Oclusão em prótese sobre implante - parte I

Osseointegrated implants have specific nature distinguish them from natural teeth making them more susceptible to the efforts generated by mastication. The absence of periodontal ligament, which absorbs the masticatory forces and allows the movement of the teeth interfere with the reception of occlusal loads and therefore the predictability of implants. In the boneimplant interface did not occur the phenomena of dissipation of impact, even the movement induced. Thus, during planning and installation of implant prosthesis, the type and characteristics of occlusal pattern adopted should be established with criteria to be no grounds for future failures. In this regard we highlight the occlusal overload generated by several reasons like the presence of premature contacts, interference during motion excursive, deleterious habits and inappropriate extensions on cantilevers. Thus, the objective is to provide a review of the literature regarding the importance of occlusion in oral rehabilitation with implants. Factors to be considered in establishing a favorable occlusion, consistent with prostheses on implants will be described

Oclusão em prótese sobre implante - parte II

In part I of this article, the factors related to the establishment of a favourable occlusion for the implant prosthodontics as well as its real importance in this kind of rehabilitation were showed up. However, it is known that the occlusal characteristics adopted in implant prosthodontics show specific patterns which must be different between each other in accordance to the type of prosthesis installed. The objective of the second part of this work is to present to the reader, by a literature review, those characteristics, justifying the reason because they must be associated to specific kind of prosthesis for favor the treatment established.

Prótese de palato em sujeitos com disfunção velofaríngea: expectativa e ansiedade

Cleft lip and palate (CLL) is a very common craniofacial anomaly. The cleft is usually corrected with surgery which may fail resulting in velopharyngeal dysfunction (VPD). The use of palatal prosthesis is an alternative treatment for correcting both, CLP and VPD. This study evaluated anxiety symptoms expectations of subjects of both genders, with velopharyngeal dysfunction, referred to palatal prosthesis program for VPD treatment. In this cross sectional and descriptive study 30 subjects with velopharyngeal dysfunction, aged 15 to 64 years old (mean age of 28) were interviewed at the Hospital for Rehabilitation of Craniofacial Anomalies (HRAC). All subjects referred to the palatal prosthesis program at HRAC in the year of 2005 were considered for participation in the study but only the first 30 candidates were included. A questionnaire addressing expectation elaborated by the researcher and the Beck Scale on anxiety were used. All subjects showed expectation regarding speech modification. Changes in professional and affective aspects of their lives after changes in speech were obtained with palatal prosthesis were the most reported expectations. Subjects’ age and gender influenced anxiety levels significantly which were minimum across subjects. High levels of expectation were more frequent than anxiety in the sample population.

Avaliação do uso de uma estrutura de nylon modificada como reforço de prótese totalmente acrílica implantossuportada

Pós-graduação em Odontologia Restauradora - ICT

Estudo clínico randomizado do movimento da prótese total superior durante a mastigação em usuários de overdentures mandibulares retidas por um ou dois implantes

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Influência da incorporação de nanofibras de poliamida 6 com e sem nanotubos de carbono como reforço de prótese parcial fixa adesiva

The aim of this study was to evaluate the behavior of reinforced composites with polyamide 6 fibers aligned (6000 rpm) and alignment (120 rpm) with or without CNT using the flexural strength test. After preparation of nanofibers aligned nylon 6 (6000 rpm) and alignment (120 rpm) with and without incorporation of nanotube carbon by the method of electrospinning, were performed one control group (n = 10) and 4 experimental groups (n = 40) G1: Control (just resin Charisma - Heraeus Kulzer) ;G2 Resin + N6 aligned (6000 rpm) + CNT; G3:Resin + N6 alignment (120 rpm) + CNT; G4: Resin + aligned ( 6000 rpm) N6. G5: Resin + N6 alignment (120 rpm). The fibers were cut to the dimensions of 0,3 x 15 mm and were applied an adhesive at the surface (Single Bond 2) for 5 min and cured. In the matrix, was added resin in the proximal box (Charisma A2, Heraeus Kulzer) and cured for 40 s. (power 1100 mW / cm²). A first layer of resin and on the resin was deposited. The resin layers specimens were light irradiated with three overlapping exposures delivered. For each resin layer were light irradiated for 40 sec. The samples were tested with a cross-speed of 1 mm / min, and a 50 Kgf at Universal testing machine (EMIC mod.DL2000). The Dunnet test showed that only the nanotube group was significantly different from the control group. The ANOVA two-way indicates that the nanotube factor was statistically significant (p < 0.05) and there is no interaction between factors and orientation nanotube. The presence of nanotube showed lower fracture resistance values for aligned and unaligned groups. The results of this study showed that the orientation of the fibers does not influence the strength of composite resins and the incorporation of nylon nanofibers with carbon nanotubes decreased the fracture resistance values. The presence of the fibers has not been able to improve the strength of the material in any of the...

