43 results on '"Aix Marseille Univ, CNRS, ISM, Inst Movement Sci, Marseille, France"'
Search Results
2. Local tissue effects and peri‐implant bone healing induced by implant surface treatment: an in vivo study in the sheep
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Olivier Richart, Patrick Chabrand, Inès Msolli, Nicolas Rousseau, Arnaud Destainville, Jean-Louis Milan, Aix Marseille Univ, CNRS, ISM, Inst Movement Sci, Marseille, France, Selenium Medical, 9049 rue de Québec, CS80875, 17043 La Rochelle, France, Abys Medical, 40 rue Chef de Baie, 17000 La Rochelle, France, Institut du Mouvement et de l’appareil Locomoteur [Hôpital Sainte-Marguerite - APHM] (IML), Assistance Publique - Hôpitaux de Marseille (APHM)-Hôpital Sainte-Marguerite [CHU - APHM] (Hôpitaux Sud )-Rhumatologie [Sainte- Marguerite - APHM] ( Hôpitaux Sud), Assistance Publique - Hôpitaux de Marseille (APHM)-Hôpital Sainte-Marguerite [CHU - APHM] (Hôpitaux Sud ), Institut des Sciences du Mouvement Etienne Jules Marey (ISM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), and Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS)
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0301 basic medicine ,Implant surface ,Surface Properties ,FOS: Physical sciences ,Dentistry ,Bone healing ,Peri implant bone ,Osseointegration ,03 medical and health sciences ,0302 clinical medicine ,sheep model ,In vivo ,dental implants ,Bone cell ,Animals ,Medicine ,Femur ,[PHYS.MECA.BIOM]Physics [physics]/Mechanics [physics]/Biomechanics [physics.med-ph] ,[SDV.IB.BIO]Life Sciences [q-bio]/Bioengineering/Biomaterials ,Titanium ,Sheep ,business.industry ,osseointegration ,X-Ray Microtomography ,030206 dentistry ,surface treatment ,Physics - Medical Physics ,030104 developmental biology ,Dental Prosthesis Design ,Coronal plane ,Periodontics ,Medical Physics (physics.med-ph) ,Implant ,business - Abstract
Objective: The aim of this study was to assess, through biological analysis, the local effects and osseointegration of dental implants incorporating surface micro/nanofeatures compared to implants of identical design without surface treatment. Background: Known to impact bone cell behavior, surface chemical and topography modifications target improved osseointegration and long-term success of dental implants. Very few studies assess the performance of implants presenting both micro-and nanofeatures in vivo on the animal models used in preclinical studies for medical device certification. Methods: Implant surfaces were characterized in terms of topography and surface chemical composition. After 4 weeks and 13 weeks of implantation in sheep femoral condyles, forty implants were evaluated through micro-computed tomography, histopathologic, and histomorphometric analyses. Results: No local adverse effects were observed around implants. Histomorphometric analyses showed significantly higher bone-to-implant contact in the coronal region of the surface treated implant at week 4 and week 13, respectively 79.3$\pm$11.2% and 86.4$\pm$6.7%, compared to the untreated implant's 68.3$\pm$8.8% and 74.8$\pm$13%. Micro-computed tomography analyses revealed that healing patterns differed between coronal and apical regions, with higher coronal boneto-implant contact at week 13. Histopathologic results showed, at week 13, bone healing around the surface treated implant with undistinguishable defect margins while the untreated implant still presented bone condensation and traces of the initial drill defect. Conclusion: Our results suggest that the surface treated implant not only shows no deleterious effects on local tissues but also promotes faster bone healing around the implant. (word count: 241, Journal of Periodontal Research, Wiley, 2021
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- 2021
3. Mechanical performance comparison of two surgical constructs for wrist four-corner arthrodesis via dorsal and radial approaches
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Julien Ballerini, Mark Ross, Jean-Louis Milan, Laurent Vigouroux, Benjamin Goislard de Monsabert, Philippe Bellemere, Barthélémy Faudot, Institut des Sciences du Mouvement Etienne Jules Marey (ISM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), APHM, Institute for Locomotion, Department of Orthopaedics and Traumatology, St Marguerite Hospital, Marseille, France, NewClip Technics, Haute-Goulaine, France, Brisbane Hand & UpperLimb, Brisbane, Australia, Institut de la Main Nantes Atlantique, Nantes, France, Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Chirurgie orthopédique et traumatologie [Hôpital Sainte-Marguerite - APHM], Hôpital Sainte-Marguerite [CHU - APHM] (Hôpitaux Sud )-Assistance Publique - Hôpitaux de Marseille (APHM)-Aix Marseille Université (AMU), Aix Marseille Univ, CNRS, ISM, Inst Movement Sci, Marseille, France, Brisbane Hand & UpperLimb, and Aix Marseille Université (AMU)-Assistance Publique - Hôpitaux de Marseille (APHM)-Hôpital Sainte-Marguerite [CHU - APHM] (Hôpitaux Sud )
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Wrist Joint ,Computer science ,Arthrodesis ,medicine.medical_treatment ,Wrist surgery ,Surgical approach ,Bone Screws ,Biophysics ,FOS: Physical sciences ,[SDV.MHEP.CHI]Life Sciences [q-bio]/Human health and pathology/Surgery ,Wrist ,Modelling ,03 medical and health sciences ,0302 clinical medicine ,Finite element ,medicine ,von Mises yield criterion ,Humans ,Orthopedics and Sports Medicine ,Biomechanics ,[PHYS.MECA.BIOM]Physics [physics]/Mechanics [physics]/Biomechanics [physics.med-ph] ,[SDV.IB.BIO]Life Sciences [q-bio]/Bioengineering/Biomaterials ,Finite element Modelling ,Stress concentration ,Aged ,Mechanical Phenomena ,Orthodontics ,Scaphoid Bone ,[SPI.MECA.BIOM]Engineering Sciences [physics]/Mechanics [physics.med-ph]/Biomechanics [physics.med-ph] ,030229 sport sciences ,Physics - Medical Physics ,Finite element method ,Biomechanical Phenomena ,Carpal bones ,medicine.anatomical_structure ,Treatment Outcome ,Scaphoid bone ,[SDV.IB]Life Sciences [q-bio]/Bioengineering ,Four-corner arthrodesis ,Medical Physics (physics.med-ph) ,Bone Plates ,030217 neurology & neurosurgery - Abstract
International audience; Background: Four-corner arthrodesis, which involves fusing four carpal bones while removing the scaphoid bone, is a standard surgery for the treatment of advanced stages of wrist arthritis. Nowadays, it can be performed using a dorsal approach by fixing a plate to the bones and a new radial approach is in development. To date, there is no consensus on the biomechanically optimal and most reliable surgical construct for four-corner arthrodesis. Methods: To evaluate them biomechanically and thus assist the surgeon in choosing the best implant orientation, radial or dorsal, the two different four-corner arthrodesis surgical constructs were virtually simulated on a 3D finite element model representing all major structures of the wrist. Two different realistic load sets were applied to the model, representing common tasks for the elderly. Findings: Results consistency was assessed by comparing with the literature the force magnitude computed on the carpal bones. The Von Mises stress distribution in the radial and dorsal plates were calculated. Stress concentration was located at the plate-screw interface for both surgical constructs, with a maximum stress value of 413 MPa for the dorsal plate compared to 326 MPa for the radial plate, meaning that the stress levels are more unfavourable in the dorsal approach. Interpretation: Although some bending stress was found in one load case, the radial plate was mechanically more robust in the other load case. Despite some limitations, this study provides, for the first time, quantified evidence that the newly developed radial surgical construct is mechanically as efficient as the dorsal surgical construct.
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- 2021
4. Estimation of joint contact pressure in the index finger using a hybrid finite element musculoskeletal approach
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Thomas Le Corroller, Benjamin Goislard de Monsabert, Barthélémy Faudot, Jean-Louis Milan, Laurent Vigouroux, Institut des Sciences du Mouvement Etienne Jules Marey (ISM), Centre National de la Recherche Scientifique (CNRS)-Aix Marseille Université (AMU), Institut du Mouvement et de l’appareil Locomoteur [Hôpital Sainte-Marguerite - APHM] (IML), Assistance Publique - Hôpitaux de Marseille (APHM)-Hôpital Sainte-Marguerite [CHU - APHM] (Hôpitaux Sud )-Rhumatologie [Sainte- Marguerite - APHM] ( Hôpitaux Sud), Assistance Publique - Hôpitaux de Marseille (APHM)-Hôpital Sainte-Marguerite [CHU - APHM] (Hôpitaux Sud ), Assistance Publique-Hôpitaux de Marseille (AP-HM), Aix Marseille Université (AMU)-Centre National de la Recherche Scientifique (CNRS), APHM, Institute for Locomotion, Department of Orthopaedics and Traumatology, St Marguerite Hospital, Marseille, France, APHM, Institute for Locomotion, Department of Radiology, St Marguerite Hospital, Marseille, France, Aix Marseille Univ, CNRS, ISM, Inst Movement Sci, Marseille, France, and Assistance Publique - Hôpitaux de Marseille (APHM)
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Male ,Computer science ,[SDV.IB.IMA]Life Sciences [q-bio]/Bioengineering/Imaging ,02 engineering and technology ,Osteoarthritis ,finite element analysis ,Metacarpophalangeal Joint ,Tendons ,0302 clinical medicine ,pinch grip task ,[PHYS.MECA.SOLID]Physics [physics]/Mechanics [physics]/Solid mechanics [physics.class-ph] ,Hand biomechanics ,ComputingMilieux_MISCELLANEOUS ,Hand Strength ,General Medicine ,Structural engineering ,Joint contact ,Finite element method ,Biomechanical Phenomena ,Computer Science Applications ,medicine.anatomical_structure ,Adult ,musculoskeletal diseases ,Coronavirus disease 2019 (COVID-19) ,Musculoskeletal Physiological Phenomena ,Posture ,0206 medical engineering ,Biomedical Engineering ,Bioengineering ,musculoskeletal model ,Models, Biological ,03 medical and health sciences ,joint contact pressure ,Finger Joint ,Pressure ,medicine ,Humans ,[PHYS.MECA.BIOM]Physics [physics]/Mechanics [physics]/Biomechanics [physics.med-ph] ,business.industry ,Cartilage ,Reproducibility of Results ,030229 sport sciences ,Index finger ,Stress distribution ,medicine.disease ,020601 biomedical engineering ,Human-Computer Interaction ,Hand joint ,Stress, Mechanical ,business - Abstract
International audience; The knowledge of local stress distribution in hand joints is crucial to understand injuries and osteoarthritis occurrence. However, determining cartilage contact stresses remains a challenge, requiring numerical models including both accurate anatomical components and realistic tendon force actuation. Contact forces in finger joints have frequently been calculated but little data is available on joint contact pressures. This study aimed to develop and assess a hybrid biomechanical model of the index finger to estimate in-vivo joint contact pressure during a static maximal strength pinch grip task. A finite element model including bones, cartilage, tendons, and ligaments was developed, with tendon force transmission based on a tendon-pulley system. This model was driven by realistic tendon forces estimated from a musculoskeletal model and motion capture data for six subjects. The hybrid model outputs agreed well with the experimental measurement of fingertip forces and literature data on the physiological distribution of tendon forces through the index finger. Mean contact pressures were 6.9 ± 2.7MPa, 6.2 ± 1.0 MPa and 7.2 ± 1.3MPa for distal, proximal interphalangeal and metacarpophalangeal joints, respectively. Two subjects had higher mean contact pressure in the distal joint than in the other two joints, suggesting a mechanical cause for the prevalence of osteoarthritis in the index distal joint. The inter-subject variability in joint contact pressure could be explained by different neuromuscular strategies employed for the task. This first application of an effective hybrid model to the index finger is promising for estimating hand joint stresses under daily grip tasks and simulating surgical procedures.
