214 research outputs found
Evaluation of biomechanical effects of interocclusal surfaces on the mandible
ABSTRACT
Introduction: Only few studies in the literature employ a mathematical model in the evaluation of the stress which follows the
application of loads and constraints onto the mandible. Therefore, new approaches are needed so that the study of this phenomenon
can rely less on the clinical hypothesis and experience of the operator, while taking advantage of the many benefits that virtual
representations and mathematical calculations present. Aim of the study is to determine, by means of the finite element method
(FEM), the stress produced onto the mandible as a result of the application of a force on itself, in association or not to the perioral
musculature and according to the dental support given by the positioning of an interocclusal surface at three different levels: mesial,
intermediate and distal.
Aim: The aim is to allow a more objective evaluation of this phenomenon, its absolute repeatability, as well as to acquire important
clinical informations concerning the role of orthodontic and gnathologic appliances.
Materials and methods: Starting from a 1:1 scale model of the mandible (human adult male), a virtual three - dimensional (3D)
representation was first obtained thanks to a dedicate software; it was then imported into a second software in order to permit the
discretization into finite elements of the virtual model and the attribution of its mechanical properties. Finally, thanks to a specific
software, it was possible to simulate the presence of load and constraints and to evaluate the stress status by using pseudo - colors.
Results: The stress generated following the application of a force onto the mandible, undergoes significant variations in relation to the
dental support and the presence or absence of the perioral musculature.
Conclusions: Following the results of our research, we consider FEM as a valid and interesting method for this purpose, however
additional FEM conducted studies are necessary in order to assess this phenomenon in more detail and determine the role of the
perioral musculature as well as the possible clinical implications
What inspires young people to study physics? Results from the WG1 interviews survey
The talk will focus on the main results of an Interview based Survey of 1st Year University Physics Students, carried out within Working Group 1 (WG1) of the HOPE project. Among the HOPE activities, 112 interviews have been conducted in 16 universities, in order to investigate in some depth the factors that inspire young people to study physics and to identify possible critical factors which can produce the dropping out.The individual interviews have been carried out on a selection of students who had previously answered the WG1 Questionnaire on the inspirational factors, led by Gareth Jones from the Imperial College, London. In the talk, we will show how the interviews helped us to unpack the main results achieved with the questionnaire survey. In particular, we will present a comprehensive picture of \u201ccuriosity\u201d which turned out to be the predominant motivating factor and we will show how the interviews can throw extra light on reasons for comparatively low scores for factors like (i) enhancing employment prospects, (ii) effect of physics teacher, (iii) scientists in the family
Pilot Study of a New Mandibular Advancement Device
This study was conducted to determine the efficacy of a customized mandibular advancement device (MAD) in the treatment of obstructive sleep apnea (OSA). Eight patients (M = 3; F = 5; mean age = 56.3 ± 9.4) with a diagnosis of OSA confirmed by polysomnography (PSG) were re-cruited on the basis of the following inclusion criteria: apnea-hypopnea index (AHI) > 5, age between 18 and 75 years, body mass index (BMI) < 25, and PSG data available at baseline (T0). All were treated with the new NOAŸ MAD by OrthoApnea (NOAŸ ) for at least 3 months; PSG with NOA in situ was performed after 3 months of treatment (T1). The following parameters were calculated at T0 and T1: AHI, supine AHI, oxygen desaturation index (ODI), percentage of recording time spent with oxygen saturation <90% (SpO2 < 90%), and mean oxygen desaturation (MeanSpO2%). Data were submitted for statistical analysis. The baseline values were AHI = 21.33 ± 14.79, supine AHI = 35.64 ± 12.80, ODI = 17.51 ± 13.5, SpO2 < 90% = 7.82 ± 17.08, and MeanSpO2% = 93.45 ± 1.86. Four patients had mild OSA (5 > AHI < 15), one moderate OSA (15 > AHI < 30), and three severe OSA (AHI > 30). After treatment with NOAŸ, statistically significant improvements in AHI (8.6 ± 4.21) and supine AHI (11.21 ± 7.26) were recorded. OrthoApnea NOAŸ could be an effective alternative in the treatment of OSA: the device improved the PSG parameters assessed
Predictability of InvisalignÂź Clear Aligners Using OrthoPulseÂź: A Retrospective Study