Influência da incorporação de nanofibras de poliamida 6 com e sem nanotubos de carbono como reforço de prótese parcial fixa adesiva

The aim of this study was to evaluate the behavior of reinforced composites with polyamide 6 fibers aligned (6000 rpm) and alignment (120 rpm) with or without CNT using the flexural strength test. After preparation of nanofibers aligned nylon 6 (6000 rpm) and alignment (120 rpm) with and without incorporation of nanotube carbon by the method of electrospinning, were performed one control group (n = 10) and 4 experimental groups (n = 40) G1: Control (just resin Charisma - Heraeus Kulzer) ;G2 Resin + N6 aligned (6000 rpm) + CNT; G3:Resin + N6 alignment (120 rpm) + CNT; G4: Resin + aligned ( 6000 rpm) N6. G5: Resin + N6 alignment (120 rpm). The fibers were cut to the dimensions of 0,3 x 15 mm and were applied an adhesive at the surface (Single Bond 2) for 5 min and cured. In the matrix, was added resin in the proximal box (Charisma A2, Heraeus Kulzer) and cured for 40 s. (power 1100 mW / cm²). A first layer of resin and on the resin was deposited. The resin layers specimens were light irradiated with three overlapping exposures delivered. For each resin layer were light irradiated for 40 sec. The samples were tested with a cross-speed of 1 mm / min, and a 50 Kgf at Universal testing machine (EMIC mod.DL2000). The Dunnet test showed that only the nanotube group was significantly different from the control group. The ANOVA two-way indicates that the nanotube factor was statistically significant (p < 0.05) and there is no interaction between factors and orientation nanotube. The presence of nanotube showed lower fracture resistance values for aligned and unaligned groups. The results of this study showed that the orientation of the fibers does not influence the strength of composite resins and the incorporation of nylon nanofibers with carbon nanotubes decreased the fracture resistance values. The presence of the fibers has not been able to improve the strength of the material in any of the...

Surdez pós-lingual: benefícios do implante coclear versus prótese auditiva convencional

Devido aos avanços na tecnologia dos implantes cocleares e das estratégias de processamento, indivíduos com surdez grave a profunda puderam ouvir sons e reconhecer fala em diferentes graus. A variabilidade nos resultados audiológicos em portadores de surdez pós-lingual tem sido grande e a indicação para o implante coclear tem se estendido e inclui uma população cada vez maior. OBJETIVO: Avaliar em quais pacientes portadores de surdez pós-lingual o implante coclear traz benefício auditivo superior ao da prótese auditiva convencional. MATERIAIS E MÉTODOS: consulta a artigos científicos por busca no banco de dados SciELO, Cochrane, MEDLINE e LILACS-BIREME. Foram selecionadas publicações com força de evidência A ou B até a data da investigação, que comparassem aparelhos de amplificação sonora e implante coclear na população com surdez pós-lingual. Desenho do Estudo: revisão sistemática. RESULTADOS: Entre os 2169 artigos consultados, 11 trabalhos se mostram pertinentes ao tema e apresentaram força de evidência B. Seis estudos são do tipo coorte prospectivo, quatro são estudos transversais e um ensaio clinico. CONCLUSÃO: A avaliação dos benefícios obtidos por portadores de surdez pós-lingual reabilitados com o uso de implante coclear mostra que este dispositivo é efetivo e apresenta melhores resultados quando comparado aos aparelhos de amplificação sonora individual.