- Published
- 2020
5. Around-the-knee osteotomies part II: Surgical indications, techniques and outcomes - State of the art.
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Lott A, James MG, Kaarre J, Höger S, Kayaalp ME, Ollivier M, Getgood A, Hughes JD, and Musahl V
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- Humans, Biomechanical Phenomena, Femur surgery, Treatment Outcome, Bone Malalignment surgery, Osteotomy methods, Knee Joint surgery, Tibia surgery
- Abstract
Recent advances in surgical techniques and planning for knee-based osteotomies have led to improvements in addressing lower extremity malalignment. Part 1 of this review presented the biomechanical and clinical rationale of osteotomies, emphasizing the importance of osteotomies for restoring normal knee kinematics. In Part 2 of this review, indications, surgical technique and outcomes of osteotomies to correct coronal, sagittal and axial plane deformities will be examined. Traditional high tibial and distal femoral osteotomies will be discussed in addition to more recent advanced techniques including biplanar corrections and double-level osteotomies, as well as slope-correcting osteotomies. Patient-specific instrumentation and its use in more complex corrections will also be addressed., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Matthieu Ollivier reports a relationship with Newclip Technics that includes: consulting or advisory. Matthieu Ollivier reports a relationship with Stryker that includes: consulting or advisory. Matthieu Ollivier reports a relationship with Zimmer Inc that includes: consulting or advisory. Al Getgood is a board or committee member for ACL Study Group and the International Society of Arthroscopy, Knee Surgery, and Orthopaedic Sports Medicine (ISAKOS). Alan Getgood is a member of the editorial board of the American Journal of Sports Medicine and Knee Surgery, Sports Traumatology, Arthroscopy. Al Getgood reports research support from Aesculap/B. Braun, Arthrex, Inc, DePuy, Johnson & Johnson Company, Eupraxia Pharmaceuticals Inc, Musculoskeletal Transplant Foundation, and Ossur. Al Getgood has received IP royalties from Graymont Inc and are involved in companies like LinkX Robotics, Ostesys Robotics, Precision OS, and Spring Loaded Technologies Inc, with stock or stock options. Al Getgood also has also received paid consulting/presenting/speaking fees and research support from Smith & Nephew. Volker Musahl reports a relationship with Smith and Nephew Inc that includes: consulting or advisory, funding grants, and speaking and lecture fees. Volker Musahl reports a relationship with Arthrex Inc that includes: funding grants. Volker Musahl reports a relationship with DePuy Synthes that includes: funding grants. Volker Musahl reports a relationship with Newclip Technics that includes: consulting or advisory. Volker Musahl reports a relationship with International Society of Arthroscopy Knee Surgery and Orthopaedic Sports Medicine that includes: board membership. Volker Musahl has patent #9,949,684 issued to U.S. Patent. Matthieu Ollivier reports royalties from Newclip, Stryker and Zimmer. Volker Musahl is deputy editor-in-chief of Knee Surgery, Sports Traumatology, Arthroscopy (KSSTA). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)
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- 2024
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6. Ultra-high field magnetic resonance imaging of the quadriceps tendon enthesis in healthy subjects.
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Guenoun D, Wirth T, Roche D, Michel CP, Daudé P, Ogier AC, Chagnaud C, Mattei JP, Pini L, Guye M, Ollivier M, Bendahan D, and Guis S
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- Humans, Healthy Volunteers, Imaging, Three-Dimensional methods, Magnetic Resonance Imaging methods, Tendons diagnostic imaging, Arthritis, Rheumatoid
- Abstract
Purpose: Although enthesitis is a hallmark of several rheumatologic conditions, current imaging methods are still unable to characterize entheses changes because of the corresponding short transverse relaxation times (T2). A growing number of MR studies have used Ultra-High Field (UHF) MRI in order to assess low-T2 tissues e.g., tendon but never in humans. The purpose of the present study was to assess in vivo the enthesis of the quadriceps tendon in healthy subjects using UHF MRI., Methods: Eleven healthy subjects volunteered in an osteoarthritis imaging study. The inclusion criteria were: no knee trauma, Lequesne index = 0, less than 3 h of sport activities per week, and Kellgren and Lawrence grade = 0. 3D MR images were acquired at 7 T using GRE sequences and a T2* mapping. Regions of interest i.e., trabecular bone, subchondral bone, enthesis, and tendon body were identified, and T2* values were quantified and compared., Results: Quadriceps tendon enthesis was visible as a hyper-intense signal. The largest and the lowest T2* values were quantified in the subchondral bone region and the tendon body respectively. T2* value within subchondral bone was significantly higher than T2* value within the enthesis. T2* in subchondral bone region was significantly higher than the whole tendon body T2*., Conclusion: A T2* gradient was observed along the axis from the enthesis toward the tendon body. It illustrates different water biophysical properties. These results provide normative values which could be used in the field of inflammatory rheumatologic diseases and mechanical disorders affecting the tendon., (© 2023. The Author(s), under exclusive licence to Springer-Verlag France SAS, part of Springer Nature.)
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- 2023
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7. Intelligent innovations for our journal's path forward.
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Dahmen J, Kayaalp ME, Winkler PW, Ollivier M, Pareek A, Karlsson J, and Hirschmann MT
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- 2023
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8. Artificial intelligence bot ChatGPT in medical research: the potential game changer as a double-edged sword.
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Dahmen J, Kayaalp ME, Ollivier M, Pareek A, Hirschmann MT, Karlsson J, and Winkler PW
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- Humans, Artificial Intelligence, Biomedical Research
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- 2023
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9. Vertebral trabecular bone texture analysis in opportunistic MRI and CT scan can distinguish patients with and without osteoporotic vertebral fracture: A preliminary study.
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Poullain F, Champsaur P, Pauly V, Knoepflin P, Le Corroller T, Creze M, Pithioux M, Bendahan D, and Guenoun D
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- Humans, Retrospective Studies, Cancellous Bone, Reproducibility of Results, Absorptiometry, Photon methods, Mass Screening methods, Bone Density, Tomography, X-Ray Computed methods, Lumbar Vertebrae diagnostic imaging, Lumbar Vertebrae injuries, Spinal Fractures diagnostic imaging, Osteoporotic Fractures diagnostic imaging
- Abstract
Purpose: To investigate the potential of texture parameters from opportunistic MRI and CT for the detection of patients with vertebral fragility fracture, to design a decision tree and to compute a Random Forest analysis for the prediction of fracture risk., Methods: One hundred and eighty vertebrae of sixty patients with at least one (30) or without (30) a fragility fracture were retrospectively assessed. Patients had a DXA, an MRI and a CT scan from the three first lumbar vertebrae. Vertebrae texture analysis was performed in routine abdominal or lumbar CT and lumbar MRI using 1st and 2nd order texture parameters. Hounsfield Unit Bone density (HU BD) was also measured on CT-scan images., Results: Twelve texture parameters, Z-score and HU BD were significantly different between the two groups whereas T score and BMD were not. The inter observer reproducibility was good to excellent. Decision tree showed that age and HU BD were the most relevant factors to predict the fracture risk with a 93 % sensitivity and 56 % specificity. AUC was 0.91 in MRI and 0.92 in CT-scan using the Random Forest analysis. The corresponding sensitivity and specificity were 72 % and 93 % in MRI and 83 and 89 % in CT., Conclusions: This study is the first to compare texture indices computed from opportunistic CT and MR images. Age and HU-BD together with selected texture parameters could be used to assess risk fracture. Machine learning algorithm can detect fracture risk in opportunistic CT and MR imaging and might be of high interest for the diagnosis of osteoporosis., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)
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- 2023
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10. Correction to: Current state of dental informatics in the field of health information systems: a scoping review.
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Ballester B, Bukiet F, and Dufour JC
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- 2022
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11. Suitability of Reusing Pre-Doctoral Student Activity Data from an Educational Information System for Quality Measures of Caries Risk.
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Ballester B, Casazza E, Bukiet F, and Dufour JC
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- Dental Caries Susceptibility, Humans, Information Systems, ROC Curve, Retrospective Studies, Students, Dental Caries diagnosis, Dental Caries epidemiology, Dental Caries prevention & control, Quality Indicators, Health Care
- Abstract
Dental caries management requires individualized follow-up and prophylaxis based on patients' caries risk (PCR). In large pre-doctoral clinics, the use of institutional quality measures (QMs) is essential to control the quality of patient follow-up and to evaluate the need for improvement measures. The aim of this retrospective study was to evaluate the suitability of reusing student activity data for the development of QMs of caries risk. Two approaches for predicting PCR using student activity data were evaluated and compared. The first approach used the procedure codes recommended by the Dental Quality Alliance and the second used these same codes along with three educational codes. The sensitivity, specificity, overall accuracy of the two approaches were evaluated. A Receiver Operating Characteristic (ROC) curve analysis was carried out, and the areas under the ROC curve of the two approaches were compared using Delong's test. A two-tailed P value ≤0.05 was considered statistically significant. While the two approaches were able to correctly predict PCR, the approach using both procedure and educational codes showed better predictive performance. The reuse of student activity data is an easy and robust method for the development of QMs of caries risk that can help improve monitoring and quality of patient care.
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- 2022
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12. ECHO: An Information System for the Monitoring and Evaluation of Dental Student Activity in a Pre-Doctoral Clinic.
