976 resultados para Implant endo-osseux


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OBJECTIVES: The aim of this systematic review is to evaluate, analysing the dental literature, whether: * Patients on intravenous (IV) or oral bisphosphonates (BPs) can receive oral implant therapy and what could be the risk of developing bisphosphonate-related osteonecrosis of the jaw (BRONJ)? * Osseointegrated implants could be affected by BP therapy. MATERIAL AND METHODS: A Medline search was conducted and all publications fulfilling the inclusion and exclusion criteria from 1966 until December 2008 were included in the review. Moreover, the Cochrane Data Base of Systematic Reviews, and the Cochrane Central Register of Controlled Trials and EMBASE (from 1980 to December 2008) were searched for English-language articles published between 1966 and 2008. Literature search was completed by a hand research accessing the references cited in all identified publications. RESULTS: The literature search rendered only one prospective and three retrospective studies. The prospective controlled non-randomized clinical study followed patients with and without BP medication up to 36 months after implant therapy. The patients in the experimental group had been on oral BPs before implant therapy for periods ranging between 1 and 4 years. None of the patients developed BRONJ and implant outcome was not affected by the BP medication. The three selected retrospective studies (two case-controls and one case series) yielded very similar results. All have followed patients on oral BPs after implant therapy, with follow-up ranging between 2 and 4 years. BRONJ was never reported and implant survival rates ranged between 95% and 100%. The literature search on BRONJ including guidelines and recommendations found 59 papers, from which six were retrieved. Among the guidelines, there is a consensus on contraindicating implants in cancer patients under IV-BPs and not contraindicating dental implants in patients under oral-BPs for osteoporosis. CONCLUSIONS: From the analysis of the one prospective and the three retrospective series (217 patients), the placement of an implant may be considered a safe procedure in patients taking oral BPs for <5 years with regard to the occurrence of BRONJ since in these studies no BRONJ has been reported. Moreover, the intake of oral-BPs did not influence short-term (1-4 years) implant survival rates.

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OBJECTIVE: To evaluate the safety and efficacy of 2 doses of dexamethasone intravitreal implant (DEX implant) for treatment of noninfectious intermediate or posterior uveitis. METHODS: In this 26-week trial, eyes with noninfectious intermediate or posterior uveitis were randomized to a single treatment with a 0.7-mg DEX implant (n = 77), 0.35-mg DEX implant (n = 76), or sham procedure (n = 76). MAIN OUTCOME MEASURE: The main outcome measure was the proportion of eyes with a vitreous haze score of 0 at week 8. RESULTS: The proportion of eyes with a vitreous haze score of 0 at week 8 was 47% with the 0.7-mg DEX implant, 36% with the 0.35-mg DEX implant, and 12% with the sham (P < .001); this benefit persisted through week 26. A gain of 15 or more letters from baseline best-corrected visual acuity was seen in significantly more eyes in the DEX implant groups than the sham group at all study visits. The percentage of eyes with intraocular pressure of 25 mm Hg or more peaked at 7.1% for the 0.7-mg DEX implant, 8.7% for the 0.35-mg DEX implant, and 4.2% for the sham (P > .05 at any visit). The incidence of cataract reported in the phakic eyes was 9 of 62 (15%) with the 0.7-mg DEX implant, 6 of 51 (12%) with the 0.35-mg DEX implant, and 4 of 55 (7%) with the sham (P > .05). CONCLUSIONS: In patients with noninfectious intermediate or posterior uveitis, a single DEX implant significantly improved intraocular inflammation and visual acuity persisting for 6 months. Application to Clinical Practice Dexamethasone intravitreal implant may be used safely and effectively for treatment of intermediate and posterior uveitis. Trial Registration clinicaltrials.gov Identifier: NCT00333814.

