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1.
Sensors (Basel) ; 24(9)2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38732787

RESUMEN

With the recent advances in autonomous vehicles, there is an increasing need for sensors that can help monitor tire-road conditions and the forces that are applied to the tire. The footprint area of a tire that makes direct contact with the road surface, known as the contact patch, is a key parameter for determining a vehicle's effectiveness in accelerating, braking, and steering at various velocities. Road unevenness from features such as potholes and cracks results in large fluctuations in the contact patch surface area. Such conditions can eventually require the driver to perform driving maneuvers unorthodox to normal traffic patterns, such as excessive pedal depressions or large steering inputs, which can escalate to hazards such as the loss of control or impact. The integration of sensors into the inner liner of a tire has proven to be a promising method for extracting real-time tire-to-road contact patch interface data. In this research, a tire model is developed using Abaqus/CAE and analyzed using Abaqus/Explicit to study the nonlinear behavior of a rolling tire. Strain variations are investigated at the contact patch in three major longitudinal slip driving scenarios, including acceleration, braking, and free-rolling. Multiple vertical loading conditions on the tire are applied and studied. An intelligent tire prototype called KU-iTire is developed and tested to validate the strain results obtained from the simulations. Similar operating and loading conditions are applied to the physical prototype and the simulation model such that valid comparisons can be made. The experimental investigation focuses on the effectiveness of providing usable and reliable tire-to-road contact patch strain variation data under several longitudinal slip operating conditions. In this research, a correlation between FEA and experimental testing was observed between strain shape for free-rolling, acceleration, and braking conditions. A relationship between peak longitudinal strain and vertical load in free-rolling driving conditions was also observed and a correlation was observed between FEA and physical testing.

2.
BMC Musculoskelet Disord ; 22(1): 755, 2021 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-34479514

RESUMEN

BACKGROUND: Migraine and cervicogenic headache (CGH) are common headache disorders, although the large overlap of symptoms between them makes differential diagnosis challenging. To strengthen differential diagnosis, physical testing has been used to examine for the presence of musculoskeletal impairments in both conditions. This review aimed to systematically evaluate differences in physical examination findings between people with migraine, CGH and asymptomatic individuals. METHODS: The databases MEDLINE, PubMed, CINAHL, Web of Science, Scopus, EMBASE were searched from inception until January 2020. Risk of bias was assessed with the Downs and Black Scale for non-randomized controlled trials, and with the Quality Assessment of Diagnostic Accuracy Studies tool for diagnostic accuracy studies. When possible, meta-analyses with random effect models was performed. RESULTS: From 19,682 articles, 62 studies were included in this review and 41 were included in the meta-analyses. The results revealed: a) decreased range of motion [°] (ROM) on the flexion-rotation test (FRT) (17.67, 95%CI:13.69,21.65) and reduced neck flexion strength [N] (23.81, 95%CI:8.78,38.85) in CGH compared to migraine; b) compared to controls, migraineurs exhibit reduced flexion ROM [°] (- 2.85, 95%CI:-5.12,-0.58), lateral flexion ROM [°] (- 2.17, 95% CI:-3.75,-0.59) and FRT [°] (- 8.96, 95%CI:-13.22,-4.69), reduced cervical lordosis angle [°] (- 0.89, 95%CI:-1.72,-0.07), reduced pressure pain thresholds over the cranio-cervical region [kg/cm2], reduced neck extension strength [N] (- 11.13, 95%CI:-16.66,-5.6) and increased activity [%] of the trapezius (6.18, 95%CI:2.65,9.71) and anterior scalene muscles (2.87, 95%CI:0.81,4.94) during performance of the cranio-cervical flexion test; c) compared to controls, CGH patients exhibit decreased neck flexion (- 33.70, 95%CI:-47.23,-20.16) and extension (- 55.78, 95%CI:-77.56,-34.00) strength [N]. CONCLUSION: The FRT and neck flexion strength could support the differential diagnosis of CGH from migraine. Several physical tests were found to differentiate both headache types from asymptomatic individuals. Nevertheless, additional high-quality studies are required to corroborate these findings. STUDY REGISTRATION: Following indications of Prisma-P guidelines, this protocol was registered in PROSPERO on 21/05/2019 with the number CRD42019135269 . All amendments performed during the review were registered in PROSPERO, indicating the date and what and why was changed.


