Background: An accurate adaptation of the crown to the finish line is essential to minimize cement dissolution and to preserve periodontium in fixed partial denture cases. An accurate adaptation of crown is possible only when preparation details are captured adequately in the impression and transferred to cast. For these reasons, gingival displacement is necessary to capture subgingival preparation details.The aim of the present study is to measure in vivo the horizontal displacement of the gingival sulcus obtained by using three new cordless retraction materials (Magic Foam Cord®, Racegel and Astringent Retraction Paste) in comparison to medicated retraction cord. Materials and method: Thirty-two patients requiring porcelain fused to metal fixed partial denture for replacement of a missing maxillary posterior tooth (either one of thepremolars or the first molar). The patients are randomly divided into four groups of eight patients each according to the type of gingival retraction material used as follows: Group I: Medicated retraction cord (racemic epinephrine hydrochloride 0.3 ± 0.2 mg per inch of cord, #00), Group II: Magic Foam Cord® (expanding polyvinyl siloxane), Group III: Racegel (25% aluminum chloride gel) and Group IV: Astringent Retraction Paste (15% aluminum chloride paste). Three depth orientation grooves were prepared in the buccal and palatal surfaces of a maxillary premolar parallel with the long axis of the tooth, extending from the middle third to the gingival third with the level of the free gingiva using a flat-ended diamond fissure bur. Impression of the gingival sulcus was then made using monophase polyether impression material (Impregum™ Penta™ Soft, 3M ESPE, Germany), before and after gingival retraction with either of the aforementioned gingival retraction materials. The sulcus width, before and after gingival retraction was measured on the master cast (in µm), after its sectioning longitudinally bucco-palatally at the middle of the prepared grooves using a rotary diamond disc. The measurement carried out by using digital microscope (Dino-Lite)at a magnification of 230X. The horizontal gingival displacement (the distance from the end of each prepared groove to the crest of the gingiva) measured by subtracting the gingival sulcus width after retraction from that before retraction. Results: The findings of the present study showed that the highest mean of horizontal gingival displacement is recorded by Group IV (Astringent Retraction Paste) (250.7900 µm), whereas the lowest mean of horizontal gingival displacement is recorded by Group III (Racegel) (78.0988 µm). One-way ANOVA test showed statistically highly significant differences among groups (p< 0.01). Least Significant Difference test (LSD test) was also used to make multiple comparisons among groups and revealed a statistically highly significant difference between each two groups (p< 0.01). Conclusion: The two new gingival retraction pastes (Astringent Retraction Paste and Magic Foam Cord®) could be used for gingival retraction as alternatives to medicated retraction cord. They offer advantages of simplified placement technique and shorter application time with greater gingival retraction. Meanwhile, the use of Racegel alone is not recommended for gingival retraction since it provides the least gingival displacement.
Education quality evaluation is one of the objectives of education quality. The evaluation includes assessing the education standards and academic program outcomes to develop intellectual, scientific and practical concepts for the educational structure. It considers the determination of the rates of the number of accepted students and graduates. The research focuses on "what are the levels of education quality according to the evaluation mechanisms in the design department" to enhance the quality system and the objectives of theoretical and applied education.
It is identifying the levels of education quality and evaluating it according to the numbers and rates of graduate students of the design department branches for morning and ev
The article describes a certain computation method of -arcs to construct the number of distinct -arcs in for . In this method, a new approach employed to compute the number of -arcs and the number of distinct arcs respectively. This approach is based on choosing the number of inequivalent classes } of -secant distributions that is the number of 4-secant, 3-secant, 2-secant, 1-secant and 0-secant in each process. The maximum size of -arc that has been constructed by this method is . The new method is a new tool to deal with the programming difficulties that sometimes may lead to programming problems represented by the increasing number of arcs. It is essential to reduce the established number of -arcs in each cons
... Show Moreتناولنا في هذه الدراسة التأكيد على تطوير المناهج الدراسية بأتجاه تنمية قيم التسامح والتعايش السلمي ، لان ثقافة التسامح باتت من الضرورات الملحة التي يفرضها الواقع الراهن لمواجهة العنف المجتمعي ، مما يوجب الحرص على ترسيخ القيم الانسانية ، لان التسامح من الصفات التي تحبها النفوس وتنجذب اليها القلوب .
