Objective To evaluate recently developed acidic calcium-phosphate (CaP) pastes as conservative enamel-conditioning systems for bracket bonding and investigate their effects on the shear bond strength, adhesive residues, and enamel damage in comparison to a conventional 37 % phosphoric acid (PA) gel. Materials and methods Two experimental etchant pastes consisting of hydroxyapatite and monocalcium phosphate monohydrate were prepared by mixing them with 37 % and 10 % PA solutions, respectively. These were characterized using X-ray diffraction. Metal brackets were bonded to 90 freshly extracted human premolars and assigned to three groups, depending on etchant type: 37 % PA-gel (control) and the two experimental (HPA and MPA) pastes. Shear bond strengths (SBS), adhesive remnant index scores, and enamel damage for the three groups were compared at 24 h water storage and after 5000 thermocycles. Enamel etch pattern, surface damage, and CaP precipitation were evaluated through FE-SEM. Surface Vickers micro-hardness (VHN) following etching procedures was compared to the unetched enamel surface. Results HPA and MPA pastes yielded significantly lower SBS values than 37 % PA-gel (p < 0.001), induced a milder etch pattern, unblemished enamel surfaces and CaP re-precipitation with no or minimal adhesive residues post-bracket debonding as compared to 37 % PA-gel. Moreover, the HPA paste-etched enamel revealed the highest (p < 0.001) micro-hardness value (232 VHN). Conclusions Enamel conditioning using the CaP pastes, particularly the HPA, may evoke CaP re-precipitation and cause minimal enamel damage, with greater efficiency at bracket debonding/enamel cleaning procedures. Furthermore, it yields low adhesive residues and potentially adequate bond strength for clinical performance in comparison to conventional PA gel. Clinical Significance Enamel etching with the developed paste prior to orthodontic bonding might lessen the development of white spot lesions during treatment, with the potential of reducing the prolonged chair time for clean-up and polishing usually required whenever PA is used.
The deficiency in the nurse staff in the health organizations consider an important problem that must be studied and solved basically , not only because it affect on the health organization and it's strategic goals , but also it affect the human being and it's health which can't be substituted with anything or delayed in it's treatment ,This research aims to necessary for health organizations to strategically help in maintaining the nurse staff and to keep that in it's strategic orientation and it's mission , moreover , the health organizations must study the reality of the nurse in the health organizations and know the causes beyond leaving the nurse staff the nurse job , and then remove
... Show MoreOne of the most popular and legally recognized behavioral biometrics is the individual's signature, which is used for verification and identification in many different industries, including business, law, and finance. The purpose of the signature verification method is to distinguish genuine from forged signatures, a task complicated by cultural and personal variances. Analysis, comparison, and evaluation of handwriting features are performed in forensic handwriting analysis to establish whether or not the writing was produced by a known writer. In contrast to other languages, Arabic makes use of diacritics, ligatures, and overlaps that are unique to it. Due to the absence of dynamic information in the writing of Arabic signatures,
... Show MoreSignature verification involves vague situations in which a signature could resemble many reference samples or might differ because of handwriting variances. By presenting the features and similarity score of signatures from the matching algorithm as fuzzy sets and capturing the degrees of membership, non-membership, and indeterminacy, a neutrosophic engine can significantly contribute to signature verification by addressing the inherent uncertainties and ambiguities present in signatures. But type-1 neutrosophic logic gives these membership functions fixed values, which could not adequately capture the various degrees of uncertainty in the characteristics of signatures. Type-1 neutrosophic representation is also unable to adjust to various
... Show MoreBackground: The microorganisms can impend the life of health care professional and particularly the dental practitioners. They can be transmitted by different ways like airborne and droplet transmission. The current study was carried out to identify whether the arch wires that received from the manufactures are free from microbial contamination and to determine the bacterial species attached to the arch wires. Materials and Methods: This study involved eighty samples, consisted of two types of arch wires (nitinol and stainless-steel) from four companies (3M, G&H, Jiscop, OrthoTechnology). These wires inserted in a plane tube that contains 10 -ml of (Tris [tris(hydroxymethyl)aminomethane] and EDTA (ethylenediaminetetraacetic acid) tri
... Show More: In this study, a linear synchronous machine is compared with a linear transverse flux machine. Both machines have been designed and built with the intention of being used as the power take off in a free piston engine. As both topologies are cylindrical, it is not possible to construct either using just flat laminations and so alternative methods are described and demonstrated. Despite the difference in topology and specification, the machines are compared on a common base in terms of rated force and suitability for use as a generator. Experience gained during the manufacture of two prototypes is described.
Objectives: To assess the qualifications and performance of newly graduated pharmacists and explore factors that affect their performance in public hospitals. Methods: This qualitative study included face-to-face, semi-structured interviews with hospital practitioner pharmacists. It was conducted between March and May 2023 in Kerbala province, Iraq. The participating pharmacists were selected purposefully because they had three or more years of work experience at governmental hospitals. The audio-recording interviews were transcribed. Thematic analyses were used to generate themes and subthemes from the interviews. Results: Twenty-seven hospital pharmacists participated in this study. The study found that there are several factors t
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