Abstract Background: Crown lengthening is a surgical procedure that apically positions the gingival edge and/or removes supporting bone in order to increase the amount of supra gingival tooth structure for restorative or cosmetic purposes.
The objective of the study: The purpose of this study was to evaluate the efficacy of the 940nm diode laser in esthetic crown lengthening surgery through clinical observations, patient questionnaires, clinical photographs, and gingival healing following gingival operations. Material and methods: In this randomized clinical trial, 16 patients (11 females and 5 males) had their crowns surgically lengthened using a diode laser (940 nm) in continuou
... Show MoreThis work was carried out to investigate the shrinkage properties of insulator ceramic body, and the effect of changing the ratio of concentration of electrolyte solution on these properties. The electrical insulator body was prepared by using Iraqi local materials. These are :- kaolin Duakhla, Arudhuma Sand glass, and potash feldspar with weight percentage (45%, 25%,and 30%) respectively. The processes of milling, classification, mixing, forming and firing, through the process of mixing electrolyte solution and mineralizer were added at different concentrations for electrolyte solution, (1%, 0.7%, 0.5%, 0.2%, and 0.1%). The electrolyte solution was prepared by mixing sodium carbonate and sodium silicate by (2:1) ratio
... Show MorePhotodecomposition of dichlorobis N [4-Azo benzene aniline)2-hydroxy benzilidene] Copper (II) (Complexe A1) and dichloro N[2-Azo 3- sulphonic -2- naphthol) 6- carboxylic 2- hydroxy benzilidene] copper (II) (Complex A2).have been performed at λ = 373 nm for complex A1and at λ = 358 nm for complex A2 in dimethyl sulphoxide at 25C◦. the absorbance spectrum of these complexes have been recorded with time of irradiation in order to examine the kinetics of photodecay. The apparent rate constant (Kd) for the first order reaction has been calculated and found to be 1.1 ×10-2 min-1 for complexe A1 and 2.34 × 10-2 min-1 for camplexe A2. the primary quantum yields (Ø ) ha
... Show MoreThe spectral characteristics and the nonlinear optical properties of the mixed donor (C-480) acceptor (Rh-6G) have been determined. The spectral characteristics are studied by recording their absorption and fluorescence spectra. The nonlinear optical properties were measured by z-scan technique, using Q-switched Nd: YAG laser with 1064 nm wavelength. The results showed that the optimum concentration of acceptor is responsible for increasing the absorption and the emission bandwidth of donor to full range and to 242 nm respectively by the energy transfer process, also the efficiency of the process was increased by increasing the donor and acceptor concentration. The obtained nonlinear properties results of the mixture C-480/ Rh-6G showed
... Show MoreThroughout what mentioned above, It is obvious that the aware narrator in these biography models was the strongest tool in presenting the content, especially the biographies under study were written by feminine hands, striving to prove her identity by all means and ways. In addition, we can suppose that the hiding of she writer behind the character is no more than a mask, by which she want to mask herself so that she can express herself frankly and freely, especially when she talks about subjects that are inconsistent with the society, customs and traditions. It is important to refer that the existence of the participant narrator in the biographies under study does not prevent the presence of another narrator such as external or aware na
... Show MoreInformation systems and data exchange between government institutions are growing rapidly around the world, and with it, the threats to information within government departments are growing. In recent years, research into the development and construction of secure information systems in government institutions seems to be very effective. Based on information system principles, this study proposes a model for providing and evaluating security for all of the departments of government institutions. The requirements of any information system begin with the organization's surroundings and objectives. Most prior techniques did not take into account the organizational component on which the information system runs, despite the relevance of
... Show MoreAsphaltene is a component class that may precipitate from petroleum as a highly viscous and sticky material that is likely to cause deposition problems in a reservoir, in production well, transportation, and in process plants. It is more important to locate the asphaltene precipitation conditions (precipitation pressure and temperature) before the occurring problem of asphaltene deposition to prevent it and eliminate the burden of high treatment costs of this problem if it happens. There are different models which are used in this flow assurance problem (asphaltene precipitation and deposition problem) and these models depend on experimental testing of asphaltene properties. In this study, the used model was equation of
... Show MoreIn this study , extraction of irradiated high concentration hexavallent uranium from fission products ( high gamma radiation ) was carried out using multistages countercurrent continuous technique (mixer setller) , employing this technique requires a designing flow sheet that recover all the amounts of uranium and to minimize its losses in the nuclear waste streams. Due to the several parameters required to reach this design, SEPHIS program which is one of the famous code in this field were used to select the optimum conditions through many theoretical runs , finally the experimental results give a good assurance in SEPHIS results and its optimum conditions.
Graphic design constitutes the human necessity for the design action, so there is no design achievement that is not considered in its founding project and its final realization as a response to a specific necessity. As a result of knowledge, which is the product of experience and is the result of applied science, design is based on observation, study and development, leading to the main goal, which is the utilitarian and aesthetic function that is put into the final consideration of design, and drug packaging design has an important role in all marketing fields, as companies compete with each other to attract the largest number Possible from consumers in a way that guarantees them material profit, and in order to achieve this, it always
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