Background: The aims of the study were to evaluate the unclean/clean root canal surface areas with a histopathological cross section view of the root canal and the isthmus and to evaluate the efficiency of instrumentation to the isthmus using different rotary instrumentation techniques. Materials and Methods:The mesial roots of thirty human mandibular molars were divided into six groups, each group was composed of five roots (10 root canals)which prepared and irrigated as: Group one A: Protaper system to size F2 and hypodermic syringe, Group one B: Protaper system to size F2 and endoactivator system, Group two A:Wave One small then primary file and hypodermic syringe, Group two B:Wave One small then primary file and endoactivator system, Group three A: step back technique to size 25 file as MAFand hypodermic syringe, Group three B: step back technique to size 25 file as MAFand endoactivator system . All the roots were sectioned at 2mm, 6mm ,12mm from the apex and studied by histopathological cross section. The degree of cleaning of each section was measured by the use of Autocade 2004 software system. Result :the least uncleaned isthmus surface area at coronal, middle and apical section was found by the Protaper system with endoactivator which represented the mean of the percentage of uncleaned surface area of 16.87%, 14.32% and 9.55% respectively. The system that produced least uncleaned canal wall was by Protaper system with endoactivator at coronal ,middle ,and apical sections of 12.21%, 9.14% and 18.55% respectively . The mean of highest percentage of increased canal diameter which was Protaper system, Wave One system and then step back. The comparison between the groups in the means which showed that the highest percentage of decrease in isthmus area was with the Protaper system, Wave One system and lastly the step back. Conclusions:The Protaper system with endoactivator was the best system in canal and isthmus cleaning.
Any person, regardless of his location in the air, whether he was kidnapped or trained, and then he performs a certain work, believes that his work is in vain, and by God, his deeds. I wonder if those who hold him in the first place will be safe in good form. He said that the essence of justice in the story is the story:
These are given the meaning we have fought in the fact that each group of. He went beyond creating a group of blocs, sects, and parties. If justice indicated one meaning, these relationships between people and peace would diminish. In fact, justice has only one concept, but there are several associations with it in the field of divorced one of these synonyms. However, the variation in racist drums in the encounte
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The history of the arts is closely connected with the history of humankind, since it is impossible to separate our scientific and artistic advances’. Therefore, the current research focuses on the close bond between art and other disciplines. The connection of the arts to the sciences is unequivocal and undisputed; the contributions of artists to the various scientific domains are clear. If one scrutinises the ability of artists to participate in building societies, one will find that the arts have penetrated deeply into a range of products and inventions, starting with the pencil and ending with the missile. The artist’s contributions play a part in the minutest of details across all fields of industry: production, craftsmanship, me
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The influx of Arab Qahtani and Nizari tribes continued to the countries of Baluchistan and the Levant in pre-Islamic times until the Levant became open to the Arab-Islamic tide during the first century AH. The Islamic Orient until the early Islamic Arab Army reached the western borders of China. What we will see in the folds of the search.
Different additives are used in drilling fluids when the demanded properties cannot be gotten with clays. Drilling muds needs several additives and materials to give good characteristics. There are local alternatives more suitable for enhancing the rheology and filtration of drilling fluids. An experimental work had been conducted to assess the suitability of using potato starch to enhance rheological properties and filtration in drilling mud. This study investigated the potato starch as a viscosifier and fluid losses agent in drilling fluid. Results from this study proved that rheological properties of potato starch mud increased when pH of drilling fluid is increased. Potato starch could be used to enhance gel strength at low pH
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Different additives are used in drilling fluids when the demanded properties cannot be gotten with clays. Drilling muds needs several additives and materials to give good characteristics. There are local alternatives more suitable for enhancing the rheology and filtration of drilling fluids. An experimental work had been conducted to assess the suitability of using potato starch to enhance rheological properties and filtration in drilling mud. This study investigated the potato starch as a viscosifier and fluid losses agent in drilling fluid. Results from this study proved that rheological properties of potato starch mud increased when pH of drilling fluid is increased. Potato starch could be used to enhance gel strength at low pH
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In the name of of Allah the Merciful
Praise be to God, and blessings and peace be upon the Messenger of God, Muhammad, and upon his family and his family and peace, and after:
The honor of every knowledge of honor is related to it, and since the science of interpretation is related to the Book of God Almighty; it is considered one of the most noble and longest of sciences, and this science began long ago as the early ages of Islam have expanded the Islamic state, and people entered the religion of God in cohorts, and the mixture mixed In tongues, and people did not know much about the meanings of the Qur’an, so the need for authorship in this great knowledge was severe, and pe
The thermoelectric power as a function of temperature for the Iron-Manganese-Aluminum, Fe-Mn-Al, alloys for manganese concentrations 0.04, 0.06, 0.08, 0.10 and 0.20 have been investigated in the temperature range 300 K. to 500 K. these results showed that the thermoelectric power coefficient in hot probe measurements showed that the electrons are the majority charge carriers in these alloys.
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The creative production of the philosophy of beauty in artistic works constitutes a step towards development and progress by meeting the growing and changing needs of humanity according to various factors, including those related to the human situation and others related to technical outputs, as well as the multiplicity of the field for the emergence of new artistic currents and movements concerned with graphic production and communication and communication processes that It is associated with imagination and freedom from social and cultural constraints, in which the design production seeks to link more realistic intellectual contents with the achievements of the creative artwork as a communication system to involve the recipient (the vi
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