Asunto(s)
Trastornos Migrañosos , Cefalea Postraumática , Humanos , Trastornos Migrañosos/diagnóstico , Músculos del Cuello , Examen Físico , Cefalea Postraumática/diagnóstico , Cefalea Postraumática/epidemiología , Rango del Movimiento Articular
3.
Biol Sport ; 38(3): 377-390, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34475621

RESUMEN

This study describes the contemporary practices of strength and conditioning coaches in professional soccer. Fifty-two strength and conditioning coaches from professional leagues across 18 countries completed an online survey, consisting of 45 questions, with eight sections: (a) background information, (b) muscular strength and power development, (c) speed development, (d) plyometrics, (e) flexibility development, (f) physical testing, (g) technology use, and (h) programing. A frequency analysis was used to assess and report responses to fixed response questions, and thematic-analysis used for open-ended questions to create clear, identifiable and distinct themes. All strength and conditioning coaches were educated to degree level or higher, 65% held strength and conditioning certifications and 54% held soccer coaching certifications. Concentric (100%) and eccentric (98%) modes of resistance were the most commonly prescribed, whereas the squat (including variations) (52%) was deemed the most important exercise for soccer players. Hang clean (33%) and multiple hops/lunges (89%) were the most programed Olympic weightlifting and plyometric exercises. Global Positioning Systems (94%) were the most utilized technology-based equipment. Time, scheduling and fixtures were the biggest issues faced, which made it difficult to periodize training programs and apply appropriate training loads. Furthermore, strength and conditioning coaches would like to further integrate technology to comprehensively monitor and test players, while also believing that technology will continue to be developed and integrated in the future. Strength and conditioning coaches from professional soccer can use the information from this study to review current practices and also provide ideas for diversifying or modifying future practices.

4.
J Sports Sci ; 35(9): 912-920, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27352917

RESUMEN

This study investigated the two different time-of-day effect on team-handball-related short-term maximal physical performances. At two different time-of-day, fifteen young female team handball players performed different physical tests: HandGrip (HG) test, Ball-Throwing Velocity (BTV) test, Modified Agility T-test (MAT) and Repeated Shuttle-Sprint and Jump Ability (RSSJA) test. Rating of perceived exertion (RPE) scale was determined following the termination of the last test. Measurements were performed at two separate testing sessions (i.e., in the morning (7:00-8:30 h) and in the early evening (17:00-18:30 h)) in a randomised and counter-balanced setting on non-consecutive days. The results showed that HG (P = 0.0013), BTV (P = 0.0027) and MAT (P < 0.001) performances were better in the evening compared with the morning. During RSSJA, both best and mean sprint times were shorter in the evening compared to the morning (P < 0.001). Moreover, during the latter test, mean jump performance was higher in the evening compared to the morning (P = 0.026). However, there was no morning-evening difference in the best jump performance during RSSJA. Likewise, jump performance decrement was not affected by the time-of-day of testing. On the other hand, RPE fluctuated, with morning nadirs and afternoon/early evening highest values. The findings suggest that in female team handball players, team-handball-related short-term maximal physical performances were better in the afternoon than in the morning.