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Visual implant elastomer (VIE) has recently been employed to investigate different aspects of earthworm ecology. However, a number of fundamental questions relating to the detection and positioning of the tag, its persistence and potential effects on earthworms remain unknown. Seven earthworm species belonging to three ecological groupings, with different pigmentation and burrowing behaviour, were tagged using different coloured VIE. External inspection after two days, one week and 1, 10 and 27 months were followed by preservation, dissection and internal inspection. Tags could be seen in living specimens to 27 months, and dissection revealed that in most cases they were lodged in the coelomic cavity, held in place by septa. However, over longer time periods (more than two years), the chlorogogenous tissue tended to bind to the tags and made external observation increasingly difficult. Migration of the VIE material towards the posterior of the earthworm and potential loss of the tag were only observed on rare occasions, and a recovery rate in excess of 98% was recorded. By introducing a reasonable amount of VIE into segments, just after the clitellum, this technique can become a valuable tool in earthworm ecology and life history studies, particularly in short-medium term laboratory and field experiments.

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PURPOSE: To study prospectively the success rate and complications of deep sclerectomy with collagen implant (DSCI). SETTING: Glaucoma Unit, Department of Ophthalmology, Hôpital Ophtalmique Jules Gonin, University of Lausanne, Lausanne, Switzerland. METHODS: This nonrandomized prospective trial comprised 105 eyes of 105 patients with medically uncontrolled primary and secondary open-angle glaucoma. Visual acuity, intraocular pressure (IOP), and slitlamp examinations were performed before surgery and after surgery at 1 and 7 days, and 1, 3, 6, 9, 12, 18, 24, 30, 36, 48, 54, 60, 66, 72, 78, 84, 90, and 96 months. Visual field examinations were repeated every 6 months. RESULTS: Mean follow-up period was 64 months +/- 26.6 (SD). Mean preoperative IOP was 26.8 +/- 7.7 mm Hg, and mean postoperative IOP was 5.2 +/- 3.35 mm Hg at day 1 and 12 +/- 3 mm Hg at month 78. At 96 months, the qualified success rate (ie, patients who achieved IOP <21 mm Hg with and without medication) was 91%, and the complete success rate (ie, IOP <21 mm Hg without medication) was 57%. At 96 months, 34% of patients had an IOP <21 mm Hg with medication. Fifty-one patients (49%) achieved an IOP < or =15 mm Hg without medication. Neodymium:YAG goniopuncture was performed in 54 patients (51%); mean time of goniopuncture performance was 21 months, and mean IOP before goniopuncture was 20 mm Hg, dropping to 11 mm Hg after goniopuncture. No shallow or flat anterior chamber, endophthalmitis, or surgery-induced cataract was observed. However, 26 patients (25%) showed a progression of preexisting senile cataract (mean time 26 months; range 18 to 37 months). Injections of 5-fluorouracil were administered to 25 patients (23%) who underwent DSCI to salvage encysted blebs. Mean number of medications per patient was reduced from 2.3 +/- 0.7 to 0.5 +/- 0.7 (signed rank P<.0001). CONCLUSION: Deep sclerectomy with collagen implant appears to provide stable and reasonable control of IOP at long-term follow-up with few immediate postoperative complications.

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Three cases are reported of salmonella aortitis observed in three men aged 55, 60 and 48 years, the last of whom had a prosthetic aortic valve and ascending aorta. The microorganisms were S. typhi murium, S. paratyphi B, and S. wien. Despite antibiotic treatment two patients died of perforating aortitis. The third patient developed S. wien gastroenteritis a few days after surgical replacement of the aortic valve and the ascending aorta. Five years later he presented with several bacteremic episodes due to S. wien, which recurred despite several courses of cotrimoxazole treatment. He has now been asymptomatic for over one year under prolonged cotrimoxazole treatment. Since vascular infection may occur following non typhi salmonellosis in 5% of patients over 50, or who have underlying endothelial lesions, the question arises as to whether non typhi S. gastroenteritis should be treated with antibiotics in these high risk patients, in contrast to present recommendations.