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Ballester B, Bukiet F, and Dufour JC
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- France, Humans, Information Systems, Surveys and Questionnaires, Education, Dental, Students, Dental
- Abstract
The main goal of dental education is to develop health professionals who will maintain and improve the oral health of patients. This requires the quantitative and qualitative assessment of dental student activity. The aim of this work is to describe the ECHO information system that was developed at Timone Hospital (France) for the monitoring and evaluation of dental student activity and to present the results of a qualitative evaluation of student perceptions of this system. According to the analysis of the UML model of care-related procedures and data, the pre-existing process of student evaluation was characterized by redundancy between administrative and educational data. ECHO was developed in PHP/MySQL and designed to centralize the two types of data in a unified computerized process. The qualitative evaluation of dental student perceptions of ECHO was performed using an anonymous online Google Form questionnaire. Among the respondents (102/254 students), 96% stated that ECHO is easy to use, 86% that it saves time, and 81% that it gives them a better overview of their activity. After several years of use, ECHO has solved many of the difficulties related to the use of internship paper booklets, while also providing a documentary database of the activities of our dental department. The student activity data stored in ECHO are directly accessible by faculty members and can be reused to facilitate departmental management and research and to improve patient follow-up.
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- 2022
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13. Current state of dental informatics in the field of health information systems: a scoping review.
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Benoit B, Frédéric B, and Jean-Charles D
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- Dental Informatics, Dentists, Humans, Professional Role, Health Information Systems
- Abstract
Background: Over the past 50 years, dental informatics has developed significantly in the field of health information systems. Accordingly, several studies have been conducted on standardized clinical coding systems, data capture, and clinical data reuse in dentistry., Methods: Based on the definition of health information systems, the literature search was divided into three specific sub-searches: "standardized clinical coding systems," "data capture," and "reuse of routine patient care data." PubMed and Web of Science were searched for peer-reviewed articles. The review was conducted following the PRISMA-ScR protocol., Results: A total of 44 articles were identified for inclusion in the review. Of these, 15 were related to "standardized clinical coding systems," 15 to "data capture," and 14 to "reuse of routine patient care data." Articles related to standardized clinical coding systems focused on the design and/or development of proposed systems, on their evaluation and validation, on their adoption in academic settings, and on user perception. Articles related to data capture addressed the issue of data completeness, evaluated user interfaces and workflow integration, and proposed technical solutions. Finally, articles related to reuse of routine patient care data focused on clinical decision support systems centered on patient care, institutional or population-based health monitoring support systems, and clinical research., Conclusions: While the development of health information systems, and especially standardized clinical coding systems, has led to significant progress in research and quality measures, most reviewed articles were published in the US. Clinical decision support systems that reuse EDR data have been little studied. Likewise, few studies have examined the working environment of dental practitioners or the pedagogical value of using health information systems in dentistry., (© 2022. The Author(s).)
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- 2022
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14. Intradiscal oxygen-ozone therapy for the treatment of symptomatic lumbar disc herniation: A preliminary study.
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Simon C, Le Corroller T, Pauly V, Creze M, Champsaur P, and Guenoun D
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- Humans, Lumbar Vertebrae diagnostic imaging, Lumbar Vertebrae surgery, Oxygen therapeutic use, Prospective Studies, Treatment Outcome, Intervertebral Disc Displacement diagnostic imaging, Intervertebral Disc Displacement drug therapy, Ozone therapeutic use
- Abstract
Purpose: To assess safety and effectiveness of computed tomography (CT)-guided intradiscal oxygen-ozone therapy (O
2 -O3 therapy) for the treatment of symptomatic lumbar disc herniation and radiological changes., Materials and Methods: This study was conducted in twenty patients presenting lumbar disc herniation with resistant lumbar or lumbar radicular pain They underwent intradiscal oxygen-ozone therapy under CT guidance. They were treated at one- or two-disc levels, representing a total of 24 discs treated. MR imaging examinations were obtained before treatment and 2 months post-procedure to analyse treatment-related disc modifications including modification of the surfaces of the disc and of the herniated disc, and the variations in disc height according to the disc height index. Clinical outcomes were assessed using the visual analogue scale (VAS) to evaluate the severity of pain before the procedure, at primary (2 months) and at secondary (12 months) follow-ups., Results: All the procedures were technically successful. The median VAS scores were 7.95 before the procedure, 3.9 at 2 months and 2.95 at 12 months. MRI analysis showed a significant decrease in herniation size at 2 months (-20%, p = 0.008). No immediate or late complications were observed. Only three patients (13.6%) underwent lumbar spine microdiscectomy in the year following ozone therapy. The treatment appeared to be more effective in cases of nerve root symptomatology., Conclusion: This study suggests that intradiscal O2 -O3 therapy is safe and effective for the treatment of lumbar disc herniation associated with resistant lumbar or lumbar radicular pain., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interest., (Copyright © 2021 Elsevier Masson SAS. All rights reserved.)- Published
- 2022
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15. Current strategies for conservative endodontic access cavity preparation techniques-systematic review, meta-analysis, and decision-making protocol.
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Ballester B, Giraud T, Ahmed HMA, Nabhan MS, Bukiet F, and Guivarc'h M
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- Dental Care, Dental Pulp Cavity, Humans, Meta-Analysis as Topic, Molar, Root Canal Preparation, Root Canal Therapy, Systematic Reviews as Topic, Dental Cavity Preparation, Tooth Fractures
- Abstract
Objectives: To assess related studies and discuss the clinical implications of endodontic access cavity (AC) designs., Materials and Methods: A systematic review of studies comparing the fracture resistance and/or endodontic outcomes between different AC designs was conducted in two electronic search databases (PubMed and Web of Science) following the PRISMA guidelines. Study selection, data extraction, and quality assessment were performed. Meta-analyses were undertaken for fracture resistance and root canal detection, with the level of significance set at 0.05 (P = 0.05)., Results: A total of 33 articles were included in this systematic review. The global evaluation of the risk of bias in the included studies was assessed as moderate, and the level of evidence was rated as low. Four types of AC designs were categorized: traditional (TradAC), conservative (ConsAC), ultraconservative (UltraAC), and truss (TrussAC). Their impact on fracture resistance, cleaning/disinfection, procedural errors, root canal detection, treatment time, apical debris extrusion, and root canal filling was discussed. Meta-analysis showed that compared to TradAC, (i) there is a significant higher fracture resistance of teeth with ConsAC, TrussAC, or ConsAC/TrussAC when all marginal ridges are preserved (P < 0.05), (ii) there is no significant effect of the type of AC on the fracture resistance of teeth when one or two marginal ridges are lost (P > 0.05), and (iii) there is a significantly higher risk of undetected canals with ConsAC if not assisted by dental operating microscope and ultrasonic troughing (P < 0.05)., Conclusions: Decreasing the AC extent does not necessarily present mechanical and biological advantages especially when one or more surfaces of the tooth structure are lost. To date, the evidence available does not support the application of TrussAC. UltraAC might be applied in limited occasions., Clinical Relevance: Maintaining the extent of AC design as small as practical without jeopardizing the root canal treatment quality remains a pragmatic recommendation. Different criteria can guide the practitioner for the optimal extent of AC outline form which varies from case to case., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)
- Published
- 2021
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16. Identification and validation of novel biomarkers and therapeutics for pulpitis using connectivity mapping.
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Al-Natour B, Rankin R, McKenna R, McMillan H, Zhang SD, About I, Khan AA, Galicia JC, Lundy FT, and El-Karim IA
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- Biomarkers, Computational Biology, Dental Pulp, Humans, Real-Time Polymerase Chain Reaction, Pulpitis drug therapy
- Abstract
Aim: To create an irreversible pulpitis gene signature from microarray data of healthy and inflamed dental pulps, followed by a bioinformatics approach using connectivity mapping to identify therapeutic compounds that could potentially treat pulpitis., Methodology: The Gene Expression Omnibus (GEO) database, an international public repository of genomics data sets, was searched for human microarray datasets assessing pulpitis. An irreversible pulpitis gene expression signature was generated by differential expression analysis. The statistically significant connectivity map (ssCMap) method was used to identify compounds with a highly correlating gene expression pattern. qPCR was used to validate novel pulpitis genes. An ex vivo pulpitis model was used to test the effects of the compounds identified, and the level of inflammatory cytokines was measured with qPCR, ELISA and multiplex array. Means were compared using the t-test or ANOVA with the level of significance set at p ≤ .05., Results: Pulpitis gene signatures were created using differential gene expression analysis at cutoff points p = .0001 and .000018. Top upregulated genes were selected as potential pulpitis biomarkers. Among these, IL8, IL6 and MMP9 were previously identified as pulpitis biomarkers. Novel upregulated genes, chemokine (C-C motif) ligand 21 (CCL21), metallothionein 1H (MT1H) and aquaporin 9 (AQP9) were validated in the pulp tissue of teeth clinically diagnosed with irreversible pulpitis using qPCR. ssCMap analysis identified fluvastatin (Statin) and dequalinium chloride (Quaternary ammonium) as compounds with the strongest correlation to the gene signatures (p = .0001). Fluvastatin reduced IL8, IL6, CCL21, AQP9 (p < .001) and MMP9 (p < .05) in the ex vivo pulpitis model, while dequalinium chloride reduced AQP9 (p < .001) but had no significant effect on the other biomarkers., Conclusions: AQP9, MT1H and CCL21 were identified and validated as novel biomarkers for pulpitis. Fluvastatin and dequalinium chloride identified by the ssCMap as potential therapeutics for pulpitis reduced selected pulpitis biomarkers in an ex vivo pulpitis model. In vivo testing of these licenced drugs is warranted., (© 2021 The Authors. International Endodontic Journal published by John Wiley & Sons Ltd on behalf of British Endodontic Society.)
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- 2021
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17. Endogenous Mas-related G-protein-coupled receptor X1 activates and sensitizes TRPA1 in a human model of peripheral nerves.
- Author
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McMillan H, Lundy FT, Dunne OM, Al-Natour B, Jeanneau C, About I, Curtis TM, and El Karim I
- Subjects
- Dental Pulp cytology, Humans, Nociception, Peripheral Nerves cytology, Stem Cells cytology, Dental Pulp metabolism, Membrane Potentials, Peripheral Nerves metabolism, Receptors, G-Protein-Coupled metabolism, Stem Cells metabolism, TRPA1 Cation Channel metabolism
- Abstract
Mas-related G-protein-coupled receptor X1 (MrgprX1) is a human-specific Mrgpr and its expression is restricted to primary sensory neurons. However, its role in nociception and pain signaling pathways is largely unknown. This study aims to investigate a role for MrgprX1 in nociception via interaction with the pain receptor, Transient Receptor Potential Ankyrin 1 (TRPA1), using in-vitro and in-vivo human neuronal models. MrgprX1 protein expression in human trigeminal nociceptors was investigated by the immunolabeling of the dental pulp and cultured peripheral neuronal equivalent (PNE) cells. MrgprX1 receptor signaling was monitored by Fura-2-based Ca
2+ imaging using PNEs and membrane potential responses were measured using FluoVoltTM . Immunofluorescent staining revealed MrgprX1 expression in-vivo in dental afferents, which was more intense in inflamed compared to healthy dental pulps. Endogenous MrgprX1 protein expression was confirmed in the in-vitro human PNE model. MrgprX1 receptor signaling and the mechanisms through which it couples to TRPA1 were studied by Ca2+ imaging. Results showed that MrgprX1 activates TRPA1 and induces membrane depolarization in a TRPA1 dependent manner. In addition, MrgprX1 sensitizes TRPA1 to agonist stimulation via Protein Kinase C (PKC). The activation and sensitization of TRPA1 by MrgprX1 in a model of human nerves suggests an important role for this receptor in the modulation of nociception., (© 2021 The Authors. The FASEB Journal published by Wiley Periodicals LLC on behalf of Federation of American Societies for Experimental Biology.)- Published
- 2021
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18. Complement activation links inflammation to dental tissue regeneration.