Asunto(s)
Rendimiento Atlético/fisiología , Deportes/fisiología , Temperatura Corporal , Femenino , Fuerza de la Mano , Humanos , Fase Luteínica , Destreza Motora/fisiología , Percepción , Esfuerzo Físico/fisiología , Factores de Tiempo , Adulto Joven
5.
J Man Manip Ther ; : 1-11, 2024 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-38963328

RESUMEN

AIM: To determine differences in physical examination findings between people with acute whiplash-associated disorders (WAD) with and without headache. METHODS: In this cross-sectional study, participants with acute WAD were evaluated to assess differences in the presence of physical impairments. The following were assessed: pain intensity on manual palpation the over spinous process of C1-C3, zygapophyseal joints of C0-C4, and trapezius, sternocleidomastoid, suboccipitalis, masseter and temporalis muscles; cervical range of motion (ROM); flexion-rotation test (FRT); forward head posture; cranio-cervical flexion test (CCFT); neck flexor and extensor endurance; pressure-pain thresholds (PPT) over neural structures and upper limb neural tests (ULNT) in addition to median UNLT + CCF. Correlation analyses were performed to assess the association between examination findings and headache intensity. Logistic regression and discriminant analyses were also performed. RESULTS: Forty-seven participants (26 men and 21 women; mean age = 38.9 years old) were included in the study. 60% of the participants presented with headache. Several examination findings were significantly different between groups. A group of examination findings composed of neck endurance, manual palpation over cervical and muscular structures, PPT, CCFT, ROM and FRT could discriminate between groups with a sensitivity of 86.7% and specificity of 90%. CONCLUSIONS: Several neuromusculoskeletal features are different between people with acute WAD with or without headache. A combination of features could distinguish between groups with high levels of sensitivity and specificity.

6.
J Orthop Sports Phys Ther ; 54(3): 201-208, 2024 03.
Artículo en Inglés | MEDLINE | ID: mdl-38284387

RESUMEN

OBJECTIVES: To (1) provide position-specific normative data for isometric cervical muscle strength and endurance in professional, male rugby players and (2) assess the relationship between age, height, weight, and playing position with cervical muscle strength and endurance. DESIGN: Cross-sectional study. METHODS: Professional rugby players completed peak isometric cervical strength testing followed by a test of cervical muscle endurance. Descriptive statistics for continuous variables with strength normalized to body weight were performed. Multiple linear regression was used to estimate associations between strength measurements. RESULTS: In total, 136 players participated including front-row forwards (27%), other forwards (28%), and backs (45%). Front-row forwards had significantly greater peak isometric cervical muscle strength than other position groups, with backs having the lowest strength. Extension produced the highest force for all 3 position groups (429 N ± 104 N), whereas flexion produced the least (275 N ± 65 N). Age was associated with increased isometric cervical muscle strength. There was a statistically significant relationship between peak flexion strength and flexion endurance (P = .003). The average time for the endurance tests were 55.7 (±17.1) seconds and 52.9 (±20.1) seconds for extension and flexion, respectively. Other forwards had lower cervical extension muscle endurance than backs and front-row forwards. CONCLUSIONS: Normative values for peak and endurance isometric strength in professional rugby players illustrate significant differences between playing position. Consider age, body weight, and intraindividual variability when interpreting cervical strength and endurance results. J Orthop Sports Phys Ther 2024;54(3):1-8. Epub 29 January 2024. doi:10.2519/jospt.2024.11830.


Asunto(s)
Rendimiento Atlético , Fútbol Americano , Humanos , Masculino , Estudios Transversales , Rugby , Fuerza Muscular/fisiología , Peso Corporal , Rendimiento Atlético/fisiología
7.
Int J Sports Physiol Perform ; 18(12): 1374-1379, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-37689401

