newspapers to reach the hands of the readers; or related to lack of awareness of aspects of that media message, Because it contains immersed vocabulary in elitism where, sometime, the average reader of the newspaper of medium-sized educated, and even the academic reader are unable to decode it and understand its significance.
After determining the problem of the study and the tools that the researcher wants to use to accomplish his research, a sample of students of college of Arts at the University of Baghdad was selected. As they are clo
... Show MoreThe role of the climate in the development of the performance of the administrative bodies of sports clubs
Abstract:
The purpose of this research is measuring relationship level and impact between Organizational Factors and their Dimensions (Leadership, Organizational Structure, Organizational Culture), and Talent Management Strategies (Talent Recruitment,Talent performance management, Talent Development, Talent Retention ). it was relied on the Questionnaire form as a basic instrument in collecting the Data by using (Likert) instrument ,which was distributed on the research Sample which number was (100) individual included (Managers of schools, assistants (scientific and Administration ) and teachers in Four schools of Talents in Iraq (Baghdad , AL-Nagaf , AL-Basra, Mesan). All fo
... Show More