- Author
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Bergmann M, Jeanneau C, Giraud T, Richard G, and About I
- Subjects
- Cell Differentiation, Fibroblasts, Humans, Inflammation, Stem Cells, Complement Activation, Dental Pulp
- Abstract
Objectives: Complement is an efficient plasma immune surveillance system. It initiates inflammation by inducing vascular modifications and attracting immune cells expressing Complement receptors. Investigating Complement receptors in non-immune cells pointed out Complement implication in the regeneration of tissue such as liver, skin, or bone. This review will shed the light on Complement implication in the initial steps of dental tissue regeneration., Materials and Methods: Review of literature was conducted on Complement local expression and implication in oral tissue regeneration in vivo and in vitro., Results: Recent data reported expression of Complement receptors and soluble proteins in dental tissues. Cultured pulp fibroblasts secrete all Complement components. Complement C3b and MAC have been shown to control bacteria growth in the dental pulp while C3a and C5a are involved in the initial steps of pulp regeneration. Indeed, C3a induces pulp stem cell/fibroblast proliferation, and fibroblast recruitment, while C5a induces neurite growth, guides stem cell recruitment, and odontoblastic differentiation. Similarly, cultured periodontal ligament cells produce C5a which induces bone marrow mesenchymal stem cell recruitment., Conclusions: Overall, this review highlights that local Complement synthesis in dental tissues plays a major role, not only in eliminating bacteria but also in the initial steps of dental tissue regeneration, thus providing a link between dental tissue inflammation and regeneration., Clinical Relevance: Complement provides an explanation for understanding why inflammation preceeds regeneration. This may also provide a biological rational for understanding the reported success conservative management of mature permanent teeth with carious pulp exposure.
- Published
- 2020
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19. Toward a Mathematical Modeling of Diseases' Impact on Bone Remodeling: Technical Review.
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Ait Oumghar I, Barkaoui A, and Chabrand P
- Abstract
A wide variety of bone diseases have hitherto been discovered, such as osteoporosis, Paget's disease, osteopetrosis, and metastatic bone disease, which are not well defined in terms of changes in biochemical and mechanobiological regulatory factors. Some of these diseases are secondary to other pathologies, including cancer, or to some clinical treatments. To better understand bone behavior and prevent its deterioration, bone biomechanics have been the subject of mathematical modeling that exponentially increased over the last years. These models are becoming increasingly complex. The current paper provides a timely and critical analysis of previously developed bone remodeling mathematical models, particularly those addressing bone diseases. Besides, mechanistic pharmacokinetic/pharmacodynamic (PK/PD) models, which englobe bone disease and its treatment's effect on bone health. Therefore, the review starts by presenting bone remodeling cycle and mathematical models describing this process, followed by introducing some bone diseases and discussing models of pathological mechanisms affecting bone, and concludes with exhibiting the available bone treatment procedures considered in the PK/PD models., (Copyright © 2020 Ait Oumghar, Barkaoui and Chabrand.)
- Published
- 2020
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20. Preclinical effectiveness of an experimental tricalcium silicate cement on pulpal repair.
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Li X, Pedano MS, Li S, Sun Z, Jeanneau C, About I, Hauben E, Chen Z, Van Landuyt K, and Van Meerbeek B
- Subjects
- Cell Differentiation, Dental Pulp, Glass Ionomer Cements, Humans, Odontoblasts, Silicates pharmacology, Calcium Compounds pharmacology, Pulp Capping and Pulpectomy Agents
- Abstract
Objectives: To investigate the pulpal repair potential of an experimental zirconium-oxide containing tricalcium-silicate cement, referred to as 'TCS 50'., Materials and Methods: The effect of TCS 50 on viability, proliferation, migration, and odontoblastic differentiation of human dental pulp cells (HDPCs) was assessed using XTT assay, in-vitro wound healing assay and RT-PCR, respectively. Additionally, the pulp-capping potential was evaluated using a vital human tooth model. Statistical analysis was performed using non-parametric Kruskal-Wallis test and post-hoc test (Mann-Whitney U test). The tests were performed at a significance level of α = 0.05., Results: The effect of TCS 50 towards HDPCs was dose dependent. Undiluted TCS 50 extract showed no immediate adverse impact on cell viability (p > .05); however, it significantly inhibited proliferation and migration of HDPCs (p < .05). A 25% diluted TCS 50 extract showed no significant effect on cell viability, proliferation or migration (p > .05), and it significantly enhanced odontoblastic differentiation of HDPCs (p < .05). In pulps capped with TCS 50 for both 2 and 4 weeks, H&E staining revealed a normal morphology of pulp tissue; mineralized foci with cellular components entrapped in the matrix were formed underneath the exposure site. Collagen I expression was weak within the matrix of mineralized foci, while the expression of nestin was positive for entrapped cellular components within the mineralized foci, indicating that the formed mineralized foci corresponded to an initial form of reparative dentin formation., Conclusion: TCS 50 is capable of generating an early pulp-healing reaction and therefore could serve as a promising pulp-capping agent., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2020
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21. Xenogeneic bone filling materials modulate mesenchymal stem cell recruitment: role of the Complement C5a.
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Jeanneau C, Le Fournis C, and About I
- Subjects
- Animals, Cattle, Cells, Cultured, Horses, Swine, Bone Regeneration, Complement C5a, Mesenchymal Stem Cells, Periodontal Ligament physiology
- Abstract
Objectives: When bone filling materials are applied onto the periodontal tissues in vivo, they interact with the injured periodontal ligament (PDL) tissue and modulate its activity. This may lead to mesenchymal stem cells (MSCs) recruitment from bone marrow and initiate bone regeneration. Our hypothesis is that the filling materials affect PDL cells and MSCs functional activities by modulating PDL C5a secretion and subsequent MSCs proliferation and recruitment., Materials and Methods: Materials' extracts were prepared from 3 bone-grafting materials: Gen-Os
® of equine and porcine origins and bovine Bio-Oss® . Expression and secretion of C5a protein by injured PDL cells were investigated by RT-PCR and ELISA. MSCs proliferation was analyzed by MTT assay. C5a binding to MSCs C5aR and its phosphorylation was studied by ELISA. C5a implication in MSCs recruitment toward injured PDL cells was investigated using Boyden chambers., Results: MSCs proliferation significantly increased with Gen-Os® materials but significantly decreased with Bio-Oss® . C5a secretion slightly increased with Bio-Oss® while its level doubled with Gen-Os® materials. C5a fixation on MSCs C5aR and its phosphorylation significantly increased with Gen-Os® materials but not with Bio-Oss® . MSCs recruitment toward injured PDL cells increased with the three materials but was significantly higher with Gen-Os® materials than with Bio-Oss® . Adding C5a antagonist inhibited MSCs recruitment demonstrating a C5a-mediated migration., Conclusions: Injured PDL cells secrete C5a leading MSCs proliferation and recruitment to the PDL injured cells. Gen-Os® materials enhanced both C5a secretion by injured PDL cells and MSCs recruitment. Bio-Oss® inhibited MSCs and was less efficient than Gen-Os® materials in inducing MSCs recruitment., Clinical Relevance: Within the limits of this study in vitro, Gen-Os® filling materials have a higher potential than Bio-Oss® on MSCs proliferation and C5a-dependent recruitment to the PDL injury site and the subsequent bone regeneration.- Published
- 2020
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22. A connectivity mapping approach predicted acetylsalicylic acid (aspirin) to induce osteo/odontogenic differentiation of dental pulp cells.
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Rankin R, Lundy FT, Schock BC, Zhang SD, Al-Natour B, About I, Irwin C, Linden GJ, and El-Karim IA
- Subjects
- Alkaline Phosphatase, Cell Differentiation, Cell Proliferation, Cells, Cultured, Humans, Odontogenesis, Aspirin, Dental Pulp
- Abstract
Aim: To use connectivity mapping, a bioinformatics approach, to identify compounds that could induce odontogenic differentiation of dental pulp cells (DPCs) and to experimentally validate this effect. A subsidiary aim was to investigate the anti-inflammatory effect of any identified compound., Methodology: The Gene Expression Omnibus (GEO) database was searched for microarray data sets assessing odontogenic differentiation of human DPCs. An odontogenic gene expression signature was generated by differential expression analysis. The statistical significant connectivity map (ssCMap) method was used to identify compounds with a highly correlating gene expression pattern. DPCs were treated with the compound identified, and osteo/odontogenic differentiation was assessed by Alizarin red staining, alkaline phosphatase activity and expression of osteo/odontogenic genes ALPL, RUNX2, COL1A1, DSPP, DMP1 and SPP1 by RT-PCR. The anti-inflammatory effect of the compound was assessed using an ex vivo pulpitis model, and cytokine levels were measured with multiplex assay. Means were compared using the t-test or ANOVA followed by a Bonferroni post hoc test with the level of significance set at P ≤ 0.05., Results: The GEO database search identified a specific gene expression signature for osteo/odontogenic differentiation. Analysis using ssCMap found that acetylsalicylic acid [(ASA)/aspirin] was the drug with the strongest correlation with that gene signature. The treatment of DPCs with 0.05 mmol L
-1 ASA showed increased alkaline phosphatase activity (P < 0.001), mineralization (P < 0.05), and increased the expression of the osteo/odontogenic genes, DMP1 and DSPP (P < 0.05). Low concentration (0.05 mmol L-1 ) ASA reduced inflammatory cytokines IL-6 (P < 0.001), CCL21 (P < 0.05) and MMP-9 (P < 0.05) in an ex vivo pulpitis model., Conclusions: Connectivity mapping, a web-based informatics method, was successfully used to identify aspirin as a candidate drug that could modulate the differentiation of DPCs. Aspirin was shown to induce odontogenic differentiation in DPCs in vitro and this, together with its anti-inflammatory effects, makes it a potential candidate for vital pulp therapies., (© 2020 International Endodontic Journal. Published by John Wiley & Sons Ltd.)- Published
- 2020
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23. Canal Transportation and Centring Ability of Reciproc and Reciproc Blue With or Without Use of Glide Path Instruments: A CBCT Study.