This preliminary retrospective study evaluates how effective the OrthoPulse (Biolux Technology, Austria) is in increasing the predictability of orthodontic treatment in patients treated with Invisalign (R) clear aligners (Align Technology Inc., Tempe, AZ, USA). A group of 376 patients were treated with Invisalign (R) orthodontic clear aligners in association with an OrthoPulse (R) . The OrthoPulse (R) was prescribed for 10 min a day for the entire duration of the orthodontic treatment. The OrthoPulse (R) App remotely tracked the percentage compliance of each patient. The number of aligners planned with the ClinCheck software at the beginning of the treatment and the number of total aligners (including the adjunctive aligners) used to finish the treatment were then considered. After applying inclusion/exclusion criteria, a total of 40 patients remained in the study and were compared with a control group of 40 patients with the same characteristics as the study group. A statistical analysis was carried out to investigate whether using OrthoPulse (R) led to a statistical reduction in the number of adjunctive aligners, thus leading to a more accurate prediction of the treatment. The statistical analysis showed that patients who used OrthoPulse (R) needed fewer finishing aligners and a greater predictability of the treatment was obtained. In fact, in the treated group the average number of additional aligners represented 66.5% of the initial aligners, whereas in the control group 103.4% of the initially planned aligners were needed. In conclusion, in patients treated with clear aligners, OrthoPulse (R) would appear to increase the predictability of orthodontic treatment with clear aligners, thus reducing the number of finishing phase requirements
Student interviews on inspirational and drop-out factors progress report (Sub-Group WG1-B)
Progress report on the survey on inspirational and drop-out factors we carried out, within the activities of WG1, through individual interviews to physics students. In particular, we present: 1) the research groups involved in the survey and in the data analysis; 2) the sample; 3) the research questions; 4) the quantitative and qualitative research methods of data analysis we are designing; 4) the preliminary analysis and the problematic issues we are dealing with; 5) discussion, implications and future plans
Physiotherapists and Osteopathsâ Attitudes: Training in Management of Temporomandibular Disorders
Temporomandibular disorders (TMDs) are a condition which has multifactorial etiology. The most acknowledged method to classify TMDs is the diagnostic criteria (DC) introduced firstly by Dworkin. This protocol considers different aspects that are not only biological, but even psychosocial. Diagnosis is often based on anamnesis, physical examination and instrumental diagnosis. TMDs are classified as intra-articular and/or extra-articular disorders. Common signs and symptoms include jaw pain and dysfunction, earache, headache, facial pain, limitation to opening the mouth, ear pain and temporomandibular joint (TMJ) noises. This study regards two kind of clinicians that started in the last years to be more involved in the treatment of TMDs: osteopaths (OOs) and physiotherapists (PTs). The purpose is to analyze their attitude and clinical approach on patients affected by TMDs. Four hundred therapists answered an anonymous questionnaire regarding TMJ and TMDs. OOs showed greater knowledges on TMDs and TMJ and, the therapists with both qualifications seemed to be most confident in treating patients with TMDs. In conclusion this study highlights OOs and all the clinicians with this qualification, have a higher confidence in treating patients with TMD than the others. Dentists and orthodontists, according to this study, should co-work with OOs and PTs, because they are the specialists more requested by them than other kinds of specialists
Understanding first-year studentsâ curiosity and interest about physics : Lessons learned from the HOPE project
This paper focuses on results of an interview based survey of first-year university physics students, carried out within the EU Horizons in Physics Education (HOPE) project (http://hopenetwork.eu/). 94 interviews conducted in 13 universities have been analyzed to investigate the factors that inspire young people to study physics. In particular, the main motivational factor, which was proven to consist of personal interest and curiosity, was unfolded into different categories and detailed interest profiles were produced. The results are arguably useful to help academic curriculum developers and teaching personnel in physics departments to provide guidance to students in developing and focusing their interest towards specific sub-fields and/or to design targeted recruitment and outreach initiatives.Peer reviewe
Stress and displacement pattern evaluation using two different palatal expanders in unilateral cleft lip and palate: a three-dimensional finite element analysis
Combination of searches for heavy spin-1 resonances using 139 fbâ1 of proton-proton collision data at s = 13 TeV with the ATLAS detector
A combination of searches for new heavy spin-1 resonances decaying into different pairings of W, Z, or Higgs bosons, as well as directly into leptons or quarks, is presented. The data sample used corresponds to 139 fbâ1 of proton-proton collisions at
= 13 TeV collected during 2015â2018 with the ATLAS detector at the CERN Large Hadron Collider. Analyses selecting quark pairs (qq, bb,
, and tb) or third-generation leptons (ÏÎœ and ÏÏ) are included in this kind of combination for the first time. A simplified model predicting a spin-1 heavy vector-boson triplet is used. Cross-section limits are set at the 95% confidence level and are compared with predictions for the benchmark model. These limits are also expressed in terms of constraints on couplings of the heavy vector-boson triplet to quarks, leptons, and the Higgs boson. The complementarity of the various analyses increases the sensitivity to new physics, and the resulting constraints are stronger than those from any individual analysis considered. The data exclude a heavy vector-boson triplet with mass below 5.8 TeV in a weakly coupled scenario, below 4.4 TeV in a strongly coupled scenario, and up to 1.5 TeV in the case of production via vector-boson fusion
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