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PURPOSE: To evaluate the safety and efficacy of an intravitreal fluocinolone acetonide (FA) implant compared with standard therapy in subjects with noninfectious posterior uveitis (NIPU). DESIGN: Randomized, controlled, phase 2b/3, open-label, multicenter superiority trial. PARTICIPANTS: Subjects with unilateral or bilateral NIPU. METHODS: One hundred forty subjects received either a 0.59-mg FA intravitreal implant (n = 66) or standard of care (SOC; n = 74) with either systemic prednisolone or equivalent corticosteroid as monotherapy (> or =0.2 mg/kg daily) or, if judged necessary by the investigator, combination therapy with an immunosuppressive agent plus a lower dose of prednisolone or equivalent corticosteroid (> or =0.1 mg/kg daily). MAIN OUTCOME MEASURES: Time to first recurrence of uveitis. RESULTS: Eyes that received the FA intravitreal implant experienced delayed onset of observed recurrence of uveitis (P<0.01) and a lower rate of recurrence of uveitis (18.2% vs. 63.5%; P< or =0.01) compared with SOC study eyes. Adverse events frequently observed in implanted eyes included elevated intraocular pressure (IOP) requiring IOP-lowering surgery (occurring in 21.2% of implanted eyes) and cataracts requiring extraction (occurring in 87.8% of phakic implanted eyes). No treatment-related nonocular adverse events were observed in the implant group, whereas such events occurred in 25.7% of subjects in the SOC group. CONCLUSIONS: The FA intravitreal implant provided better control of inflammation in patients with uveitis compared with systemic therapy. Intraocular pressure and lens clarity of implanted eyes need close monitoring in patients receiving the FA intravitreal implant.

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Reconstruction of defects in the craniomaxillofacial (CMF) area has mainly been based on bone grafts or metallic fixing plates and screws. Particularly in the case of large calvarial and/or craniofacial defects caused by trauma, tumours or congenital malformations, there is a need for reliable reconstruction biomaterials, because bone grafts or metallic fixing systems do not completely fulfill the criteria for the best possible reconstruction methods in these complicated cases. In this series of studies, the usability of fibre-reinforced composite (FRC) was studied as a biostable, nonmetallic alternative material for reconstructing artificially created bone defects in frontal and calvarial areas of rabbits. The experimental part of this work describes the different stages of the product development process from the first in vitro tests with resin-impregnated fibrereinforced composites to the in vivo animal studies, in which this FRC was tested as an implant material for reconstructing different size bone defects in rabbit frontal and calvarial areas. In the first in vitro study, the FRC was polymerised in contact with bone or blood in the laboratory. The polymerised FRC samples were then incubated in water, which was analysed for residual monomer content by using high performance liquid chromatography (HPLC). It was found that this in vitro polymerisation in contact with bone and blood did not markedly increase the residual monomer leaching from the FRC. In the second in vitro study, different adhesive systems were tested in fixing the implant to bone surface. This was done to find an alternative implant fixing system to screws and pins. On the basis of this study, it was found that the surface of the calvarial bone needed both mechanical and chemical treatments before the resinimpregnated FRC could be properly fixed onto it. In three animal studies performed with rabbit frontal bone defects and critical size calvarial bone defect models, biological responses to the FRC implants were evaluated. On the basis of theseevaluations, it can be concluded that the FRC, based on E-glass (electrical glass) fibres forming a porous fibre veil enables the ingrowth of connective tissues to the inner structures of the material, as well as the bone formation and mineralization inside the fibre veil. Bone formation could be enhanced by using bioactive glass granules fixed to the FRC implants. FRC-implanted bone defects healed partly; no total healing of defects was achieved. Biological responses during the follow-up time, at a maximum of 12 weeks, to resin-impregnated composite implant seemed to depend on the polymerization time of the resin matrix of the FRC. Both of the studied resin systems used in the FRC were photopolymerised and the heat-induced postpolymerisation was used additionally.