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Hage W, Zogheib C, Bukiet F, Sfeir G, Khalil I, Gergi R, and Naaman A
- Subjects
- Equipment Design, Humans, Root Canal Preparation methods, Maxilla, Molar, Root Canal Preparation instrumentation, Root Canal Therapy instrumentation, Spiral Cone-Beam Computed Tomography methods, Tooth Apex, X-Ray Microtomography methods
- Abstract
Objective: The objective of this ex vivo study was to evaluate canal transportation and centring ability of Reciproc and Reciproc blue systems in curved root canals with or without prior use of PathFile rotary system (PF) using Cone Beam Computed Tomography (CBCT)., Methods: One hundred and twenty curved root canals from maxillary and mandibular premolars were selected. Canals were divided randomly into 4 groups (n=30): Reciproc 25 (R25), (PF+R25), Reciproc Blue 25 (RB25), (PF+RB 25). Specimens were scanned before and after root canal preparation. Using CBCT, root canal transportation and centring ability was assessed by measuring the shortest distance from the edge of uninstrumented canal to the periphery of the root (mesial and distal) before and after preparation. Data were analysed using a one-way analysis of variance and Tukey test. The p value was set at 0.05., Results: Less transportation and better centring ability occurred when PF was used before R25 or RB25 (P<0.0001). There was no significant difference between R25 and RB25 groups., Conclusion: Using PF before R25 and RB25 resulted in less root canal transportation and better centring ability. The specific thermo-mechanical treatment of RB25 did not provide better results when compared to R25., Competing Interests: Conflict of interest: The authors declare no conflict of interest., (Copyright: © 2020 European Endodontic Journal.)
- Published
- 2020
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24. Investigating unset endodontic sealers' eugenol and hydrocortisone roles in modulating the initial steps of inflammation.
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Jeanneau C, Giraud T, Milan JL, and About I
- Subjects
- Drug Combinations, Endothelial Cells, Humans, Zinc Oxide-Eugenol Cement, Eugenol therapeutic use, Hydrocortisone therapeutic use, Inflammation drug therapy, Root Canal Filling Materials
- Abstract
Introduction: Endodontic treatment success is achieved not only when the cement provides a hermetic seal but also when the injured periapical tissue is regenerated. However, an exaggerated inflammatory reaction hinders tissue regeneration and it has been shown that dental materials affect the inflammatory response through modulation of cytokine secretion. This work was set to investigate the effects of the presence of hydrocortisone in zinc oxide eugenol sealers (Endomethasone N) on modulating the initial steps of inflammation in vitro., Material and Methods: Hydrocortisone and eugenol leaching from Endomethasone N and Pulp Canal Sealer (PCS) were quantified by ELISA and spectrofluorometry, respectively. The effects of Endomethasone N and Pulp Canal Sealer were studied on lipopolysaccharides (LPS)-stimulated human periodontal ligament (hPDL) cells. Cytokine (IL-6, TNF-α) secretion from cells was quantified by ELISA. Inflammatory cell (THP-1) adhesion to activated endothelial cells, their migration and activation were studied in vitro., Results: Endomethasone N decreased secretion of IL-6 and TNF-α from hPDL cells. THP-1 adhesion to activated endothelial cells (HUVECs) and migration significantly decreased with Endomethasone N while no effect was observed with PCS. Activation of THP-1 decreased with both materials' extracts but was significantly lower with Endomethasone N than with PCS., Conclusion: These results performed in vitro show that Endomethasone N anti-inflammatory effects are due to the presence of hydrocortisone., Clinical Relevance: Endomethasone N has potential local anti-inflammatory effects which appear to be due to its hydrocortisone rather than eugenol content. Decreasing the inflammatory response is a pre-requisite to initiate the periapical healing.
- Published
- 2020
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25. Understanding Thoracic Spine Morphology, Shape, and Proportionality.
- Author
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Lafage R, Steinberger J, Pesenti S, Assi A, Elysee JC, Iyer S, Lenke LG, Schwab FJ, Kim HJ, and Lafage V
- Subjects
- Female, Humans, Male, Middle Aged, Radiography, Thoracic, Retrospective Studies, Thoracic Vertebrae anatomy & histology, Thoracic Vertebrae diagnostic imaging, Thoracic Vertebrae physiology
- Abstract
Study Design: Retrospective review., Objective: The aim of this study was to describe thoracic kyphosis (TK) in a normal asymptomatic population and to evaluate the association between TK magnitude and its shape., Summary of Background Data: Understanding spinal anatomy requires a three-dimensional appreciation of the spine's shape, morphology, and proportions. The customary definition of TK is the angle between T4 and T12. However, little is known on the actual shape of TK in adults., Methods: Asymptomatic volunteers were recruited; demographic data along with full-body standing radiographs were recorded. Radiographic data such as T1-12 and T4-12 angles were collected. Maximum TK and vertebral orientation/tilt were also collected, in addition to cumulative TK and Centered Kyphosis at T7. The cohort was stratified by T1-12 value (<40°, 40°-60°, and>60°) and comparisons and regressions were performed afterward., Results: One hundred nineteen subjects were included (average age 50.8 yrs, 81 female). Mean T1-12 kyphosis was 49.5°, mean T4-12 kyphosis 41.5°, and mean maximum TK was 52.6°. T1 was the most anteriorly tilted vertebra, L1 the most posteriorly tilted; T7 was horizontal, independently of T1-12 value or age. Cumulative kyphosis analysis revealed that the apex of kyphosis was located at T6-T7. Regression analysis predicting the value and the percentage of T1-7 both yielded T1-12 as a predictor (Adj. r = 0.32, Adj. r = 0.13)., Conclusion: Changes in kyphosis distribution in an asymptomatic population suggest that TK is not a simple circle arc: with low TK, 2/3 of the kyphosis is located in the upper part and when TK increases, the distribution of kyphosis will be symmetric around T7. It is possible to predict the amount of kyphosis in the upper part using total kyphosis value. This could help estimate preoperative compensation and predict reciprocal change., Level of Evidence: 3.
- Published
- 2020
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26. An international survey on the use of calcium silicate-based sealers in non-surgical endodontic treatment.
- Author
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Guivarc'h M, Jeanneau C, Giraud T, Pommel L, About I, Azim AA, and Bukiet F
- Subjects
- Adult, Aged, Female, Humans, Male, Middle Aged, Root Canal Obturation, Surveys and Questionnaires, Calcium, Calcium Compounds, Root Canal Filling Materials, Silicates
- Abstract
Objectives: To gain insight on the current clinical usage of bioceramic root canal sealers (BRCS) by general dental practitioners (GDPs) and endodontic practitioners (EPs) and to determine if BRCS clinical application is in accordance with the best available evidence., Material and Methods: An online questionnaire of 18 questions addressing BRCS was proposed to 2335 dentists via a web-based educational forum. Participants were asked about socio-demographic data, clinical practice with BRCS, and their motivation for using BRCS. Statistical analysis (chi-squared test or Fisher's exact test) was applied, as appropriate, to assess the association between the variable categories (p value < 0.05)., Results: The response rate was 28.91%. Among respondents, 94.8% knew BRCS (EPs more than GDPs, p < 0.05) and 51.70% were using BRCS. The primary reason for using BRCS was their belief of its improved properties (87.7%). Among BRCS users, single-cone technique (SCT) was the most employed obturation method (63.3%) which was more applied by GDPs (p < 0.05); EPs utilized more of the thermoplasticized obturation techniques (p < 0.05). A proportion of 38.4% of BRCS users indicated the usage of SCT with BRCS regardless of the root canal anatomy (GDPs more than EPs p < 0.05) and 55.6% considered that BRCS may influence their ability to re-establish apical patency during retreatment (GDPs more than EPs p < 0.05)., Conclusions: This study highlights wide variation in the clinical use of BRCS which is not in accordance with the current literature., Clinical Relevance: This inconsistency among EPs and GDPs on BRCS clinical application requires further clarifications to better standardize their use and improve their future evaluation.
- Published
- 2020
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27. Compositional and mechanical properties of growing cortical bone tissue: a study of the human fibula.
- Author
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Lefèvre E, Farlay D, Bala Y, Subtil F, Wolfram U, Rizzo S, Baron C, Zysset P, Pithioux M, and Follet H
- Subjects
- Adolescent, Aged, Aged, 80 and over, Aging metabolism, Biomechanical Phenomena, Calcification, Physiologic, Carbon analysis, Child, Child, Preschool, Collagen analysis, Cortical Bone chemistry, Cortical Bone diagnostic imaging, Cortical Bone ultrastructure, Crystallization, Extracellular Matrix physiology, Female, Fibula chemistry, Fibula diagnostic imaging, Fibula ultrastructure, Haversian System diagnostic imaging, Haversian System growth & development, Haversian System ultrastructure, Humans, Male, Middle Aged, Minerals analysis, Models, Biological, Stress, Mechanical, Cortical Bone growth & development, Fibula growth & development
- Abstract
Human cortical bone contains two types of tissue: osteonal and interstitial tissue. Growing bone is not well-known in terms of its intrinsic material properties. To date, distinctions between the mechanical properties of osteonal and interstitial regions have not been investigated in juvenile bone and compared to adult bone in a combined dataset. In this work, cortical bone samples obtained from fibulae of 13 juveniles patients (4 to 18 years old) during corrective surgery and from 17 adult donors (50 to 95 years old) were analyzed. Microindentation was used to assess the mechanical properties of the extracellular matrix, quantitative microradiography was used to measure the degree of bone mineralization (DMB), and Fourier transform infrared microspectroscopy was used to evaluate the physicochemical modifications of bone composition (organic versus mineral matrix). Juvenile and adult osteonal and interstitial regions were analyzed for DMB, crystallinity, mineral to organic matrix ratio, mineral maturity, collagen maturity, carbonation, indentation modulus, indicators of yield strain and tissue ductility using a mixed model. We found that the intrinsic properties of the juvenile bone were not all inferior to those of the adult bone. Mechanical properties were also differently explained in juvenile and adult groups. The study shows that different intrinsic properties should be used in case of juvenile bone investigation.
- Published
- 2019
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28. Estimation of the elastic modulus of child cortical bone specimens via microindentation.