RESUMEN

PURPOSE: Monitoring is a fundamental part of the training process to guarantee that the programmed training loads are executed by athletes and result in the intended adaptations and enhanced performance. A number of monitoring tools have emerged during the last century in sport. These tools capture different facets (eg, psychophysiological, physical, biomechanical) of acute training bouts and chronic adaptations while presenting specific advantages and limitations. Therefore, there is a need to identify what tools are more efficient in each sport context for better monitoring of training process. METHODS AND RESULTS: We present and discuss the fine-tuning approach for training monitoring, which consists of identifying and combining the best monitoring tools with experts' knowledge in different sport settings, designed to improve (1) the control of actual training loads and (2) understanding of athletes' training adaptations. Instead of using single-tool approaches or merely subjective decision making, the identification of the best combination of monitoring tools to assist experts' decisions in each specific context (ie, triangulation) is necessary to better understand the link between acute and chronic adaptations and their impact on health and performance. Future studies should elaborate on the identification of the best combination of monitoring tools for each specific sport setting. CONCLUSION: The fine-tuning monitoring approach requires the simultaneous use of several valid and practical tools, instead of a single tool, to improve the effectiveness of monitoring practices when added to experts' knowledge.


Asunto(s)
Deportes , Humanos , Atletas , Predicción
8.
Musculoskelet Sci Pract ; 64: 102738, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36870148

RESUMEN

BACKGROUND: People with whiplash-associated disorders (WAD) commonly present with a variety of physical impairments. However, the reliability of physical tests has not been established for patients with acute WAD. OBJECTIVE: To assess test-retest reliability of different physical tests in acute WAD. DESIGN: Intra-rater test-retest reliability. METHODS: Patients with acute WAD were recruited. Physical tests were used to evaluate articular, muscular and neural systems in two blocks of measurements separated by 10 min. Bland-Altman plots were performed to assess intrarater agreement, which included calculation of the mean difference (d) between rates, the 95% CI for d, the standard deviation of the differences and the 95% limits of agreement. Reliability was calculated via the standard error of measurement, the minimal detectable change, percent of agreement, the intraclass-correlation coefficient, and kappa coefficient. RESULTS: 47 patients participated. Test-retest reliability was excellent or good for almost all measures, except for extension ROM, ULTT for the radial nerve, and active cervical extension and upper cervical rotation performed in 4-point kneeling, which presented moderate reliability. Systematic bias was found in cervical ROM in flexion, left and right lateral-flexion, left and right rotation; left ULTT for radial nerve; right trapezius, suboccipitalis and temporalis muscles, left temporalis; C3, both sides of C1-C2, left C3-C4. CONCLUSION: The majority of physical tests achieved good or excellent test-retest intra-rater reliability when tested in patients with acute WAD. Findings must be considered with caution for those tests which demonstrated systematic bias. Additional research is warranted to evaluate inter-rater reliability.


Asunto(s)
Examen Físico , Lesiones por Latigazo Cervical , Humanos , Reproducibilidad de los Resultados , Rango del Movimiento Articular/fisiología , Lesiones por Latigazo Cervical/diagnóstico , Lesiones por Latigazo Cervical/complicaciones , Cuello , Enfermedad Aguda
9.
Musculoskelet Sci Pract ; 66: 102779, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37271677

RESUMEN

BACKGROUND: Provocation of headache on physical examination of the neck may reflect a role of cervical structures in the presence of acute whiplash-associated headache (WAH). OBJECTIVE: To determine differences in headache provocation during physical tests in people with and without WAH after a whiplash injury. DESIGN: Case-control study. METHODS: Forty-seven people with acute whiplash-associated disorders participated, 28 with WAH. Passive accessory intervertebral movement over the tubercle of C1, the spinous processes of C2-C3 and facet joints of C0-C4, the flexion-rotation test (FRT), manual palpation of cranio-cervical muscles and the upper limb neurodynamic test + cranio-cervical flexion were assessed bilaterally twice by a blinded examiner; headache provocation was determined. Cohen's kappa and Chi-squared were determined to evaluate the intra-rater reliability of test results and differences between groups, respectively. A logistic regression model was also performed. RESULTS: Intra-rater reliability of headache provocation was good or excellent for most tests. Significant differences between groups were found with higher positive tests in WAH for the assessment of C2 (68%), the most painful side of C0-C1 (57%), C1-C2 (75%) and C2-C3 (53%), most (79%) and least (25%) restricted sides of the FRT, and manual palpation of the most painful side for the trapezius (53%), masseter (50%) and temporalis (46%) muscles. Provocation of headache during the assessment of C2 and C1-C2 on the most painful side demonstrated the highest association with WAH. CONCLUSION: Mechanical provocation of headache is more frequent in people with WAH than in those without headache soon after a whiplash injury.