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PURPOSE: To evaluate the clinical outcome of patients who received a Baerveldt implant for refractory glaucoma and to identify factors which may influence the outcome. METHODS: Retrospective study including 51 eyes of 51 patients with medically uncontrolled glaucoma who underwent Baerveldt implant surgery between June 1994 and December 1998. Criteria for success were intraocular pressure (IOP) < or = 21 mmHg and > 6 mmHg, necessity of further antiglaucoma medications, absence of additional glaucoma surgery and no loss of light perception. RESULTS: Over a mean follow-up of 37.6 (SD: +/-18.8) months, the mean intraocular pressure decreased from 34.8 (+/-12.5) mmHg to 14.0 (+/-4.3) mmHg at month 60. Qualified success rate, achieved when IOP was below 21 mmHg and higher than 6 mmHg with medications was 25/48 (52%), complete success rate (same IOP limits without medication) was 14/48 (29%). Seven eyes had major complications or lost light perception. Postoperative visual acuity improved or remained within one Snellen line of the preoperative visual acuity in 35 patients (73%). Factors associated with a better prognosis were a preoperative visual acuity better than 20/400 and etiology of glaucoma. CONCLUSION: The Baerveldt implant is effective in lowering intraocular pressure in most patients with refractory glaucoma. Long-term results are promising with satisfactory IOP control.

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PURPOSE: To compare the efficacy and safety of T-Flux implant versus Healon GV in deep sclerectomy. METHODS: Randomized prospective trial of 23 eyes of 20 patients with medically uncontrolled open angle glaucoma over a period of 24 months, who underwent deep sclerectomy with either Healon GV or T-Flux implant. RESULTS: Mean postoperative intraocular pressure was 13.2 +/- 3.0 mm Hg with T-Flux implant (group 1) and 12.2 +/- 3.5 mm Hg with Healon GV (group 2), with a pressure reduction of 53.0% in group 1 (13.2 mm Hg vs. 28.1 mm Hg) and of 48.1% in group 2 (12.2 mm Hg vs. 23.5 mm Hg). Qualified and complete successes were 100% and 95.4% respectively. Pressures equal to or less than 15 mm Hg were 81.8% in group 1 and 90.9% in group 2 with or without treatment, and 63.6% in group 1 and 81.8% in group 2 without treatment. The number of glaucoma treatments dropped from 2.5 +/- 0.9 to 0.4 +/- 0.7 in group 1 and from 2.2 +/- 1.0 to 0.2 +/- 0.4 in group 2. The goniopuncture rate was 63.6% in group 1 and 36.4% in group 2, with a mean pressure drop of 6.1 +/- 3.9 mm Hg and 3.25 +/- 1.2 mm Hg respectively. Overall, slit-lamp diagnosed surgery-related complications included positive Seidel (13.6%), hyphaema (22.7%), choroidal detachment, and iris incarceration (4.5% each). At 2 years, ultrasound biomicroscopy showed mainly low reflective (40.1%) and flattened (36.4%) blebs. Principally latter ones were associated with the need for adjunctive treatment. A hypoechoic area in the suprachoroidal space was seen in at least 59.1% of eyes at 2 years and was not associated with lower intraocular pressure. CONCLUSION: Deep sclerectomy is an effective and safe surgery. However, longer follow up and larger study groups are required to assess the additional benefit of nonabsorbable implants.

