Background: The access cavity is a critical stage in root canal therapy and it may influence the subsequent steps of the treatment. The new minimally invasive endodontic access cavity preparation concept aims to preserve sound tooth structure by conserving as much intact dentine as possible including the pulp chamber's roof, to keep the teeth from fracturing during and after endodontic treatment. While there is great interest in such access opening designs in numerous publications, still there is a lack of scientific evidence to support the application of such modern access cavity designs in clinical practice. This review aims to critically examine the literature on minimal access cavity preparations, explain the effect of minimally invasive access cavity designs on various aspects of root canal treatment, and identify areas where additional research is required. Data: An electronic search for English-language articles was performed using the following databases: Google Scholar, PubMed, and Research Gate. The following keywords were used: "minimally invasive access cavity", "conservative endodontic cavity ", and "classification of access cavity". Study selection: 64 papers that were the most relevant to the topics in this review were selected between 1969 to 26 February 2022. Conclusions: Minimally invasive access cavities can be classified into conservative, ultraconservative, truss access, caries and restorative-driven cavities. There is a deficiency of proof that a minimally invasive access cavity maintains the resistance to fracture of endodontically treated teeth greater than traditional access cavities. There was no difference in the percentage of untouched walls and debris removal in teeth with conservative vs traditional access cavities, however, truss and ultraconservative access cavities resulted in poor irrigation efficacy compared to traditional ones. Also, the lower cyclic fatigue resistance of rotary instruments and root canal obturation with voids were associated with minimally invasive access cavities. The studies about minimally invasive access cavities still have a wide range of methodological disadvantages or register unsatisfactory or inconclusive results. Therefore, further research on this topic is needed especially with the everyday advancement of techniques and armamentarium used in endodontics.
In this paper, mesoscale modeling is performed to simulate and understand fracture behavior of two concrete composites: cement and asphalt concrete using disk-shaped compact tension (DCT) tests. Mesoscale models are used as alternative to macroscale models to obtain better realistic behavior of composite and heterogeneous materials such as cement and asphalt concrete. In mesoscale models, aggregate and matrix are represented as distinct materials and each material has its characteristic properties. Disk-shaped compact tension test is used to obtain tensile strength and fracture energy of materials. This test can be used as a better alternative to other tests such as three points bending tests because it is more convenient for both field and
... Show MoreThe modern nation state, by virtue of its institutional nature, is divided into political and non-political institutions according to their respective jurisdictions. It is natural for non-political institutions to perform their functions under the control of the political establishment, for two reasons: first, Second: Ensuring the achievement of cooperation, harmony and integration between these different institutions in serving the stability of the society and its continuity and achieving its supreme objectives. The location of the military establishment is part of the non-political institutions of the state, since it carries out a non-political function that is based on defending the homeland against any threats that may threaten its s
... Show More<p>In the mobile phone system, it is highly desirable to estimate the loss of the track not only to improve performance but also to achieve an accurate estimate of financial feasibility; the inaccurate estimate of track loss either leads to performance degradation or increased cost. Various models have been introduced to accurately estimate the path loss. One of these models is the Okomura / Hata model, which is recommended for estimating path loss in cellular systems that use micro cells. This system is suitable for use in a variety of environments. This study examines the comparison of path loss models for statistical analysis derived from experimental data collected in urban and suburban areas at frequencies of 150-1500 MHz
... Show MoreNeurolinguistics is a new science, which studies the close relationship between language and neuroscience, and this new interdisciplinary field confirms the functional integration between language and the nervous system, that is, the movement of linguistic information in the brain in receiving, acquiring and producing to achieve linguistic communication; Because language is in fact a mental process that takes place only through the nervous system, and this research shows the benefit of each of these two fields to the other, and this science includes important topics, including: language acquisition, the linguistic abilities of the two hemispheres of the brain, the linguistic responsibility of the brain centers, and the time limit for langua
... Show MoreAt the beginning of the twentieth century distorting handling totalitarian phenomena of art, which can be called the stage of the test, transition from the theory of ideal theory and other realistic is not cushy, since it requires vision and reading and other concepts, and in light of this dialectic manifested research problem by asking the following Is affected by the design idealism and realism. Through the above mentioned questions, the researcher found rationale for addressing this problem, the study through his research, which is marked (idealism and realism in a comparative study design). And demonstrated the importance of research in the identification of the concept and the effectiveness of the two theories idealism and realism a
... Show MoreAjloun reserve is the most important reserved areas set up by the Jordanian government to encourage development and ecotourism, is located on the green mountains of Ajloun north of Jordan, was founded in 1989 and follow The Royal Society for the conservation of the natur, an area of 13 km2, and covered with thick forests of oak trees and Butm, maple and others, characterized by the diversity of vital consists of 319 species of medicinal and aromatic plants and wild flowers, and where there are 40 species of birds, 14 species of mammals, 16 reptiles, 5 species of plants registered in the world. The Reserve has a great importance in Jordan ,it is the most reservations attractive to tourists, both internally and externally, and prov
... Show MoreSound effects are considered to be a key element in children’s theatre, for it relays the context and amplifies its understandability, acceptability and its impact on the audience, so it’s a fundamental method in portraying the characters within the idea or the story, to produce the title and content with completeness in its relations that are associated with the rest of the fundamental elements represented in lighting, costumes, dialogue, decoration, etc. And this research included a set of subjects that are related to implementing the sound effects used in the Iraqi children’s theatre plays, chapter one included the problem and the need for studying this subject, as well as its importance and aim, and specifying the basic phrases
... Show MoreObjectives: To assess the information of mothers regarding asthmatic child care, and to find out the relationship between information of mothers and some of demographic characteristic such as age of mothers, Level of education, and away of child feeding. Methodology: Quantitative design (a descriptive study) was conducted in pediatric hospital in Kirkuk city from the period of first of July 2011 to the end of March 2012. To achieve the objectives of the study, non probability sample of (50) mothers having asthmatic children who attend to the pediatric hospital. The data are collected through utilization
Designing cloth is a part from culture and civilization of the area of every state to prove its being in all times because it is grown with Man to establish both goals: usefulness and beauty.It is necessary that designer puts in his mind the importance of the designing sources that he derives his designs from , because those sources are also important in that time especially :The Iraqi Ancient Civilization , the Islamic Civilization and Iraqi Folklores . Not to use the cloth sources that doesn't have well known roots in addition to lacking of elements and bases of balance in its different aspects. In conclusion to that studying research subject comes. (Balance Role in designing cloth curtains) The idea or the problem of the research is t
... Show MoreBackground: Potentially malignant oral disorders (PMODs) are common precursors of oral squamous cell carcinoma (OSCC). Neoangiogenesis and signalling are important intermediate biomarkers that may govern the progression of dysplastic mucosa into carcinoma. Aims: Evaluate the importance of CD34 and Wnt3 expression in PMODs and OSCCs in relation to their clinicopathological parameters. Settings and Design: Prospective cross-sectional study. Materials and Methods: Immunohistochemical staining for CD34 and Wnt3 was performed for 41 samples. These included 27 PMODs, six OSCCs and eight normal gingival and alveolar mucosa. Analysis of variance (ANOVA) and post-hoc tests were applied. P<0.05 was considered statistically significant. Results: CD34
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