Asunto(s)
Lesiones por Latigazo Cervical , Humanos , Lesiones por Latigazo Cervical/complicaciones , Lesiones por Latigazo Cervical/diagnóstico , Estudios de Casos y Controles , Reproducibilidad de los Resultados , Vértebras Cervicales , Cefalea/diagnóstico , Cefalea/etiología , Examen Físico/métodos , Dolor
10.
J Exerc Rehabil ; 16(5): 432-441, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33178645

RESUMEN

The purpose of this study was to evaluate differences in multiple athletic performances, and to examine associations between athletic performance and Functional Movement Screen (FMS) in young soccer players. Forty-one soccer players were tested on peak height velocity (PHV), 5-, 10-, and 30-m sprint times, 505 change of direction (505 COD), Y-reactive agility tests, countermovement jump (CMJ), and squat jump (SJ) height. Significant main effects (P<0.01) were recorded in all tests except FMS total score whereas the U16 group outperformed U12 and U14 in almost each test. However, when the results were adjusted to the PHV 7 of 11 tests were nonsignificant. Significant associations were recorded between trunk stability push-up (TSPU) and 5 m (P=0.04) and 505 COD (preferred) times (P=0.01), and SJ height (P=0.03) in the U12. In the U14, significant associations were recoded between TSPU and SJ (P<0.01) and CMJ height (P=0.03). In the U16, significant associations were recorded between deep overhead squat and 5-m sprint time (P=0.02) and CMJ height (P=0.04). Results of this study indicate that athletic performance in young soccer players is multidimensional in nature, and it is a consequence of several factors including maturation, different training strategies, and movement proficiency.

11.
BMJ Open ; 9(11): e031587, 2019 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-31712341

RESUMEN

INTRODUCTION: Differential diagnosis of migraine and cervicogenic headache (CGH) can be challenging given the large overlap of symptoms, commonly leading to misdiagnosis and ineffective treatment. In order to strengthen the differential diagnosis of headache, previous studies have evaluated the utility of physical tests to examine for musculoskeletal impairment, mainly in the cervical spine, which could be provoking or triggering headache. However, no systematic review has attempted to evaluate whether physical tests can differentiate CGH from migraine or both conditions from asymptomatic subjects. METHODS/ANALYSIS: A systematic review protocol has been designed and is reported in line with Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P). A sensitive topic-based search strategy is planned which will include databases, hand searching of key journals and consultation of relevant leading authors in this field. Terms and keywords will be selected after discussion and agreement. Two independent reviewers will perform the search and select studies according to inclusion and exclusion criteria, including any cohort or observational studies evaluating the topic of this review; a third reviewer will confirm accuracy. A narrative synthesis will be developed for all included studies and, if possible, a meta-analysis will be conducted. The overall quality of the evidence will be assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) checklist for diagnostic accuracy studies and the Downs and Black scale for those studies where the QUADAS-2 checklist cannot be applied. ETHICS AND DISSEMINATION: Ethical approval is not required since no patient information will be collected. The results will provide a deeper understanding about the possibility of using physical tests to differentiate cervicogenic headache from migraine and from asymptomatic subjects, which has direct relevance for clinicians managing people with headache. The results will be published in a peer-reviewed journal and presented at scientific conferences. PROSPERO REGISTRATION NUMBER: CRD42019135269.


