Download or read book CONTRIBUTION A L ETUDE DE LA CORROSION ET DE LA RELATION EPITHELIO IMPLANTAIRE DES IMPLANTS ENDO OSSEUX EN TITANE written by YVES.. KERORGANT and published by . This book was released on 1987 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Contribution l tude de la corrosion galvanique entre un implant dentaire base titane et sa suprastructrure written by Brigitte Grosgogeat-Balayre and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Corrosion and Degradation of Implant Materials written by B. C. Syrett and published by ASTM International. This book was released on 1979 with total page 358 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Bio Tribocorrosion in Biomaterials and Medical Implants written by Yu Yan and published by Elsevier. This book was released on 2013-09-30 with total page 434 pages. Available in PDF, EPUB and Kindle. Book excerpt: During their service life, most biomaterials and medical implants are vulnerable to tribological damage. In addition, the environments in which they are placed are often corrosive. The combination of triobology, corrosion and the biological environment has been named ‘bio-tribocorrosion’. Understanding this complex phenomenon is critical to improving the design and service life of medical implants. This important book reviews recent key research in this area. After an introduction to the topography of bio-tribocorrosion, Part one discusses different types of tribocorrosion including fatigue-corrosion, fretting-corrosion, wear-corrosion and abrasion-corrosion. The book also discusses the prediction of wear in medical devices. Part two looks at biological effects on tribocorrosion processes, including how proteins interact with material surfaces and the evolution of surface changes due to bio-tribocorrosion resulting from biofilms and passive films. Part three reviews the issue of bio-tribocorrosion in clinical practice, including dental applications and joint replacement as well the use of coatings and test methods for bio-tribocorrosion. With its international team of contributors, Bio-tribocorrosion in biomaterials and medical implants is a standard reference for those researching and developing medical devices as well as clinicians in such areas as dentistry and orthopaedic surgery. Reviews recent research in bio-tribocorrosion and its role in improving the design and service life of medical implants Discusses types of bio-tribocorrosion including fatigue and wear corrosion Examines biological effects on bio-tribocorrosion processes including interaction of proteins with metal surfaces

Download or read book CONTRIBUTION A L ETUDE DES IMPLANTS DENTAIRES ENDO OSSEUX written by VERONIQUE.. CANTIN and published by . This book was released on 1986 with total page 298 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book CONTRIBUTION A L ETUDE CRITIQUE DES IMPLANTS ENDO OSSEUX written by GILLES.. JOLLY and published by . This book was released on 1986 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book IMPLANT ENDO OSSEUX written by MARIE-NOELLE.. CHEVALIER and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book CONTRIBUTION A L ETUDE DES DIFFERENTS SYSTEMES IMPLANTAIRES written by JEAN-LUC.. BERGERO and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book CONTRIBUTION A L ETUDE DU POSITIONNEMENT OPTIMAL D UN IMPLANT ENDO OSSEUX written by EIRIK.. PERTUS and published by . This book was released on 1993 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effect of Different Implant abutment Connection Geometry and Abutment Alloy on Corrosion Product Release and Cell Response written by Ghada O. Alrabeah and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Problem: The observed positive effect of the platform-switching concept on peri- implant bone level is not well understood. Dental implants may be prone to tribocorrosion leading to the release of metal ions and particles which may disrupt bone homeostasis Objectives: The aim of this project was to compare the amount of corrosion products released from different implant-abutment couplings with different connection geometries under accelerated corrosion tests, and to evaluate different osteoblastic cell responses to the released products. Materials and methods: Part I: Titanium cylinders were connected to titanium alloy (Ti-6Al-4V) and cobalt"†chrome alloy abutments forming either platform-switched or platform-matched groups. Samples were subjected to static immersion in 1% lactic acid for 1 week. Metal ions released were measured and microscopic analyses were performed pre- and post- immersion to assess corrosion at the interface. Part II: Osteoblasts were treated with culture media containing different concentrations of metal ions obtained from the results of part I. Osteoblasts treated with ion-free culture medium served as the controls. Osteoblastic viability, apoptosis and expression of genes related to bone resorption were analysed. Part III: The samples used in part I were incubated with osteoblasts. Viability, apoptosis and expression of the genes tested in part II were investigated. Part IV: Titanium implants were coupled with either titanium, gold, cobalt-chrome, or zirconia abutments forming either platform-switched or platform-matched groups. The specimens were subjected to cyclic loading under wet acidic environment. Metal ions released were measured and microscopic evaluations were performed pre- and post- immersion for tribocorrosion assessment and wear particle characterization. Results: Part I: The implant"â€abutment couplings underwent an active corrosion process resulting in metal ions released into the surrounding environment. The platform- matched groups demonstrated higher amount of metal ion release. Part II and Part III: Osteoblastic cell viability, apoptosis, and regulation of bone resorbing mediators were significantly altered in the presence of both the metal ions and the different implant-abutment couplings. The observed changes in some of the biological responses tested were more pronounced in groups representing the platform-matched implant-abutment couplings. Part IV: The implant"â€abutment couplings underwent an active tribocorrosion processes resulting in metal ions and wear particles released into the surrounding environment. The platform-matched groups demonstrated higher amount of metal ion release and more surface damage Conclusion: Platform-switching concept had a positive effect in reducing metal ion release and wear features from dental implants which in turn minimised the adverse osteoblastic biologic responses related to peri-implant bone loss, therefore highlighting the possible role of corrosion products in the mediation of crestal bone loss around dental implants.

