Background: With the increasing demands for adult orthodontics, a growing need arises to bond attachments to porcelain surfaces. Optimal adhesion to porcelain surface should allow orthodontic treatment without bond failure but not jeopardize porcelain integrity after debonding.The present study was carried out to compare the shear bond strength of metal bracket bonded to porcelain surface prepared by two mechanical treatments and by using different etching systems (Hydrofluoric acid 9% and acidulated phosphate fluoride 1.23%). Materials and Methods: The samples were comprised of 60 models (28mm *15mm*28mm) of metal fused to porcelain (feldspathic porcelain). They were divided as the following: group I (control): the porcelain surface left untreated and glazed, group II (Diamond bur group): the porcelain surface was treated with fine diamond bur at speed of 350000 rpm for 20 seconds, group III (Red stone bur): the porcelain surface was treated with coarse red stone bur at speed of 8500 rpm for 20 seconds. Each group consists of 20 samples, then each group subdivided into two subgroups; one treated with acidulated phosphate fluoride 1.23% and the other subgroup treated with Hydrofluoric acid 9 % with silane coupling agent. Results: The result of this study revealed that there was very high significant difference among all tested groups and the highest shear bond strength was for diamond bur group with HFA and Silane (8.67 MPa), the 2nd highest strength was for control group with HFA and Silane (7.52 MPa), the 3rd was (7.38 MPa) in red stone bur with HFA and Silane, the least shear bond strength values were obtained for subgroups treated with acidulated phosphate fluoride gel 1.23%. Conclusions: The most reliable procedure for bonding orthodontic brackets to the porcelain surfaces is through the surface treatment combinations of mechanical roughening by using diamond bur, 9% Hydrofluoric acid and Silane coupling agent application.
This study aimed to clarify the provisions of taking the mother for breastfeeding in Islamic jurisprudence, a comparative study between doctrines of jurisprudence. The ruling on forcing the mother to breastfeed, and the ruling on taking the mother for breastfeeding while she is in the infallibility of her husband, as well as in several reactionary divorces, and the ruling on breastfeeding in several divorced divorces. On breastfeeding in infallibility Face, as well as a several divorce reactionary, and worth the fare which is in several final divorces, and after the end of the marital relationship, has been proposed a number of recommendations, including it, is recommended to teach the provisions of the mother taking the taxi on breastfe
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In the current work various types of epoxy composites were added to concrete to enhance its effectiveness as a gamma- ray shield. Four epoxy samples of (E/clay/B4C) S1, (E/Mag/B4C) S2, (EPIL) S3 and (Ep) S4 were used in a comparative study of gamma radiation attenuation properties of these shields that calculating using Mont Carlo code (MCNP-5). Adopting Win X-com software and Artificial Neural Network (ANN), µ/ρ revealed great compliance with MCNP-5. By applying (µ/ρ) output for gamma at different energies, HVL, TVL and MFP have been also estimated. ANN technique was simulated to estimate (µ/ρ) and dose rates. According to the results, µ/ρ of all epoxy samples scored higher than standard concrete. Both S2 and S3 samples having h
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The duration of the contract is a legal term first provided for in French Amendment Decree No. 131/2016, and given the increasing importance of time in contracts, we have chosen to study the legal rules governing time at the formative stage by drawing on changes in French law compared to both Iraqi and Egyptian laws. Article 1102 of French Amendment Decree No. 131/2016 stipulates that: "Everyone is free to contract or not to contract, to choose the person with whom he contracts, and to determine the content and form of the contract within the limits established by law." Contractual freedom does not permit a breach of the rules relating to public order), as well as article 1104, which provides for (contracts must be nego
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Background: Recurrent aphthous ulceration (RAU) is an inflammatory condition of unknown etiology characterized by painful recurrent (single or multiple) ulcerations of the oral mucosa. It is one of the most common and poorly understood mucosal disorders. It occurs more frequently in times of stress. Local and systemic conditions, genetic, immunologic, microbial factors, and oxidative stress may play a role in the pathogenesis of RAU. The objective of this study was to evaluate the free radical metabolism and antioxidant activity of RAU patients treated by lavender or flax oil paint.
Materials and Methods: Sixty-six RAU patients were enroll
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Background: Goiter is one of the most common conditions that affect people’s at different age groups with its effect on the metabolic status of the body through the hyper&/hypo functioning gland that may needs surgical resection. This prospective study had been conducted on 100 patient (85 females&15 males} at the specialized center for endocrinology and diabetes mellitus in Baghdad city, between Jan.2013-Oct.2014;Their ages were ranging between 11-75 years ; the median age is (40.5 years) .Objectives: define the clinic-pathological pattern of goiter in the center .Methods: This is a prospective study at the specialized center for endocrinology & diabetes in Baghdad at ALRissafa district; including 100 patients (84 f