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Dans la th´eorie des repr´esentations modulaires des groupes finis, les modules d?endo-permutation occupent une place importante. En e_et, c?est le r?ole jou´e par ces modules dans l?analyse de la structure de certains modules simples pour des groupes finis p-nilpotents, qui a amen´e E. Dade `a en introduire le concept, en 1978. Quelques ann´ees plus tard, L. Puig a d´emontr´e que la source de n?importe quel module simple pour un groupe fini p-r´esoluble quelconque est un module d?endo-permutation. Plus r´ecemment, on s?est rendu compte que ces modules interviennent aussi dans l?analyse locale des cat´egories d´eriv´ees et dans l?´etude des syst`emes de fusion. La situation que l?on consid`ere est la suivante. On se donne un nombre premier p, un p-groupe fini P, un corps alg´ebriquement clos k de caract´eristique p et on veut d´eterminer tous les kP-modules d?endo-permutation couverts ind´ecomposables de type fini, c?est-`a-dire tous les kP-modules ind´ecomposables de type fini, tels que leur alg`ebre d?endomorphismes est un kP-module de permutation ayant un facteur direct trivial. On d´efinit une relation d?´equivalence sur l?ensemble de ces kP-modules et le produit tensoriel des modules induit une structure de groupe ab´elien sur l?ensemble des classes d?´equivalence. On appelle ce groupe, le groupe de Dade de P. Ainsi, classifier les modules d?endo-permutation couverts revient `a d´eterminer le groupe de Dade de P. Le groupe de Dade d?un p-groupe fini arbitraire est encore inconnu, bien qu?E. Dade, en 1978, ´etait d´ej`a parvenu `a la classification dans le cas o`u P est ab´elien. La premi`ere partie de ce travail de th`ese est consacr´ee au probl`eme de la classification dans le cas g´en´eral et r´esoud la question dans le cas de deux familles de p-groupes finis, `a savoir celle des p-groupes m´etacycliques, pour un nombre premier p impair, et celle des 2-groupes extrasp´eciaux, de la forme D8 _ · · · _ D8. Ces deux choix ont ´et´e motiv´es par le fait que ces groupes sont "presque" ab´eliens. De plus, certains r´esultats sur la structure du groupe de Dade d?un p-groupe fini quelconque rendent le groupe de Dade des groupes de ces deux familles plus simple `a ´etudier. Dans un deuxi`eme temps, nous nous sommes int´eress´es `a deux occurrences de ces modules dans la th´eorie de la repr´esentation des groupes finis, c?est-`a-dire `a deux raisons qui motivent leur ´etude. Ainsi, nous avons r´ealis´e des modules d?endo-permutation comme sources de modules simples. En particulier, il s?av`ere que, dans le cas d?un nombre premier p impair, tout module d?endo-permutation ind´ecomposable dont la classe est un ´el´ement de torsion dans le groupe de Dade est la source d?un module simple. Finalement, nous avons d´etermin´e, parmi tous les modules d?endo-permutation connus actuellement, lesquels poss`edent une r´esolution de permutation endo-scind´ee. Nous sommes arriv´es `a la conclusion que les seuls modules d?endo-permutation qui n?ont pas de r´esolution de permutation endo-scind´ee sont les modules "exceptionnels" apparaissant pour un 2-groupe de quaternions g´en´eralis´es.<br/><br/>In modular representation theory, endo-permutation modules occupy an important position. Indeed, the role that these modules play, in the analysis of the structure of some particular simple modules for finite p-nilpotent groups, induced E. Dade, in 1978, to give them their current name. A few years later, L. Puig proved that the source of any simple module for any finite psolvable group is an endo-permutation module. More recently, the occurrence of endo-permutation modules has also been noticed in the local analysis of splendid equivalences between derived categories and in the study of fusion systems. We consider the following situation. Given a prime number p, a finite pgroup P and an algebraically closed field k of characteristic p, we are looking for all finitely generated indecomposable capped endo-permutation kP-modules. That is, all finitely generated indecomposable kP-modules such that their endomorphism algebra is a permutation kP-module having a trivial direct summand. Then, we define an equivalence relation on the set of all isomorphism classes of such modules, and it turns out that the tensor product (over k) induces a structure of abelian group on this set. We call this group the Dade group of P. Hence, classifying all indecomposable finitely generated capped endo-permutation kPmodules is equivalent to determining the Dade group of P. At present, the Dade group of an arbitrary finite p-group is still unknown. However, E. Dade computed the Dade group of all finite abelian p-groups, in 1978 already. The first part of this doctoral thesis is concerned with the problem of the classification in the general case and solve it in the case of two families of finite p-groups, namely the metacyclic p-groups, for an odd prime number p, and the extraspecial 2-groups of the shape D8 _· · ·_D8. These two choices have been motivated