Asunto(s)
Trastornos Migrañosos/diagnóstico , Examen Físico , Cefalea Postraumática/diagnóstico , Proyectos de Investigación , Revisiones Sistemáticas como Asunto , Diagnóstico Diferencial , Humanos
12.
Artículo en Inglés | MEDLINE | ID: mdl-31717596

RESUMEN

The flood propagation at a confluence of channels exhibits a unique routing pattern, while there are few studies on the routing of dam-break flow in confluent channels. In this study, we conducted physical experiments and a numerical simulation to investigate the influence of different confluence angles on the routing of a dam-break flood. Experiments were carried out in smooth, transparent, rectangular prismatic channels to study the dam-break flow under four different confluence angles. The flow velocity was measured using an image processing technique, and the surface flow field was effectively captured by synchronously recording the particle motion images. Based on the variation of the water level and flow discharge, as the confluence angle increased, the retardation and abatement effects on the flood increased. Specifically, the flood arrival time was delayed by approximately 0.91% to 21.18%, and the peak flood discharge was reduced by approximately 9.05% to 58.36%. Combined with the surface flow field at the confluence and in the downstream sections, as the confluence angle increased, the impact points at the confluence and in the downstream straight sections moved upward, and the impact range was reduced. Combined with the pressure variation pattern, the routing of dam-break flow in the confluent channels experienced a process of impact-reflection-return-attenuation.


Asunto(s)
Inundaciones , Movimientos del Agua , Fenómenos Físicos
13.
Sports (Basel) ; 6(1)2018 Feb 13.
Artículo en Inglés | MEDLINE | ID: mdl-29910318

RESUMEN

The aim of the study was to investigate seasonal variations in fitness and performance indices of professional male soccer players. Eighteen professional male soccer players (age range 22⁻32 years) completed three similar sets of tests at three stages of the season: before preseason; after preseason and the middle of the competitive in-season. A significant decrease in body mass and percent fat was found during the preseason. A significant improvement (p < 0.05) was found in the vertical jump (preseason: 37.0 ± 5.3, post-preseason: 39.0 ± 4.8, mid-season: 40.3 ± 5.5 cm), the 4 × 10-m agility test (preseason: 8.1 ± 0.2, post-preseason: 7.9 ± 0.2, mid-season: 8.1 ± 0.3 s), flexibility (preseason: 45.2 ± 8.8, post-preseason: 48.2 ± 7.0, mid-season: 49.9 ± 6.9 cm) and aerobic capacity (preseason: 52.7 ± 6.6, post-preseason: 56.4 ± 6.0, mid-season: 57.4 ± 5.4 mL/kg/min) during preseason, with no further change during mid-season. Repeated sprint test (RST) (6 × 30-m) performance indices showed significant deterioration (p < 0.05) in ideal sprint time (IS; preseason: 21.8 ± 1.0, post-preseason: 23.0 ± 0.8, mid-season: 23.2 ± 0.8 s) and total sprint time (TS; preseason: 22.5 ± 0.7, post-preseason: 23.5 ± 0.6, mid-season: 23.8 ± 0.6 s) during preseason, with no further changes during mid-season. However, performance decrement (PD) significantly decreased during the preseason with no change during mid-season. The findings suggest that while power training was probably responsible for the anaerobic fitness improvement, the high-volume training led to improvement in aerobic fitness during the preseason. However, the low-intensity aerobic-type training, coupled with the high total training load, may have led to fatigue and decreases in IS and TS during the preseason.