- Author
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Semaan M, Karam E, Baron C, and Pithioux M
- Subjects
- Adolescent, Aged, 80 and over, Child, Humans, Cortical Bone physiology, Elastic Modulus, Physiology methods
- Abstract
Purpose : Non-pathological child cortical bone (NPCCB) studies can provide clinicians with vital information and insights. However, assessing the anisotropic elastic properties of NPCCB remains a challenge for the biomechanical engineering community. For the first time, this paper provides elastic moduli values for NPCCB specimens in two perpendicular directions (longitudinal and transverse) and for two different structural components of bone tissue (osteon and interstitial lamellae). Materials and Methods : Microindentation is one of the reference methods used to measure bone stiffness. Here, 8 adult femurs (mean age 82 ± 8.9 years), 3 child femurs (mean age 13.3 ± 2.1 years), and 16 child fibulae (mean age 10.2 ± 3.9 years) were used to assess the elastic moduli of adult and child bones by microindentation. Results : For adult specimens, the mean moduli measured in this study are 18.1 (2.6) GPa for osteons, 21.3 (2.3) GPa for interstitial lamellae, and 13.8 (1.7) GPa in the transverse direction. For child femur specimens, the mean modulus is 14.1 (0.8) GPa for osteons, lower than that for interstitial lamellae: 15.5 (1.5) GPa. The mean modulus is 11.8 (0.7) GPa in the transverse direction. Child fibula specimens show a higher elastic modulus for interstitial lamellae 15.8 (1.5) than for osteons 13.5 (1.6), with 10.2 (1) GPa in the transverse direction. Conclusion : For the first time, NPCCB elastic modulus values are provided in longitudinal and transverse directions at the microscale level.
- Published
- 2019
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29. Pulp capping materials modulate the balance between inflammation and regeneration.
- Author
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Giraud T, Jeanneau C, Rombouts C, Bakhtiar H, Laurent P, and About I
- Subjects
- Dental Pulp, Humans, Inflammation, Regeneration, Dental Pulp Capping, Pulp Capping and Pulpectomy Agents
- Abstract
The interrelations between inflammation and regeneration are of particular significance within the dental pulp tissue inextensible environment. Recent data have demonstrated the pulp capacity to respond to insults by initiating an inflammatory reaction and dentin pulp regeneration. Different study models have been developed in vitro and in vivo to investigate the initial steps of pulp inflammation and regeneration. These include endothelial cell interaction with inflammatory cells, stem cell interaction with pulp fibroblasts, migration chambers to study cell recruitment and entire human tooth culture model. Using these models, the pulp has been shown to possess an inherent anti-inflammatory potential and a high regeneration capacity in all teeth and at all ages. The same models were used to investigate the effects of tricalcium silicate-based pulp capping materials, which were found to modulate the pulp anti-inflammatory potential and regeneration capacity. Among these, resin-containing materials such as TheraCal
® shift the pulp response towards the inflammatory reaction while altering the regeneration process. On the opposite, resin-free materials such as Biodentine™ have an anti-inflammatory potential and induce the pulp regeneration capacity. This knowledge contradicts the new tendency of developing resin-based calcium silicate hybrid materials for direct pulp capping. Additionally, it would allow investigating the modulatory effects of newly released pulp capping materials on the balance between tissue inflammation and regeneration. It would also set the basis for developing future capping materials targeting these processes., (Copyright © 2018 The Academy of Dental Materials. Published by Elsevier Inc. All rights reserved.)- Published
- 2019
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30. Tricalcium Silicate Capping Materials Modulate Pulp Healing and Inflammatory Activity In Vitro.
- Author
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Giraud T, Jeanneau C, Bergmann M, Laurent P, and About I
- Subjects
- Cell Adhesion drug effects, Cell Movement drug effects, Cell Proliferation drug effects, Cells, Cultured, Cytokines metabolism, Fibroblast Growth Factor 2 metabolism, Fibroblasts pathology, Humans, Inflammation Mediators metabolism, Interleukin-6 metabolism, Stimulation, Chemical, Transforming Growth Factor beta1 metabolism, Vascular Endothelial Growth Factor A metabolism, Calcium Compounds pharmacology, Dental Pulp cytology, Dental Pulp physiology, Fibroblasts metabolism, Fibroblasts physiology, Pulp Capping and Pulpectomy Agents pharmacology, Regeneration genetics, Silicates pharmacology, Wound Healing genetics, Wound Healing physiology
- Abstract
Introduction: On stimulation by lipoteichoic acid or by a physical injury, fibroblasts have been shown to play a major role in the initiation of the pulp inflammatory reaction and healing through secretion of complement proteins and growth factors. The application of direct pulp-capping materials on these cells may interfere with the inflammatory and the healing processes within the pulp's inextensible environment. This work was designed to study in vitro the effects of silicate-based materials on pulp fibroblast modulation of the initial steps of pulp inflammation and healing., Methods: The effects of Biodentine, TheraCal, and Xeno III eluates were studied on lipoteichoic acid-stimulated and physically injured fibroblasts. Cytokine secretion (interleukin 6, vascular endothelial growth factor, fibroblast growth factor-2, and transforming growth factor-β1) was quantified by enzyme-linked immunosorbent assay. Inflammatory THP-1 adhesion to endothelial cells and their migration and activation were studied in vitro. Human pulp fibroblast proliferation was investigated with the MTT test, and their migration to the injury site was studied with the scratch healing assay., Results: Interleukin 6 and vascular endothelial growth factor secretion increased with all materials but to a lesser extent with Biodentine. Fibroblast growth factor-2 and transforming growth factor-β1 secretion was significantly higher with Biodentine than with all other materials. THP-1 cell adhesion to endothelial cells and their activation were reduced by Biodentine and TheraCal. However, their migration decreased only with Biodentine. Fibroblast proliferation significantly increased with Biodentine but significantly decreased with Xeno III after day 6. Finally, only Biodentine induced fibroblast migration to the injury site in the scratch assay., Conclusions: These results confirm that pulp-capping materials affect the early steps of pulp inflammation and healing. They show that Biodentine had the highest pulp healing and anti-inflammatory potential when compared with the resin-containing materials. This highlights the interest of the material choice for direct pulp-capping., (Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)
- Published
- 2018
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31. Granulocyte-colony stimulating factor enhances bone fracture healing.
- Author
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Moukoko D, Pourquier D, Genovesio C, Thezenas S, Chabrand P, Roffino S, and Pithioux M
- Subjects
- Animals, Bone Nails, Bony Callus physiology, Femoral Fractures physiopathology, Femoral Fractures surgery, Fracture Fixation, Intramedullary, Fracture Healing physiology, Humans, Male, Osteotomy, Rats, Rats, Sprague-Dawley, Fracture Healing drug effects, Granulocyte Colony-Stimulating Factor administration & dosage
- Abstract
Background: Circulating mesenchymal stem cells contribute to bone repair. Their incorporation in fracture callus is correlated to their bioavailability. In addition, Granulocyte-colony stimulating factor induces the release of vascular and mesenchymal progenitors. We hypothesized that this glycoprotein stimulates fracture healing, and analyzed the effects of its administration at low doses on bone healing., Methods: 27 adult male Sprague-Dawley rats underwent mid-femur osteotomy stabilized by centromedullar pinning. In a post (pre) operative group, rats were subcutaneously injected with 5 μg/kg per day of Granulocyte-colony stimulating factor for 5 days after (before) surgery. In a control group, rats were injected with saline solution for 5 days immediately after surgery. A radiographic consolidation score was calculated. At day 35, femurs were studied histologically and underwent biomechanical tests., Findings: 5 weeks after surgery, mean radiographic scores were significantly higher in the Preop group 7.75 (SD 0.42) and in the Postop group 7.67 (SD 0.52) than in the control group 6.75 (SD 0.69). Biomechanical tests showed femur stiffness to be more than three times higher in both the Preop 109.24 N/mm (SD 51.86) and Postop groups 100.05 N/mm (SD 60.24) than in control 32.01 N/mm (SD 15.78). Mean maximal failure force was twice as high in the Preop group 68.66 N (SD 27.78) as in the control group 34.21 N (SD 11.79). Histological results indicated a later consolidation process in control than in treated groups., Interpretation: Granulocyte-colony stimulating factor injections strongly stimulated early femur fracture healing, indicating its potential utility in human clinical situations such as programmed osteotomy and fracture., (Copyright © 2018. Published by Elsevier Ltd.)
- Published
- 2018
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32. Light-cured Tricalcium Silicate Toxicity to the Dental Pulp.
- Author
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Jeanneau C, Laurent P, Rombouts C, Giraud T, and About I
- Subjects
- Aluminum Compounds pharmacology, Calcium Compounds pharmacology, Cells, Cultured, Dental Cements pharmacology, Dental Pulp Capping, Drug Combinations, Humans, Oxides pharmacology, Silicates pharmacology, Calcium Compounds toxicity, Curing Lights, Dental, Dental Pulp cytology, Dental Pulp drug effects, Silicates toxicity
- Abstract
Introduction: Numerous studies reported dentin bridge formation after pulp capping with tricalcium silicates. By contrast, pulp capping with resins leads to pulp toxicity and inflammation. Hybrid materials made up of tricalcium silicates and resins have also been developed to be used in direct pulp capping. This work was designed to study the consequences of adding resins to tricalcium silicates by investigating TheraCal (BISCO, Lançon De Provence, France) and Biodentine (Septodont, Saint Maur des Fosses, France) interactions with the dental pulp., Methods: Media conditioned with the biomaterials were used to analyze pulp fibroblast proliferation using the MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) test and proinflammatory cytokine interleukin 8 (IL-8) secretion using the enzyme-linked immunosorbent assay. The effects of conditioned media on dentin sialoprotein (DSP) and nestin expression by dental pulp stem cells (DPSCs) were investigated by immunofluorescence. The materials' interactions with the vital pulp were investigated using the entire tooth culture model., Results: TheraCal-conditioned media significantly decreased pulp fibroblast proliferation, whereas no effect was observed with Biodentine. When DPSCs were cultured with Biodentine-conditioned media, immunofluorescence showed an increased expression of DSP and nestin. This expression was lower with TheraCal, which significantly induced proinflammatory IL-8 release both in cultured fibroblasts and entire tooth cultures. This IL-8 secretion increase was not observed with Biodentine. Entire tooth culture histology showed a higher mineralization with Biodentine, whereas significant tissue disorganization was observed with TheraCal., Conclusions: Within the limits of these preclinical results, resin-containing TheraCal cannot be recommended for direct pulp capping., (Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
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33. Correlative Analysis of Vertebral Trabecular Bone Microarchitecture and Mechanical Properties: A Combined Ultra-high Field (7 Tesla) MRI and Biomechanical Investigation.
