The purpose of this work was to study the effects of the Nd:YAG laser on exposed dentinal
tubules of human extracted teeth using a scanning electron microscope (SEM). Eighty 2.5mm-thick
slices were cut at the cementoenamel junction from 20 extracted human teeth with an electric saw. A
diamond bur was used to remove the cementum layer to expose the dentinal tubules. Each slice was
sectioned into four equal quadrants and the specimens were randomly divided into four groups (A to D ).
Groups B to D were lased for 2 mins using an Nd:YAG laser at 6 pulses per second at energy outputs of
80 , 100 and 120 mJ. Group A served as control. Under SEM observation, nonlased specimens showed
numerous exposed dentinal tubules. SEM observation revealed that application of Nd:YAG laser at
energy output of 80 mJ may cause melting of dentin and partial closure of exposed dentinal tubules
without dentin surface cracking. But when the energy output raised to 100 and 120 mJ more sealing of
dentinal tubules occurs. Heat generation occurred in all lased groups but the amount of temperature
increase was within the permissible limits(less than 5.5⁰C). The measured sealing depths were from 3-
5μm for groups B-D and the width of the created groove was 30μm in all lased groups. In conclusion
lasing with nanosecond Nd:YAG with a wavelength of 1064nm at 120mJ with 6Hz for 2 minutes (group
D) shows the efficient laser parameters for complete sealing of exposed dentinal tubules without
temperature increase to the damaging level of the pulp tissue.
The objective of the research is to determine the nature of the strategic direction of the institution and its impact on enhancing the indicators of institutional performance. The strategic direction is the main purpose for which it was found. Therefore, it is the main engine for all activities and tasks that the institution can carry out to achieve its objectives within the environment in which it operates. The promotion of corporate performance indicators is one of the major challenges that senior management must address in order to help the organization invest its human resources in the best possible way.
The research problem was determined by means of the intentional sample, consisting of (33) members
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Flurbiprofen (FLB) is chemically 2-(3- fluoro-4-phenyl phenyl) propanoic acid. It is a nonsteroidal anti-inflammatory drug (NSAID) used in the treatment of rheumatoid arthritis and osteoarthritis. Oral administration of this drug is associated with severe gastrointestinal side effects like ulceration and gastrointestinal bleeding. The solution to this problem lies in the fact that topically applied NSAIDs are safer than orally. This study aims to prepare different topical semisolid formulation of FLB as cream base (o/w), (w/o) and gel base using different gel-forming agents in different concentrations. Comparing characterization properties in addition to release and diffusion study for all the prepared formulas to select the best on
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Background: Green Tea is made from the leaf of the plant “Camellia sinensisâ€. Green tea is reported to contain thousands of bioactive ingredients including catechins which have shown great promise for having antimicrobial effects. Periodontal diseases represent one of the most prevalent diseases around the world and the main etiologic factor behind it, is plaque accumulation, in addition certain kinds of bacteria have been detected frequently in subjects suffering from periodontitis, Several studies suggested that the outcome of periodontal treatment is better if particular pathogens including Aggregatibacteractinomycetemcomitans can no longer be detected after therapy. Materials and Methods: plaque samples were collected from 2
... Show MoreIn the present work, a kinetic study was performed to the extraction of phosphate from Iraqi Akashat phosphate ore using organic acid. Leaching was studied using lactic acid for the separation of calcareous materials (mainly calcite). Reaction conditions were 2% by weight acid concentration and 5ml/gm of acid volume to ore weight ratio. Reaction time was taken in the range 2 to 30 minutes (step 2 minutes) to determine the reaction rate constant k based on the change in calcite concentration. To determine value of activation energy when reaction temperature is varied from 25 to 65 , another investigation was accomplished. Through the kinetic data, it was found that selective leaching was controlled by
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This study investigates the influence of asymmetric involute teeth profiles for helical gears on the bending stress. Theoretically, bending stress has been estimated in spur involute gears which have symmetric teeth profile by based on the Lewis, 1892 equation. Later, this equation is developed by, Abdullah, 2012. to determine the effect of an asymmetric tooth profile for the spur gear on the bending stress. And then these equations are applied with stress concentration factor once for symmetric and once other for asymmetric teeth profile. In this paper, the bending stresses for various types of helical gear with various types of asymmetric teeth profile are calculated numerically for defined the stress concentration fac
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Background: Corticotomy-assisted orthodontic treatment is done to induce a state of increased tissue turnover and transient osteopenia, which is followed by a faster rate of orthodontic tooth movement. It considered as an adjunct treatment option for orthodontic treatment of adults. The aim of this Study was to elucidate the effectiveness of a new surgical approach for acceleration of maxillary canine retraction in human with laser assisted flapless corticotomy and evaluate its effect on vitality of pulp and gingival sulcus depth. Materials and methods: the sample comprised of 15 Iraqi patients (9 females and 6 males; mean age 21.7), who were required extraction for their maxillary first premolars followed by retraction of the canines as pa
... Show MoreThe health care industry is witnessing an increasing trend in the use of generic medicines because of their presumed low cost compared with innovator medicines. The aim of this study was to determine and compare the performance of the copy drug Osveral®and its innovator drug deferasirox (Exjade®).
A prospective observational study including 223 patients receiving the branded medicine Exjade®and 101 patients receiving the copy Osveral®was carried out. Data were assessed for a 1-year period and included clinical symptoms, serum ferrit
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This research aims to estimate stock returns, according to the Rough Set Theory approach, test its effectiveness and accuracy in predicting stock returns and their potential in the field of financial markets, and rationalize investor decisions. The research sample is totaling (10) companies traded at Iraq Stock Exchange. The results showed a remarkable Rough Set Theory application in data reduction, contributing to the rationalization of investment decisions. The most prominent conclusions are the capability of rough set theory in dealing with financial data and applying it for forecasting stock returns.The research provides those interested in investing stocks in financial
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