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.
Emily Bronte is born in Yorkshire on 30 July 1818. Her father, Rev. Patrick Bronte, is a man of intelligence and determination which enables him to gain an admission as a sizar to 81. John's Cambridge in 1802. He has six children where Emily is the fifth. The mother is a young beautiful girl who belong to an important family. Both Emily's parents try to teach
Their children well, support them all the time and elevate them to
"-.../
high levels. This causes an eagerness towards reading and writing, but the happiness of the children is affected by the sickness and later on by the death of their mother in 1821. After that things would
... Show MoreArchitecture forms theoretical summaries and multi systems that have the essence of change, and that what distinguishes Architecture from other sciences and their systems. Architecture means way of life via its expressional products and that appears through its systems. These systems are based on formative and technological properties in form, structure, services and materials as well as
their moral forms. All these are associated with techniques and facilities in order to establish integrated system.
Architectural creation does not come from void but it depends on a conception base to create a new condition for creative architectural product. The general problem of the research concentrated on limited theoretical and practica
Purpose – The research aims to introduce sustainable agricultural development and the possibility of its application in the Iraqi agricultural sector by setting a proposed plan by which to overcome obstacles and then advance the reality of the agricultural sector in Iraq and the fact that the process of achieving agricultural development in the Iraqi agricultural sector today has become more sophisticated and more distant than before. The study adopted the descriptive analytical approach based on the principles of economic theory to clarify the shortcomings in the process of harmony between the three main elements of sustainable agricultural development, which are natural, social, and manufactured.
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The Islamic Issue did not rise the “widespread arguments” in contemporary times, just as the issue of applying Islamic Law. Just as the Islamic forces used this purpose, or employed it during their march to reach to power by adopting the sacred as motivation towered the power, or control the governance. However, the reality show that this goal remained within the boundaries of slogans in the sense of a teleological slogan, and did not go beyond the limits of advocacy or arrangement as the primary source of legislation with differences of teleological reasoning, in a manner that reflected an intellectual problem about the validity of the use of this concept or the ability to apply and enforce the law in today's world, to impose
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Among the issues that preoccupied ancient and modern grammarians is the phenomenon of grammatical disagreement among grammarians and their differences in many grammatical issues that many of them go back to the phenomenon of dialectical difference, so this filled our thinking with a lot of things that led us to look at the side of the reasons for this grammatical difference, and here lies the significance of research to know that it is a linguistic phenomenon dealing with the living language used among the Arabs and linguistic phenomena that reflect linguistic reality as well. Thus our chagrin determination in research and investigation in this issue is the scarcity of dialectical studies at the compositional grammar side, and the lack o
... Show MoreBackground: Insulin resistance is present in 50% or more of patients with primary hypothyroidism. Metformin can decrease TSH levels in these patients by a complex matter, this can be of great help in clinical practice.
Objective: This study was designed to evaluate the effect of metformin in reducing TSH levels in patients with primary hypothyroidism.
Methods: Hundred patients with primary hypothyroidism, 82 females, 18 males were included in this study, everyone was followed up for two months after adding metformin 850 mg twice daily in addition to thyroxin.
Results: 36 patients (36%) have a normal baseline TSH and no change after 2 months, 64 pa
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Abstract
We produced a study in Estimation for Reliability of the Exponential distribution based on the Bayesian approach. These estimates are derived using Bayesian approaches. In the Bayesian approach, the parameter of the Exponential distribution is assumed to be random variable .we derived bayes estimators of reliability under four types when the prior distribution for the scale parameter of the Exponential distribution is: Inverse Chi-squar
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Before the unit environmental problems serious the issues of the environment and conservation of contemporary issues important in the developed and developing worlds, it was natural that leads increasing global awareness to alert a group of intellectuals, scientists and politicians to the seriousness of this problem and the call to take steps deeper and more comprehensive with respect to the environment humanitarian based on the study of the various elements of this environment and a greater understanding of the relationships among them, and on this basis, steps have been taken to target the environment and to identify problems and make efforts to achieve the goals I: stop the deterioration of the environment and the second impro
... Show MoreThe cartographic representation of geographical phenomenon considers the essential base in geographical analysis since as it supports the vertical house which is apartment houses consist of apartments which represent civil phenomenon , the aim of this study is to project the rule of cartographic representation methods in geographical analysis and make comparison in economic and social aspects for two approaches , the vertical and construction building methods.
The expand of city horizontally represent a problem in itself because it leads to loss of civil lands and overpass the agricultural lands as a result ,the ratio of habitation of land usage is so large in comparison with another usages of lands of the cities ; therefore ; many co
We have studied theoretically the response of atomic three- level cascade scheme
of rubidium vapor to a strong laser under conditions in which electromagnetically
induced transparency would be induced on a weak probe beam. We show that the
medium that is an opaque to a probe laser can, by applying both lasers
simultaneously, be made transparent.