- Author
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Guenoun D, Fouré A, Pithioux M, Guis S, Le Corroller T, Mattei JP, Pauly V, Guye M, Bernard M, Chabrand P, Champsaur P, and Bendahan D
- Subjects
- Aged, Aged, 80 and over, Biomechanical Phenomena physiology, Bone Density physiology, Cadaver, Female, Humans, Lumbar Vertebrae pathology, Lumbar Vertebrae physiology, Male, Regression Analysis, Reproducibility of Results, Absorptiometry, Photon methods, Cancellous Bone diagnostic imaging, Lumbar Vertebrae diagnostic imaging, Magnetic Resonance Imaging methods, Stress, Mechanical
- Abstract
Study Design: High-resolution imaging and biomechanical investigation of ex-vivo vertebrae., Objective: The aim of this study was to assess bone microarchitecture of cadaveric vertebrae using ultra-high field (UHF) 7 Tesla magnetic resonance imaging (MRI) and to determine whether the corresponding microarchitecture parameters were related to bone mineral density (BMD) and bone strength assessed by dual-energy x-ray absorptiometry (DXA) and mechanical compression tests., Summary of Background Data: Limitations of DXA for the assessment of bone fragility and osteoporosis have been recognized and criteria of microarchitecture alteration have been included in the definition of osteoporosis. Although vertebral fracture is the most common osteoporotic fracture, no study has assessed directly vertebral trabecular bone microarchitecture., Methods: BMD of 24 vertebrae (L2, L3, L4) from eight cadavers was investigated using DXA. The bone volume fraction (BVF), trabecular thickness (Tb.Th), and trabecular spacing (Tb.Sp) of each vertebra were quantified using UHF MRI. Measurements were performed by two operators to characterize the inter-rater reliability. The whole set of specimens underwent mechanical compression tests to failure and the corresponding failure stress was calculated., Results: The inter-rater reliability for bone microarchitecture parameters was good with intraclass correlation coefficients ranging from 0.82 to 0.94. Failure load and stress were significantly correlated with BVF, Tb.Sp, and BMD (P < 0.05). Tb.Th was only correlated with the failure stress (P < 0.05). Multiple regression analysis demonstrated that the combination of BVF and BMD improved the prediction of the failure stress from an adjusted R = 0.384 for BMD alone to an adjusted R = 0.414., Conclusion: We demonstrated for the first time that the vertebral bone microarchitecture assessed with UHF MRI was significantly correlated with biomechanical parameters. Our data suggest that the multimodal assessment of BMD and trabecular bone microarchitecture with UHF MRI provides additional information on the risk of vertebral bone fracture and might be of interest for the future investigation of selected osteoporotic patients., Level of Evidence: N /A.
- Published
- 2017
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34. Bone substitutes in adolescent idiopathic scoliosis surgery using sublaminar bands: is it useful? A case-control study.
- Author
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Pesenti S, Ghailane S, Varghese JJ, Ollivier M, Peltier E, Choufani E, Bollini G, Blondel B, and Jouve JL
- Subjects
- Adolescent, Bone Substitutes adverse effects, Bone Transplantation adverse effects, Case-Control Studies, Child, Equipment Failure, Female, Follow-Up Studies, Humans, Male, Prospective Studies, Pseudarthrosis epidemiology, Pseudarthrosis etiology, Retrospective Studies, Spinal Fusion adverse effects, Spinal Fusion methods, Transplantation, Autologous, Treatment Outcome, Young Adult, Bone Substitutes therapeutic use, Bone Transplantation methods, Scoliosis surgery, Spinal Fusion statistics & numerical data
- Abstract
Introduction: In order to avoid pseudarthrosis in adolescent idiopathic (AIS) patients, it is recommended to bring additional bone graft or substitute. Modern rigid instrumentations have been shown to provide less pseudarthroses even without bone substitutes. The aim of our study was to determine the impact of using bones substitutes on fusion rates in adolescent idiopathic scoliosis patients undergoing PSF with sublaminar bands., Method: AIS patients scheduled to undergo PSF with sublaminar bands were prospectively enrolled into this study and not given any bone substitutes (no-substitute group). Data were collected and analyzed in patients with at least two years of follow-up. Pseudarthrosis was diagnosed if at least one of the following was present: persistent back pain, hardware failure, loss of correction greater than 10°. The results were compared to a control group who received bone substitutes for the same surgical procedure., Results: Eighty-eight patients were included. For the whole cohort, the mean age was 14.8 years old and the mean follow-up was 30.9 months. For the 'no-substitute' group (n = 44), the mean Cobb angle was 56° pre-operatively, 20.1° post-operatively, and 22° at final follow-up. The fusion rate was not statistically different between the two groups (97.7% vs 95.5%, p = 0.56). At last follow-up, one pseudarthrosis occurred in the 'no substitute' group and two in the control group., Discussion: This is the first study to determine the impact of bone substitutes in AIS fusion using sublaminar bands. In our study, the use of local autologous bone graft alone resulted in a fusion rate of 97.7% despite the use of more flexible instrumentation. The high rate of fusion in AIS patients is more probably due to the healing potential of these young patients rather than to the type of instrumentation., Conclusion: The use of additional bone graft or bone substitutes may not be mandatory when managing AIS., Level of Evidence: 4.
- Published
- 2017
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35. Potential Therapeutic Strategy of Targeting Pulp Fibroblasts in Dentin-Pulp Regeneration.
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Jeanneau C, Lundy FT, El Karim IA, and About I
- Subjects
- Complement Membrane Attack Complex, Complement System Proteins physiology, Humans, Dental Pulp physiology, Dentin physiology, Fibroblasts physiology, Regeneration
- Abstract
Fibroblasts represent the most abundant population within the dental pulp. Although other cell types such as odontoblasts and stem cells have been extensively investigated, very little attention was given to the fibroblasts, which have major roles in regulating the pulp biology and function under normal and pathologic conditions. Indeed, although pulp fibroblasts control the pulp vascularization and innervation under physiological conditions, these cells synthesize growth factors that enhance dentin-pulp regeneration, vascularization, and innervation. Pulp fibroblasts also represent a unique cell population because they are the only non-hepatic and non-immune cell type capable of synthesizing all complement proteins leading to production of biologically active fragments such as C3a, C5a, and membrane attack complex, which play major roles in the pulp regeneration processes. C3a fragment is involved in inducing the proliferation of both stem cells and pulp fibroblasts. It is also involved in stem cell mobilization and pulp fibroblast recruitment. C5a guides nerve sprouting and stem cell recruitment. The membrane attack complex fixes on cariogenic bacteria walls, leading to their direct destruction. These data demonstrate the central role played by pulp fibroblasts in regulating the dentin-pulp tissue by directly destroying cariogenic bacteria and by releasing bioactive fragments involved in nerve sprouting and stem cell recruitment and pulp regeneration. Taken together, this shows that targeting pulp fibroblasts represents a realistic strategy to induce complete dentin-pulp regeneration., (Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.)
- Published
- 2017
- Full Text
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36. Active tuning of stroke-induced vibrations by tennis players.
- Author
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Chadefaux D, Rao G, Androuet P, Berton E, and Vigouroux L
- Subjects
- Biomechanical Phenomena, Elbow physiology, Electromyography, Equipment Design, Hand Strength physiology, Humans, Male, Man-Machine Systems, Wrist physiology, Young Adult, Forearm physiology, Sports Equipment, Tennis physiology, Vibration
- Abstract
This paper investigates how tennis players control stroke-induced vibration. Its aim is to characterise how a tennis player deals with entering vibration waves or how he/she has the ability to finely adjust them. A specific experimental procedure was designed, based on simultaneously collecting sets of kinematic, vibration and electromyographic data during forehand strokes using various commercial rackets and stroke intensities. Using 14 expert players, a wide range of excitations at spectral and temporal levels were investigated. Energetic and spectral descriptors of stroke-induced vibration occurring at the racket handle and at the player's wrist and elbow were computed. Results indicated that vibrational characteristics are strongly governed by grip force and to a lower extent by the racket properties. Grip force management drives the amount of energy, as well as its distribution, into the forearm. Furthermore, hand-grip can be assimilated to an adaptive filter which can significantly modify the spectral parameters propagating into the player's upper limb. A significant outcome is that these spectral characteristics are as much dependent on the player as on the racket. This contribution opens up new perspectives in equipment manufacture by underlining the need to account for player/racket interaction in the design process.
- Published
- 2017
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37. The effects of player grip on the dynamic behaviour of a tennis racket.
- Author
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Chadefaux D, Rao G, Le Carrou JL, Berton E, and Vigouroux L
- Subjects
- Biomechanical Phenomena, Equipment Design, Humans, Hand Strength, Sports Equipment, Tennis physiology
- Abstract
The aim of this article is to characterise the extent to which the dynamic behaviour of a tennis racket is dependent on its mechanical characteristics and the modulation of the player's grip force. This problem is addressed through steps involving both experiment and modelling. The first step was a free boundary condition modal analysis on five commercial rackets. Operational modal analyses were carried out under "slight", "medium" and "strong" grip force conditions. Modal frequencies and damping factors were then obtained using a high-resolution method. Results indicated that the dynamic behaviour of a racket is not only determined by its mechanical characteristics, but is also highly dependent on the player's grip force. Depending on the grip force intensity, the first two bending modes and the first torsional mode frequencies respectively decreased and increased while damping factors increased. The second step considered the design of a phenomenological hand-gripped racket model. This model is fruitful in that it easily predicts the potential variations in a racket's dynamic behaviour according to the player's grip force. These results provide a new perspective on the player/racket interaction optimisation by revealing how grip force can drive racket dynamic behaviour, and hence underlining the necessity of taking the player into account in the racket design process.
- Published
- 2017
- Full Text
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38. Use of porous tantalum components in Paprosky two and three acetabular revision. A minimum five-year follow-up of fifty one hips.
