Search results for "USP"
showing 10 items of 1290 documents
Suspended core tellurite glass optical fibers for infrared supercontinuum generation
2011
International audience; We report the fabrication and characterization of tellurite TeO(2)-ZnO-Na(2)O (TZN) microstructured suspended core optical fibers (MOFs). These fibers are designed for infrared supercontinuum generation with zero dispersion wavelength (ZDW) at 1.451 mu m. The measured losses at this wavelength are approximately 6 dB/m for a MOF with a 2.2 mu m diameter core. The effective area of a particular fiber is 3.5 mu m(2) and the nonlinear coefficient is calculated to be 437 W(-1)km(-1). By pumping a 20 cm long fiber at 1.56 mu m with a sub-nj femtosecond laser source, we generate a supercontinuum (SC) spanning over 800 nm in the 1-2 mu m wavelength range.
Dense Solid-Liquid Off-Bottom Suspension Dynamics: Simulation and Experiment
2009
Dense solid-liquid off-bottom suspension inside a baffled mechanically agitated stirred tank equipped with a standard Rushton turbine is investigated. Dynamic evolution of the suspension from start up to steady state conditions has been inspected by both visual experiments and computational fluid dynamics. A classical Eulerian-Eulerian Multi Fluid Model along with the “homogeneous” k-epsilon turbulence model is adopted to simulate suspension dynamics. In these systems the drag inter-phase force affects both solids suspension and distribution. Therefore, different computational approaches are tested in order to compute this term. Simulation results are compared with images acquired on the re…
Study of the microstructure and efficiency of YSZ-SPS finely structured ceramic coatings
2018
Thanks to the using of liquid carrier, suspension plasma spray (SPS) enables the manufacture of finely structured coatings. As for conventional plasma spraying (APS), the microstructures of SPS coatings can be tailored by controlling the spray conditions. However, SPS is more complicated than APS due to its number of modifiable parameters.This thesis aims to provide a more fundamental understanding of the relationship between SPS process parameters and the properties of YSZ coatings by identifying generic models based on the use of mathematical statistical methods for the study of influence and sensitivity of the individual parameters.Systematic experiments were carried out to study the inf…
Periodontal health in shortened dental arches: A 10-year RCT
2020
Journal of prosthodontic research 64(4), 498-505 (2020). doi:10.1016/j.jpor.2020.01.005
Retrospective evaluation of the clinical performance of direct composite restorations using the snow-plow technique : up to 4 years follow-up
2019
Background To evaluate the clinical performance of direct composite restorations using the snowplow technique with up to 4 years of follow-up. Material and methods In this retrospective study, 101 class II composite restorations which were placed in permanent molars (n = 19) and premolars (n = 82) in 85 patients by the snowplow technique, were evaluated according to the modified USPHS criteria. A Kaplan-Meier analysis with a 95% confidence level was used to calculate the survival probability. Results Of the 101 teeth examined, tooth failure was identified in 8 teeth due to secondary caries (3%), marginal gap (2%), marginal discoloration (1%) and restoration breakdown (2%) which required rep…
A comparison between dental measurements taken from CBCT models and those taken from a digital method.
2011
The aims of the study were to assess speed, reliability, accuracy, and reproducibility in measuring mesiodistal tooth sizes, bicanine widths, bimolar widths, and arch lengths (ALs) using cone beam computed tomography (CBCT) and to compare them with the same measurements obtained using a two-dimensional (2D) Digital Method. Plaster study models were made for 27 patients and then digitalized and measured using a 2D Digital Method. CBCTs were undertaken on the same 27 patients using the Dental Picasso Master 3D® and the images obtained were then analysed using the InVivoDental program. The correlation study of the two measuring methods, which were compared by determining the regression paramet…
Prevalence of impacted premolars in a Turkish population and considerations for surgical treatment
2010
Objective: The aim of this study was to identify the prevalence, associated pathology and symptoms, and treatment of impacted premolars in a Turkish population. Study Design: This retrospective study examined panoramic radiographs and clinical records of 9,000 patients who presented consecutively at our oral and maxillofacial surgery clinics between January 1998 and January 2009. In addition to demographic data (patient sex and age), data was compiled on the number and location of impacted missing maxillary and mandibular premolars, retained deciduous molars, associated pathologies and symptoms, and treatment methods. Results: A total of 105 impacted maxillary or mandibular premolars were o…
Molar distalization with pendulum appliances in the mixed dentition: effects on the position of unerupted canines and premolars.
2004
Introduction: The pendulum appliance allows for rapid molar distalization without the need for patient compliance. Its efficiency has been confirmed in a number of clinical studies. However, the potential interactions and positional changes between the deciduous molars used for dental anchorage and the erupted and unerupted permanent teeth have yet to be clarified when this appliance is used for molar distalization in the mixed dentition. Methods: Twenty-nine patients in the mixed dentition each received a modified pendulum appliance with a distal screw and a preactivated pendulum spring for bilateral distalization of the maxillary molars. The patients were divided into 4 groups based on de…
Prevalence of Talon cusp in Indian population
2011
Aim: To investigate the prevalence of the talon cusps in a sample of Indian dental patients and their distribution among different types of teeth. To determine the presence of other dental anomalies associated with the talon cusps. Methodology: 2740 out patients (1523 males and 1217 females) attending Oral Medicine department from November 2010 to January 2011 were screened for the presence of talon cusps and were subjected to Intra Oral Peri-apical (IOPA) radiograph to rule out any associated anomalies or peri-apical changes. Results: Talon cusps were detected in 16 out of 2740 patients (person prevalence 0.58%). Thirty one teeth were found to have talon cusp. Maxillary lateral incisors we…
Influence of first and second premolar extraction or non-extraction treatments on mandibular third molar angulation and position. A comparative study.
2009
The mandibular third molar (3M) is the tooth that is most often impacted, with lack of space being one of the reasons. In some orthodontic treatments, premolars are extracted in order to create space. The aims of our study are: firstly, to assess the changes in the angulation and position of the 3M in cases treated either with or without extraction of the first or second premolars; secondly, to analyse the variation in the gonial angle and the degree of inclusion of the 3M; and lastly, to establish a predictive impaction model for 3M. This study included 88 patients: 28 patients treated with extractions of first premolars, 30 with second premolars and 30 without. The initial and final ortho…