والقيم الاخلاقية والسلوكية كالتسامح وغيرها ، من الامور الرئيسية لعمليتي التربية والتعليم في المدارس وال
... Show MoreThe research tackles an important subject, namely, the light text and how it works well in the Arab television programs. The methodological framework of the research presents the research problem stated in the following question: How can the text be used and what is its impact in the Arab TV programs? The importance of this research is that it deals with the subject of light text and its impact on Arab television programs.
This study is useful to the workers and scholars in the field of lighting as well as the goal of the research in (studying of the employment of light text in Arab television programs).
The limits of research were manifested in the study of the light text and how to make use of it
... Show MoreIn this study, active knife and fixed knife of single-row disc silage machine has three different clearance C1, C2 and C3 (1, 3 and 5 mm) and it is tried in three different working speed V1, V2 and V3 (1.8, 2.5 and 3.7 km / h) and PTO speed (540 min-1) and machine's fuel consumption (l/h), average power consumption (kW), field energy consumption (kW/da), product energy consumption (kW/t), field working capacity (da/h), product working capacity (t/h) and Chopping size distribution characteristics of the fragmented material were determined. It has been found that knife-counter knife clearances smaller than 3 mm (1 mm) and larger (5 mm) have a negative effect on machine performance in general. In terms of fuel and power consumptions, the m
... Show MoreThis study presents the effect of laser energy on burning loss of magnesium from the holes' drilled in aluminum alloy 5052. High energy free running pulsed Nd:Glass laser of 300 µs pulse duration has been used to perform the experiments. The laser energy was varied from 1.0 to 8.0 Joules, The drilling processes have been carried out under atmospheric pressure and vacuum inside a specially designed chamber. Microhardness of the blind drilled holes has been investigated .The results indicated that the magnesium loss could be manipulated by adjusting the focusing conditions of the laser beam. Almost, the obtained holes were free of cracks with low taper and low sputter deposition. .The holes performed under atmospheric conditions have high
... Show MoreBackground: Mother-infant bonding is an important psychological step postpartum and disturbed relationship may carry dramatic consequences as a psychological disorder which may affect the periodontal health of the mother. The aim of the present study was to assess the effect of the postpartum Mother-infant bonding on their periodontal condition. Materials and Methods: Mothers in the postpartum period with age range 20-35 years were subjected to postpartum Bonding Questionnaire (PBQ). Periodontal health status was assessed by measuring probing pocket depth and clinical attachment level. Results: The mean values of both probing pocket depth (PPD) and clinical attachment loss (CAL) were higher among disordered mothers than mothers with normal
... Show MoreAbstract
Although the subject of biofuels industry is linked directly to the energy sector, but has links and numerous indirect effects, in particular effects on the environment and agriculture, this study (opportunities and challenges of biofuels industry and impact on the development of the agricultural sector in developing countries) a modest step to identify the industry in detail and identify the types of products and raw materials entering, then define or limit the positive and negative impacts of this industry in General and for specific products In particular, detailed, and then flip all those effects on the agricultural sector in developing countries can benef
... Show MoreThe impacts of harvested cropland in the double cropping region (DCR) of the northern China plains (NCP) on the regional climate are examined using surface meteorological data and the satellite-derived normalized difference vegetation index (NDVI) and land surface temperature (LST). The NDVI data are used to distinguish the DCR from the single cropping region (SCR) in the NCP. Notable increases in LST in the period May–June are found in the area identified as the DCR on the basis of the NDVI data. The difference between the mean daily maximum temperature averaged over the DCR and SCR stations peaks at 1.27°C in June. The specific humidity in the DCR is significantly smaller than in