Search results for "Beam"
showing 10 items of 2126 documents
Practical Calculation Models for Column Footing and Comparison with Experimental Data
2017
In this paper, a simplified calculation model for the prediction of the load-carrying capacity of an RC column footing with a square cross section is presented. A detailed background of available experimental data and existing models for the prediction of the load-carrying capacity of slender and deep footings is presented. Cases of flexural failure and punching shear failures for slender footing and concrete strut crushing and tie yielding in deep members are analyzed. The aim of the paper is to propose a simple design formula for slender and deep footing verified by available experimental data and in agreement with other existing expressions. Expressions of the maximum mechanical ratio of…
Inferior alveolar nerve trajectory, mental foramen location and incidence of mental nerve anterior loop
2017
Background: Injury of the inferior alveolar nerve (IAN) is a serious intraoperative complication that may occur during routine surgical procedures, such as dental implant placement or extraction of impacted teeth. Thus, the purpose of this study was to analyze the trajectory of the mandibular canal (MC), the location of the mental foramen (MF) and the presence and extension of an anterior loop of the mental nerve (AL). Study Design: In this cross-sectional study, a total of 348 CBCTs were analyzed. Distances from MC to the surface of the basal, medial and lateral cortical of the mandible were measured at the level of the second molar, first molar and second premolar. Location of the MF rela…
Evaluation of the position of the posterior superior alveolar artery in relation to the maxillary sinus using the Cone-Beam computed tomography scans
2017
Background The aim of the present study was to evaluate the diameter, relationship and position of the posterior superior alveolar artery and its relationship with the alveolar ridge, the medial wall of the maxillary sinus, the prevalence of pathologic conditions and the maxillary sinus septa on CBCT images. Material and Methods A total of 200 CBCT images (400 maxillary sinuses) of patients over 20 years of age were evaluated. The distances between the lower border of the artery and the alveolar crest and between the artery and the medial wall of the sinus and the diameter of the artery were measured. The position of the artery, the presence of pathologic conditions and septa were recorded …
Tooth abnormalities in individuals with unilateral alveolar clefts : a comparison between sides using cone-beam computed tomography
2017
Background: Tooth abnormalities are most often present in individuals with oral clefts than general population, and lead to a long-term impact on facial anatomy and self-esteem. The purpose of this study was to compare the proportion of dental anomalies between the cleft side and non-cleft side in individuals with non-syndromic unilateral alveolar clefts (AC). Material and Methods: Twenty cone beam computed tomography (CBCT) scans were converted into threedimensional (3D) virtual models. The dental anomalies considered were: tooth agenesis; supernumerary teeth; giroversion; and microdontia. Statistical analysis was performed using the McNemar?s test and Fisher?s exact test ( p < 0.05). Resu…
Surgically-oriented anatomical study of mandibular premolars: A CBCT study
2019
Background The knowledge of root canal anatomy and of the anatomical relationship should be considered mandatory when planning surgical endodontics. The aim of the study was to investigate the anatomical features of mandibular premolars, evaluating their relationship with mental nerve. Material and methods CBCT scans were evaluated recording the number of roots, root canal configuration and the relationship with mental nerve of 100 mandibular premolars. After simulating a resection of 3 mm of the root, the shape and the number of canals, and the distance to the buccal and lingual bone plate and to the mental foramen was evaluated. Results The one root - one canal configuration was the most …
Correlation between the visibility of submandibular fossa and mandibular canal cortication on panoramic radiographs and submandibular fossa depth on …
2017
Background To identify a correlation between the submandibular fossa (SF) visibility and mandibular canal (MC) cortication on panoramic image and the depth of SF measured on CBCT and also correlation between the depth of SF and vertical and horizontal location of MC on CBCT. Material and Methods 500 CBCT scans and panoramic radiographs were evaluated. SF depth types were classified as type I ( 3mm) on CBCT. Visibility of SF and the cortication of MC on panoramic radiographs were compared with the depth of SF on CBCT. Distances between MC and mandibular inferior, buccal and lingual cortices were measured. Results No statistically significant correlation was found between radiolucent appearan…
Danger zone analysis using cone beam computed tomography after apical enlargement with K3 and K3XF in a manikin model
2015
Background The objective of the study was to evaluate and compare how apical enlargement with K3 and K3XF nickel-titanium (NiTi) rotary instruments reduces the root thickness in the danger zone and affects canal transportation and centering ability in mandibular molar mesial canals in a manikin extracted tooth model. Material and Methods Seventy-two mesial root canals of first mandibular molars were instrumented. Initial and post-instrumentation Cone Beam Computed Tomography scans were performed after root canal preparation up to size 25, 30, 35 and 40 files. Canal transportation, canal centering and remaining root dentin thickness toward the danger zone were calculated in sections 1, 2 and…
Dental pulp calcifications in prehistoric and historical skeletal remains
2020
Abstract Background The prevalence of hard tissue formations in the dental pulp varies considerably. Beside ageing processes and irritations of the dental pulp, etiological associations with cardiovascular disease and dietary habits have been discussed, which are of particular research interest. The aim of this pilot study is to provide new insights on structural and etiological factors involved in the development of pulp calcifications by investigating skeletal remains from different (pre)historic periods. Methods The jaws of 46 skeletons excavated in central Germany, were examined for the presence of pulp stones using digital volume tomography (DVT). A total of 1122 teeth were examined wi…
Extricating New Physics Scenarios at DUNE with High Energy Beams
2017
The proposed Deep Underground Neutrino Experiment (DUNE) utilizes a wide-band on-axis tunable muon-(anti)neutrino beam with a baseline of 1300 km to search for CP violation with high precision. Given the long baseline, DUNE is also sensitive to effects due to non-standard neutrino interactions (NSI) which can interfere with the standard 3-flavor oscillation paradigm. In this Letter, we exploit the tunability of the DUNE neutrino beam over a wide-range of energies and utilize a new theoretical metric to devise an experimental strategy for separating oscillation effects due to NSI from the standard 3-flavor oscillation scenario. Using our metric, we obtain an optimal combination of beam tunes…
Nanoscale strain-engineering and optics of quantum emitters in a two-dimensional semiconductor
2017
We present deterministic fabrication of a two-dimensional lattice of quantum emitters in an atomically thin semiconductor. Resonant laser spectroscopy of these emitters reveals localized exciton states that exhibit stable, bright and high-purity single photon emission.