Download or read book Contribution l tude du comportement biom canique de l environnement d un implant dentaire written by Marwan Daas and published by . This book was released on 2008 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plusieurs questions se posent encore, d’un point de vue scientifique, sur la nature du comportement immédiat et l’évolution de l’interface os-implant lorsqu’un implant est mis en charge sous une prothèse dentaire fixée ou amovible. Les objectifs de notre travail étaient donc d’étudier la possibilité d’une mise en charge immédiate des implants dentaires, le remodelage osseux péri-implantaire permettant d’assurer l’ostéointégration ainsi que l’influence des paramètres prothétiques d’une prothèse amovible complète supra-implantaire (PACSI) mandibulaire sur l’implant et son environnement. Deux modèles numériques ont été conçus. Le premier modèle concernait le maxillaire avec l’utilisation d’un pilier implantaire angulé placé sur un implant au niveau d’une incisive latérale. Il nous a permis d’étudier le remodelage osseux autour d’un implant sur une période d’ostéointégration donnée de 26 mois. Un concept de chargement de sécurité, correspondant à la préservation de l’intégrité osseuse, a été introduit afin de quantifier l’effort maximal pouvant être appliqué à l’implant entre sa première mise en charge et son état ostéointégré. Un modèle mandibulaire, avec la mise en place des attachements boules sur deux implants dans la région symphysaire et une PACSI, nous a permis de montrer qu’une grande part de l’effort de mastication transitait par la muqueuse. Les calculs ont également montré que la position des implants au niveau des canines répond au mieux aux objectifs recherchés en PACSI, c'est-à-dire une meilleure prise en charge de l’effort de mastication par les surfaces d’appuis ostéo-muqueuses et des contraintes transmises à l’os péri-implantaire moins importantes.

Download or read book CONTRIBUTION A L ETUDE DES IMPLANTS written by VERONIQUE.. BAUDEQUIN and published by . This book was released on 1987 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Biocorrosion and Aseptic Loosening of Metal Implants written by Dieter Cadosch and published by . This book was released on 2011 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal orthopaedic devices exposed to a physiological environment remain prone to corrosion by several mechanisms, leading to the production of significant amounts of non-biocompatible wear particles and metal ions. Beside the well-known mechanical wear and electrochemical redox reactions, metal implants undergo corrosion through biological activities. The results presented in this thesis suggest that mature osteoclasts are able to enhance corrosion of titanium and stainless steel implants and contribute to the release of relevant amounts of corresponding metal ions into the peri-implant tissues and the systemic blood circulation. In addition to the increased osteolytic activity caused by wear particles, the results detailed in this thesis strongly suggests that released titanium ions in the 4+ oxidation state (Ti(IV)) contribute to the pathophysiological mechanism of aseptic loosening by stimulating both the bone metabolism and immune system through a series of direct and indirect pathways. Aseptic loosening is believed to be caused by an increased osteolytic activity at the bone-implant interface leading to loss of stability and ultimately implant failure. Titanium (IV) ions are able to directly induce the differentiation of osteoclast precursors toward mature and functional osteoclasts in ~20% of individuals. Additionally, Ti(IV) ions stimulate the secretion of pro-inflammatory cytokines that are known to enhance osteoclast recruitment, differentiation, activation and survival. More evidence is linking the immune system to the bone and to its involvement in the pathophysiology of aseptic loosening. Titanium (IV) ions influence phenotype and function of T-lymphocytes, resulting in activation of a CD69+ and CCR4+ Tlymphocyte and secretion of receptor activator of NF-mB ligand (RANK-L). To date, revision surgery remains the only option for the treatment of a failed orthopaedic implant caused by aseptic loosening. These results represent an important step towards a better understanding of the complex pathophysiological mechanism of aseptic loosening in patients with titanium implants, and may open new research perspectives in this field which could offer innovative therapeutic options and reduce the rate of aseptic loosening.

Download or read book Bio tribocorrosion in biomaterials and medical implants written by R.J.K. Wood and published by Elsevier Inc. Chapters. This book was released on 2013-09-30 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: The tribological performance of implant materials within the body where the pH can vary between 7.4 and 4.0, depending on whether the joint is infected or not, is extremely harsh and varies significantly from that experienced in other engineering environments. Three wear mechanisms that affect biomedical and, in particular, orthopaedic implants are regularly reported. These are adhesion, abrasion and fatigue. The wear mechanisms in biomedical implants, particularly hip joints, are reported to be a function of the following variables: type of materials used, contact stresses, lubricants and clearance, surface hardness and roughness, type of articulation due to motion, number of cycles, solution particle count and distribution, and tribocorrosion.