by the fact that these groups are not far from being abelian. Moreover, some general results concerning the Dade group of arbitrary finite p-groups suggest that the Dade group of the groups belonging to these two families is easier to study. In the second part of this thesis, we have been looking at two particular occurrences of these modules in representation theory of finite groups which motivate the interest of their classification. Thus, we realised endo-permutation modules as sources of simple modules. In particular, it turns out that, in case p is an odd prime, any indecomposable module whose class in the Dade group is a torsion element is the source of some simple module. Finally, we considered all the modules we know at present and determined which ones have an endo-split permutation resolution. We could then conclude that all but the "exceptionnal" modules occurring in the generalized quaternion case have an endo-split permutation resolution.<br/><br/>"Module d?endo-permutation" n?est pas le nom d?une maladie exotique contagieuse (du moins pas `a ma connaissance), comme vous pourriez peut-?etre l?imaginer si vous faites partie des personnes qui croient que le titre de docteur n?est destin´e qu?aux m´edecins. Dans ce cas, il se peut que le sujet dont il est question ici vous cause quelques naus´ees et r´eveille de douloureux souvenirs d?´ecole, car un module d?endo-permutation est un objet math´ematique, alg´ebrique, plus pr´ecis´ement. Ce concept a ´et´e introduit il y a un quart de si`ecle, de l?autre c?ot´e de l?Atlantique, et il s?est r´ev´el´e su_samment int´eressant pour qu?aujourd?hui il ait franchi bien des fronti`eres, celles de l?alg`ebre y compris. Mais de quoi s?agit-il ? Si vous entendez le terme "endo-permutation" probablement pour la premi`ere fois, ce n?est certainement pas le cas pour celui de "module". Cependant, sa d´efinition dans le pr´esent contexte ne co¨ýncide avec aucune de celles figurant dans les dictionnaires ordinaires. Les personnes qui ont d´ej`a entendu parler de Frobenius, Burnside, Schur, ou encore Brauer, pourront vous dire qu?un module est une repr´esentation. "De quoi ?" vous demanderezvous. "Un spectacle de marionnettes, peut-?etre ?" Bien s?ur que non ! Un module d?endo-permutation est une repr´esentation particuli`ere de certains groupes finis, o`u un groupe n?est pas un groupe de rock, comme vous pouvez vous en douter, mais d´esigne un objet math´ematique connu par tous les ´etudiants en sciences au terme de leur premi`ere ann´ee universitaire (en th´eorie, du moins). La "popularit´e" de la notion de groupe, fini ou non, est due au fait que les groupes sont fr´equemment utilis´es, aussi bien dans le domaine abstrait des math´ematiques, que dans le monde r´eel des physiciens, chimistes et autres biologistes (pour ne citer qu?eux). "Mais comment peut-on utiliser concr`etement ces objets invisibles ?" vous demanderez-vous alors. Et bien, justement, en les consid´erant par l?interm´ediaire de leurs repr´esentations, c?est-`a-dire en leur associant des matrices, de fa¸con plus ou moins naturelle. Or, comme il y a "beaucoup trop" de matrices pour un groupe donn´e, elles sont classifi´ees selon certaines de leurs propri´et´es, ce qui permet de les r´epertorier dans diverses familles (celle des modules d?endo-permutation, par exemple). Un groupe est ainsi rendu "concret", car les donn´ees matricielles sont manipulables par tous les scienti- fiques (et leurs ordinateurs), qui peuvent alors les utiliser dans leurs recherches, afin de contribuer au progr`es de la science. En toute franchise, c?est bien loin de ces soucis terre-`a-terre que ce travail de th`ese sur la classification des modules d?endo-permutation a ´et´e accompli. En fait, quitte `a choquer certaines ?ames sensibles, sa r´ealisation est surtout due au caract`ere ´epicure de son auteur, qui, avouons-le, en a ´et´e pleinement satisfait !

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Implant fracture is an infrequent cause of implant failure. The present study evaluates 21 fractured implants, with an analysis of patient age and sex, the type, length and diameter of the implant, positioning in the dental arch, the type of prosthetic rehabilitation involved, the number of abutments and pontics, the presence or absence of distal extensions or cantilevers, and loading time to fracture. Implant fracture was more common in males than in females (15:4), and the mean patient age was 56.9 years. Most cases (n = 19) corresponded to implant-supported fixed prostheses - 16 with cantilevers of different lengths- while only two fractured implants were supporting overdentures instead of fixed prostheses. The great majority of fractured implants (80.9%) were located in the molar and premolar regions, and most fractured within 3-4 years after loading. It is important to know and apply the measures required to prevent implant fracture, and to seek the best individualized solution for each case - though complete implant removal is usually the treatment of choice