- Author
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Flecher X, Appy B, Parratte S, Ollivier M, and Argenson JN
- Subjects
- Adult, Aged, Aged, 80 and over, Arthroplasty, Replacement, Hip methods, Biocompatible Materials, Bone Resorption etiology, Female, Follow-Up Studies, Humans, Male, Middle Aged, Prosthesis Failure, Reoperation, Retrospective Studies, Tantalum, Acetabulum surgery, Arthroplasty, Replacement, Hip instrumentation, Bone Resorption surgery, Hip Joint surgery, Hip Prosthesis
- Abstract
Introduction: Recent studies have reported short-term favourable results of tantalum-made components in acetabular revisions with bone loss. However, there is a lack of information regarding the mid to long-term results of such components., Objectives: The objective of this study was to analyse the outcome and survivorship of acetabular revision hip arthroplasty using tantalum components for loosening associated with bone loss at a minimum of five-year follow-up., Methods: We retrospectively reviewed 51 consecutive patients (51 hips) who had an acetabular revision using porous tantalum components at a minimum follow-up of five years. The mean age was 64 years (range, 31-87). There were 27 males and 24 females, 47 right hips and four left hips. Twenty-five (49 %) included a femoral revision. According to Paprosky's classification 18 hips were classified type 2A, 11 type 2B, ten type 2C, seven type 3A and five type 3B. No bone grafting was performed. Sixteen hips (31.3 %) required the use of additional tantalum-made augments stabilized by screws and cement at the cup-augment interface., Results: At a mean followup of 6.8 years (range, 5.1-10 years), the Harris hip score improved from 44 pre- operatively (range, 23-72) to 84 post-operatively (range, 33-98). The mean post-operative hip centre position in relation to the teardrop was 29 mm (range, 20-43 mm) horizontally and 21 mm (range, 8-36 mm) vertically. The mean acetabular inclination was 42° (range, 17-60°). Six hips (11.7 %) required a re-operation without component revision (two for chronic instability, one ossification removal, one haematoma, one deep infection and one periprosthetic femoral fracture). One patient required a cup re-revision for septic loosening. No aseptic loosening occurred. At last followup the radiological analysis showed one evolutive osteolysis and one screw breakage. The global survivorship was 92.3 % at 64 months. If only aseptic loosening was defined as the end-point the survivorship was 100 % at 64 months., Conclusions: When facing an acetabular revision with severe bone loss, tantalum-made components can provide a stable fixation. This study at a minimum five-year follow-up compares favourably with other reconstruction techniques, but longer follow-up is still required.
- Published
- 2017
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39. Pulp Vascularization during Tooth Development, Regeneration, and Therapy.
- Author
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Rombouts C, Giraud T, Jeanneau C, and About I
- Subjects
- Animals, Bone Regeneration physiology, Dental Pulp blood supply, Humans, Neovascularization, Physiologic physiology, Tissue Engineering methods, Tooth blood supply, Dental Pulp growth & development, Tooth growth & development
- Abstract
The pulp is a highly vascularized tissue situated in an inextensible environment surrounded by rigid dentin walls, with the apical foramina being the only access. The pulp vascular system is not only responsible for nutrient supply and waste removal but also contributes actively to the pulp inflammatory response and subsequent regeneration. This review discusses the underlying mechanisms of pulp vascularization during tooth development, regeneration, and therapeutic procedures, such as tissue engineering and tooth transplantation. Whereas the pulp vascular system is established by vasculogenesis during embryonic development, sprouting angiogenesis is the predominant process during regeneration and therapeutic processes. Hypoxia can be considered a common driving force. Dental pulp cells under hypoxic stress release proangiogenic factors, with vascular endothelial growth factor being one of the most potent. The benefit of exogenous vascular endothelial growth factor application in tissue engineering has been well demonstrated. Interestingly, dental pulp stem cells have an important role in pulp revascularization. Indeed, recent studies show that dental pulp stem cell secretome possesses angiogenic potential that actively contributes to the angiogenic process by guiding endothelial cells and even by differentiating themselves into the endothelial lineage. Although considerable insight has been obtained in the processes underlying pulp vascularization, many questions remain relating to the signaling pathways, timing, and influence of various stress conditions.
- Published
- 2017
- Full Text
- View/download PDF
40. Minimalistic optic flow sensors applied to indoor and outdoor visual guidance and odometry on a car-like robot.
- Author
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Mafrica S, Servel A, and Ruffier F
- Subjects
- Animals, Automobile Driving, Calibration, Humans, Insecta physiology, Pattern Recognition, Visual, Software, Algorithms, Automobiles, Optic Flow, Robotics instrumentation
- Abstract
Here we present a novel bio-inspired optic flow (OF) sensor and its application to visual guidance and odometry on a low-cost car-like robot called BioCarBot. The minimalistic OF sensor was robust to high-dynamic-range lighting conditions and to various visual patterns encountered thanks to its M
2 APIX auto-adaptive pixels and the new cross-correlation OF algorithm implemented. The low-cost car-like robot estimated its velocity and steering angle, and therefore its position and orientation, via an extended Kalman filter (EKF) using only two downward-facing OF sensors and the Ackerman steering model. Indoor and outdoor experiments were carried out in which the robot was driven in the closed-loop mode based on the velocity and steering angle estimates. The experimental results obtained show that our novel OF sensor can deliver high-frequency measurements ([Formula: see text]) in a wide OF range (1.5-[Formula: see text]) and in a 7-decade high-dynamic light level range. The OF resolution was constant and could be adjusted as required (up to [Formula: see text]), and the OF precision obtained was relatively high (standard deviation of [Formula: see text] with an average OF of [Formula: see text], under the most demanding lighting conditions). An EKF-based algorithm gave the robot's position and orientation with a relatively high accuracy (maximum errors outdoors at a very low light level: [Formula: see text] and [Formula: see text] over about [Formula: see text] and [Formula: see text]) despite the low-resolution control systems of the steering servo and the DC motor, as well as a simplified model identification and calibration. Finally, the minimalistic OF-based odometry results were compared to those obtained using measurements based on an inertial measurement unit (IMU) and a motor's speed sensor.- Published
- 2016
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41. In silico CDM model sheds light on force transmission in cell from focal adhesions to nucleus.
- Author
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Milan JL, Manifacier I, Beussman KM, Han SJ, Sniadecki NJ, About I, and Chabrand P
- Subjects
- Cell Adhesion, Cells, Cultured, Computer Simulation, Endothelial Cells physiology, Endothelial Cells ultrastructure, Extracellular Matrix physiology, Humans, Models, Biological, Cell Nucleus physiology, Cytoskeleton physiology, Focal Adhesions physiology, Mechanotransduction, Cellular physiology
- Abstract
Cell adhesion is crucial for many types of cell, conditioning differentiation, proliferation, and protein synthesis. As a mechanical process, cell adhesion involves forces exerted by the cytoskeleton and transmitted by focal adhesions to extracellular matrix. These forces constitute signals that infer specific biological responses. Therefore, analyzing mechanotransduction during cell adhesion could lead to a better understanding of the mechanobiology of adherent cells. For instance this may explain how, the shape of adherent stem cells influences their differentiation or how the stiffness of the extracellular matrix affects adhesion strength. To assess the mechanical signals involved in cell adhesion, we computed intracellular forces using the Cytoskeleton Divided Medium model in endothelial cells adherent on micropost arrays of different stiffnesses. For each cell, focal adhesion location and forces measured by micropost deflection were used as an input for the model. The cytoskeleton and the nucleoskeleton were computed as systems of multiple tensile and compressive interactions. At the end of computation, the systems respected mechanical equilibrium while exerting the exact same traction force intensities on focal adhesions as the observed cell. The results indicate that not only the level of adhesion forces, but also the shape of the cell has an influence on intracellular tension and on nucleus strain. The combination of experimental micropost technology with the present CDM model constitutes a tool able to estimate the intracellular forces., (Copyright © 2016. Published by Elsevier Ltd.)
- Published
- 2016
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42. Psycho-Physiological Responses of Obese Adolescents to an Intermittent Run Test Compared with a 20-M Shuttle Run.
- Author
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Rey O, Maïano C, Nicol C, Mercier CS, and Vallier JM
- Abstract
Among the running field tests that measure aerobic fitness indirectly, the 20-m shuttle run test is the one most commonly used among obese youth. However, this back and forth running test induces premature cessation of exercise in this population. The present study aimed to examine the psycho-physiological responses of obese adolescents to an intermittent (15-15) progressive and maximal run test as compared with a continuous shuttle run test. Eleven obese adolescents (age: 14-15 years; BMI = 34.01 ± 5.30 kg·m
-2 ) performed both tests. A two-way ANOVA examined the main effects of the running test, participant's sex, and their interaction on maximal aerobic performance (net exercise duration and final velocity), physiological values (heart rate, pulmonary oxygen uptake, respiratory exchange ratio and blood lactate concentration) and psychological responses (rating of perceived exertion, and physical self-perceptions). Oxygen uptake and heart-rate values at 9 km·h-1 were also compared. Compared with a 20-m shuttle run, the 15-15 test induced lower pulmonary oxygen uptake values at 9 km/h (28.3 ± 2.7 vs. 35.4 ± 2.7 ml·min-1 ·kg-1 ) and finished with higher maximal velocity and net exercise duration (566 ± 156 vs. 346 ± 156 s, p < 0.001), with no inter-test physiological difference. The 15-15 test also resulted in higher ratings of perceived exertion (16.0 ± 1.2 vs. 12.7 ± 1.6, p < 0.001) and improved perceived physical condition compared with the 20-m shuttle run (+1.4 ± 1.4 vs. +0.2 ± 1.0, p < 0.05). Both tests induced a maximal aerobic power of obese adolescents, but the 15-15 test provided a more progressive speed increment and longer exercise duration. The 15-15 test also elicited a significant improvement of perceived physical condition. In conclusion the 15-15 test can be considered a relevant field test for assessing the aerobic fitness of obese adolescents.- Published
- 2016
43. The Influence of the 'Trier Social Stress Test' on Free Throw Performance in Basketball: An Interdisciplinary Study.
- Author
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Mascret N, Ibáñez-Gijón J, Bréjard V, Buekers M, Casanova R, Marqueste T, Montagne G, Rao G, Roux Y, and Cury F
- Subjects
- Adolescent, Adult, Cross-Over Studies, Exercise Test, Humans, Male, Multivariate Analysis, Saliva chemistry, Basketball psychology, Hydrocortisone metabolism, Psychomotor Performance physiology, Stress, Psychological metabolism
- Abstract
The aim of the present study was to explore the relationship between stress and sport performance in a controlled setting. The experimental protocol used to induce stress in a basketball free throw was the Trier Social Stress Test (TSST) and its control condition (Placebo-TSST). Participants (n = 19), novice basketball players but trained sportspersons, were exposed to two counterbalanced conditions in a crossover design. They were equipped with sensors to measure movement execution, while salivary cortisol and psychological state were also measured. The task consisted of two sequences of 40 free throws, one before either the TSST or Placebo-TSST and one after. Physiological and psychological measures evidenced that the TSST induced significant stress responses, whereas the Placebo-TSST did not. Shooting performance remained stable after the TSST but decreased after the Placebo-TSST. We found no effect of the TSST or Placebo-TSST on movement execution. A multivariate model of free throw performance demonstrated that timing, smoothness and explosiveness of the movements are more relevant to account for beginner's behavior than stress-related physiological and psychological states. We conclude that the TSST is a suitable protocol to induce stress responses in sport context, even though the effects on beginners' free throw performance and execution are small and complex.
- Published
- 2016
- Full Text
- View/download PDF
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