Download or read book Solutions mat riaux et g om triques pour la r alisation de dispositifs m dicaux implantables sur mesure en alliages de titane written by Paul Didier and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: L'utilisation des Dispositifs Médicaux Implantables (DMI) en alliage de titane, principalement en Ti-6Al-4V, s'est fortement développée ces dernières décennies. D'un point de vue biologique et chimique, certains éléments de cet alliage tels que le vanadium et l'aluminium sont considérés comme potentiellement toxiques. D'un point de vue des propriétés mécaniques, le Ti-6Al-4V est significativement plus rigide que l'os cortical sur lequel les prothèses/implants sont fixés. Cette différence de rigidité entre l'os et l'implant est à l'origine d'une déviation des contraintes (appelée « stress-shielding ») qui peut finalement aboutir au descellement du dispositif dû à des pertes osseuses. Le travail de cette thèse a pour objectif d'apporter des solutions tant sur le choix du matériau que sur le choix de la géométrie des DMI, pouvant permettre l'amélioration du transfert de charge à l'interface. Le domaine dentaire où les efforts mis en jeu sont importants constitue un environnement adéquat à la mise en œuvre de ces solutions matériaux et géométriques. Deux types de dispositifs sont ainsi envisagés dans cette étude : les implants endo-osseux et les implants supra-osseux à plaque d'ostéosynthèse. Le positionnement des implants classiques, dits endo-osseux, est évalué au regard de l'os péri-implanté par une étude numérique multiparamétrique, prenant en compte des critères mécaniques. Les implants supra-osseux sont eux destinés à la réhabilitation d'arcades dentaires complètes de patients aux pathologies plus atypiques, notamment lorsque la pose d'implants endo-osseux n'est pas envisageable. La nécessité de disposer de formes individualisées aux patients justifie pleinement une réalisation par fabrication additive SLM (Selective Laser Melting). Cette approche nécessite cependant de s'intéresser à tous les aspects de la chaîne de valeurs de réalisation de DMI par fabrication additive métallique. Dans l'étape de dimensionnement il ne s'agit plus seulement de tenir compte de la tenue mécanique du dispositif implanté mais d'optimiser topologiquement sa géométrie au regard des sollicitations appliquées à l'os, afin d'optimiser le transfert de charge en l'os et l'implant. L'élaboration de ces dispositifs, sur-mesure, doit nécessairement tenir compte des opérations de parachèvement post-fabrication, par des procédés soustractifs. Ces étapes de fonctionnalisation constituent encore à ce jour un verrou qui limite l'utilisation de la fabrication additive. Les problématiques de reprise en usinage de pièces sur-mesure sont liées au transfert entre la machine de fabrication additive et le centre d'usinage. L'idée développée consiste à l'utilisation des supports de fabrication additive comme montage d'usinage sur-mesure. Pour anticiper les potentielles instabilités pendant cette opération de parachèvement, un outil numérique est développé, couplé à un modèle analytique de détermination des efforts de coupe en fraisage périphérique. Enfin, le contrôle de l'état de surface des DMI issus du procédé SLM par sablage et tribofinition, en lien avec une étude de biocompatibilité, est présenté.

Download or read book CONTRIBUTION A L ETUDE DE L EVOLUTION MORPHOLOGIQUE ET STRUCTURALE DES IMPLANTS ENDO OSSEUX written by ELIAS.. CHALHOUB and published by . This book was released on 1989 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book L tat de surface du titane et de ses alliages en implantologie written by Ayham Mousa and published by . This book was released on 2012 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Le succès de l'implant dentaire en titane est basé sur leur ostéointegration osseuse qui est conditionné par le contact entre l'os et la surface de l'implant. Les excellentes propriétés de surface confèrent au titane pur et à ses alliages une très bonne résistance à la corrosion, ainsi qu'une excellente biocompatibilité. Cependant, ces propriétés peuvent être modifiées en fonction du traitement de surface appliqué pendant le processus de fabrication de l'implant. Un nombre très important d'études a été réalisé afin d'améliorer les propriétés de surface du titane, ainsi, de nombreux procédés de traitement de surface ont été développés et appliqués sur la surfaces des implants dentaire, permettant d'améliorer leur ostéointégration. Dans ce travail, nous avons détaillé les différents procédés de traitement de surface utilisés par l'industrie implantaire. Souvent un ou plusieurs traitements sont appliqués afin d'obtenir l'état de surface souhaité. Nous avons donc souhaité comparer l'état de surface d'implants dentaires des marques différentes vendues en France.La comparaison de l'état de surface des implants commercialisés a permis de mettre en évidence des différences entre ces implants, et l'absence d'une norme indépendante reconnue pour les états de surface des implants dentaires. Nous avons aussi noté l'absence d'un contrôle de qualité indépendant vis-à-vis des fabricants. L'avenir de l'implantologie dentaire devrait viser à développer des surfaces avec une topographie et une composition chimique contrôlée et normalisée. Cette approche permettra de mieux comprendre les interactions entre les tissus et les cellules de l'organisme avec les surfaces d'implantaires.