14.
J R Soc Interface ; 13(124)2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-28339367

RESUMEN

The Mesozoic marked a time of experimentation in the tooth morphology of early mammals. One particular experiment involved the movement of three points, or cusps, on the surface of a molar tooth from a line into a triangle. This transition is exemplified by two extinct insectivorous mammals, Morganucodon (cusps in a line) and Kuehneotherium (cusps in a triangle). Here we test whether this difference in cusp arrangement, alongside cusp heights and angles between cusps, is associated with differences in the ability of the teeth to fracture proxy-insect prey. We gathered measurements from molar teeth of both species and used them to create physical models. We then measured the force, time and energy at fracture and peak force, and the amount of damage inflicted by the models on hard and soft gels encased in a tough film that mimicked the material properties of insects. The Morganucodon model required less force and energy to fracture hard gels and reach peak force compared with KuehneotheriumKuehneotherium required a similar time, force and energy to fracture soft gels but reduced the time, force and energy to reach peak force. More importantly, Kuehneotherium also inflicted more damage to both the hard and the soft gels. These results suggest that changes in dental morphology in some early mammals was driven primarily by selection for maximizing damage, and secondarily for maximizing biomechanical efficiency for a given food material property.


Asunto(s)
Evolución Biológica , Mamíferos/anatomía & histología , Mamíferos/fisiología , Animales
15.
J Endod ; 42(10): 1529-35, 2016 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-27523906

RESUMEN

INTRODUCTION: Sealers based on tricalcium silicate cement aim at an interaction of the sealer with the root canal wall, alkalinity with potential antimicrobial activity, and the ability to set in a wet field. The aim of this study was to characterize and investigate the properties of a new tricalcium silicate-based sealer and verify its compliance to ISO 6876 (2012). METHODS: A new tricalcium silicate-based sealer (Bio MM; St Joseph University, Beirut, Lebanon), BioRoot RCS (Septodont, St Maure de Fosses, France), and AH Plus (Dentsply, DeTrey, Konstanz, Germany) were investigated. Characterization using scanning electron microscopy, energy-dispersive spectroscopy, and X-ray diffraction analysis was performed. Furthermore, sealer setting time, flow, film thickness, and radiopacity were performed following ISO specifications. pH and ion leaching in solution were assessed by pH analysis and inductively coupled plasma. RESULTS: Bio MM and BioRoot RCS were both composed of tricalcium silicate and tantalum oxide in Bio MM and zirconium oxide in BioRoot RCS. In addition, the Bio MM contained calcium carbonate and a phosphate phase. The inorganic components of AH Plus were calcium tungstate and zirconium oxide. AH Plus complied with the ISO norms for both flow and film thickness. BioRoot RCS and Bio MM exhibited a lower flow and a higher film thickness than that specified for sealer cements in ISO 6876. All test sealers exhibited adequate radiopacity. CONCLUSIONS: Bio MM interacted with physiologic solution, thus showing potential for bioactivity. Sealer properties were acceptable and comparable with other sealers available clinically.


Asunto(s)
Compuestos de Calcio/química , Materiales de Obturación del Conducto Radicular/química , Silicatos/química , Cemento de Óxido de Zinc-Eugenol/química , Fenómenos Químicos , Cementos Dentales , Concentración de Iones de Hidrógeno , Ensayo de Materiales
16.
Ann Vasc Dis ; 6(1): 67-73, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23641287

RESUMEN

We developed a novel large-diameter graft "Triplex(®)" that uses a non-biodegradable material as a coating material. This time, in order to demonstrate the physical properties of Triplex(®) grafts, we conducted physical tests in accordance with the international guidelines, using the collagen coated vascular grafts (Hemashield, Boston Scientific, Natick, Massachusetts, USA) as the controls. The grafts were tested with regard to strength (burst strength, circumferential tensile strength, longitudinal tensile strength), suture retention strength, integral water permeability, water leakage (needle puncture, after using clamp), and change in luminal diameter following pacing stress according to ISO7198 and FDA guidance. As indicated by the results, we experimentally demonstrated that uniquely designed vascular graft Triplex(®) led to less blood leakage from the vascular graft and less leakage from the needle puncture, although it has fundamental physical properties comparable to those of the vascular grafts using biodegradable material that has been utilized conventionally in clinical settings. Triplex (®)is expected to play its role as a clinically beneficial next-generation vascular graft.

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