Search results for "Root"
showing 10 items of 1237 documents
Classification of Gingival Recession
2018
Gingival recession is a common finding in many patients and is clinically manifested by an apical displacement of the gingival margin in relation to the cemento-enamel junction (CEJ). Various classification systems have been proposed to classify gingival recession defects and to predict final root coverage outcomes. Among them, the Miller classification is still the most commonly used among dental practitioners and researchers. This chapter reviews the different classification systems available for gingival recession defects and explores the strengths and limitations of them.
Canal shaping with a reciprocating system is easy to learn.
2018
To assess progressive learning of root canal shaping in order to define the number of simulated canals in resin blocks needed to reach a level of learning beyond which no further improvement in performance is observed.A total of 216 simulated canals in resin blocks were instrumented by 18 operators without experience in Endodontics and by 18 Endodontists. The R25 file of the Reciproc system (VDW, Munich, Germany) was used to prepare the canals. The blocks were photographed before and after instrumentation. An analysis was made of the variations in the dimensions of the canals at 6 locations and of the instrumentation time. A Student's t-test was used to analyse the data (P 0.05).The group …
Influence of the Geometrical Cross-Section Design on the Dynamic Cyclic Fatigue Resistance of NiTi Endodontic Rotary Files—An In Vitro Study
2021
The aim of this study was to analyze and compare the influence of the geometrical cross-section design on the dynamic cyclic fatigue resistance of NiTi endodontic rotary files. Materials and Methods: Forty sterile endodontic rotary files were selected and distributed into the following study groups: A: 25.06 double S-shaped cross-section NiTi alloy endodontic rotary files (Mtwo) (n = 10)
Definition of Gingival Recession and Anatomical Considerations
2018
The gingiva is an integral part of the periodontium that covers the cervical portions of the teeth and the alveolar processes of the jaws. In health, the closely adapted gingival tissues provide effective protection against mechanical trauma and bacterial invasion and also play a critical role in aesthetics. Therefore, a recession of the gingival margin not only affects the aesthetic appearance but may cause several adverse consequences due to exposure of the root surface. This chapter provides a definition of gingival recession and gives a basic overview of the anatomical characteristics of the gingiva. A basic understanding of the macroscopic and microscopic features of healthy gingiva is…
Root resorption caused by osteoma growth
2015
introduction. Osteoma is a benign and asymptomatic neoplasm, consisting of well-differentiated mature bone. The solitary osteoma may be classified as: peripheral when arising from the periosteum, central when arising from the endosteum and extraskeletal when arising in soft tissue. The etiology of osteoma is still unclear. Some reported cas- es did have a clear history of trauma; however, this was not the case in the majority of cases. Whereas peripheral osteomas are fairly easy to diagnose, central osteomas pose a more challenging diagnostic problem and need to be differentiated from other similar lesions of the jaws, such as central ossifying fibroma, osteoblastoma, cementoblas- toma and …
Periodontal therapy for patients before and after radiotherapy : a review of the literature and topics of interest for clinicians
2018
Background To review and discuss important topics regarding periodontal treatment pre- and post-radiotherapy for head and neck cancer in human patients; to discuss the references for adequate techniques, the appropriate moment for tooth extractions and periodontal management; and to discuss the prevention of osteoradionecrosis. Material and Methods Thirty-nine studies including original studies, randomized clinical trials (RCTs) and reviews were searched in online databases MEDLINE (PubMed) and the Cochrane library. No year of publication restriction was applied. Results Language was restricted to English, and the following Medical Subject Heading terms were used: radiotherapy, radiation th…
Observation of s-Channel Production of Single Top Quarks at the Tevatron
2014
We report the first observation of single-top-quark production in the s channel through the combination of the CDF and D0 measurements of the cross section in proton-antiproton collisions at a center-of-mass energy of 1.96 TeV. The data correspond to total integrated luminosities of up to 9.7fb-1 per experiment. The measured cross section is σs=1.29-0.24+0.26pb. The probability of observing a statistical fluctuation of the background to a cross section of the observed size or larger is 1.8×10-10, corresponding to a significance of 6.3 standard deviations for the presence of an s-channel contribution to the production of single-top quarks. © 2014 American Physical Society.
Jet quenching as a probe of the initial stages in heavy-ion collisions
2019
Jet quenching provides a very flexible variety of observables which are sensitive to different energy- and time-scales of the strongly interacting matter created in heavy-ion collisions. Exploiting this versatility would make jet quenching an excellent chronometer of the yoctosecond structure of the evolution process. Here we show, for the first time, that a combination of jet quenching observables is sensitive to the initial stages of heavy-ion collisions, when the approach to local thermal equilibrium is expected to happen. Specifically, we find that in order to reproduce at the same time the inclusive particle production suppression, $R_{AA}$, and the high-$p_T$ azimuthal asymmetries, $v…
Retama species growing in different ecological-climatic areas of northeastern Algeria have a narrow range of rhizobia that form a novel phylogenetic …
2009
International audience; Sixty-seven isolates were isolated from nodules collected on roots of Mediterranean shrubby legumes Retama raetam and Retama sphaerocarpa growing in seven ecological-climatic areas of northeastern Algeria. Genetic diversity of the Retama isolates was analyzed based on genotyping by restriction fragment length polymorphism of PCR-amplified fragments of the 16S rRNA gene, the intergenic spacer (IGS) region between the 16S and 23S rRNA genes (IGS), and the symbiotic genes nifH and nodC. Eleven haplotypes assigned to the Bradyrhizobium genus were identified. Significant biogeographical differentiation of the rhizobial populations was found, but one haplotype was predomin…
Fiber Post Removal: Comparative Study Using a New Post Concept
2009
Objectives: To evaluate the time required to remove endodontic posts made of quartz and glass fibers, and compare them to a new glass fiber post designed for easy removal on the basis of efficiency and tooth damages. Methods: 40 human single-rooted teeth were treated endodontically and randomly assigned to four fiber posts groups: 1) was restored with Premier#90 (Innotech); 2) with DT#2 Lightpost (Dentsply); 3) with Unicore#3 (Ultradent); 4) with a special, soft-cored “S” glass fiber post ER-Prosthetic#3 (Overfibers). An impression of the canal was taken prior post cementation. The posts were luted with Panavia F and adhesive (Kuraray). All the specimens were mounted in a dental simulation …