Surdez pré-lingual: benefícios do implante coclear versus prótese auditiva convencional

INTRODUÇÃO: A maioria dos pacientes com perda auditiva, incluindo casos de perdas severas, é beneficiada com o uso de aparelho de amplificação sonora individual. Acredita-se que o implante coclear estabeleça melhores resultados na reabilitação de uma criança com perda auditiva nos casos em que a gravidade da deficiência torna os aparelhos acústicos convencionais incapazes de fornecer informação sonora adequada, já que estes necessitam de reserva coclear suficiente para que ocorra detecção acústica. OBJETIVO: Avaliar se em pacientes portadores de surdez pré-lingual o implante coclear traz benefício auditivo superior ao da prótese auditiva convencional. SÍNTESE DOS DADOS: Revisão sistemática realizada a partir de consulta a artigos científicos selecionados por busca no banco de dados SciELO, Cochrane, MEDLINE e LILACS-BIREME. Entre os 2169 artigos consultados, 12 trabalhos se mostram pertinentes ao tema e apresentaram força de evidência B. Entre os desenhos de estudos analisados na revisão, 7 são do tipo coorte prospectivo e 5 são estudos transversais. CONCLUSÃO: O implante coclear demonstrou, através de diversos estudos, ser atualmente, a melhor alternativa para os casos de perdas auditivas bilaterais severas ou profundas, atingindo resultados superiores em percepção e desenvolvimento de fala em crianças pré-linguais quando comparados aos aparelhos de amplificação sonora convencionais.

Deleterious outcome of No-React-treated stentless valved conduits after aortic root replacement: why were warnings ignored?

OBJECTIVE: The implantation of a composite graft is the treatment of choice for patients with aortic root disease if the valve cannot be preserved and the patient is not a suitable candidate for a Ross procedure. Several years ago, the Shelhigh NR-2000C (Shelhigh, Inc, Millburn, NJ) was introduced in Europe. Being a totally biologic conduit and considering the lack of homografts, the graft seemed an ideal conduit for patients with destructive endocarditis, as well as for older patients who were not suitable candidates for oral anticoagulation. METHODS: From 2001 until 2006, the Shelhigh NR-2000C stentless valved conduit was implanted in 115 patients for various aortic root pathologies. The conduit consists of a bovine pericardial straight graft with an incorporated porcine stentless valve. Aortic root repair was performed during standard cardiopulmonary bypass and mild hypothermia in the majority of patients. Deep hypothermic circulatory arrest combined with selective antegrade cerebral perfusion was used when the repair extended into the arch. RESULTS: Seven patients with uncomplicated early outcome presented with unexpected sudden disastrous findings at the level of the aortic root, although 1-year follow-up computed tomographic scans were normal. Four of these patients underwent emergency operations because of desintegration of the graft, along with rupture of the aortic root. Retrospectively, the main findings were persistent fever or subfebrility over months and a halo-like enhancement on computed tomographic scans. Extensive microbiologic examinations were performed without finding a causative organism. CONCLUSION: The use of the Shelhigh aortic stentless conduit can no longer be advocated, and meticulous follow-up of patients in whom this device has been implanted has to be recommended.

Pitfalls and premature failure of the Freedom SOLO stentless valve.

OBJECTIVES This study reports a series of pitfalls, premature failures and explantations of the third-generation Freedom SOLO (FS) bovine pericardial stentless valve. METHODS A total of 149 patients underwent aortic valve replacement using the FS. Follow-up was 100% complete with an average observation time of 5.5 ± 2.3 years (maximum 8.7 years) and a total of 825 patient-years. Following intraoperative documentation, all explanted valve prostheses underwent histological examination. RESULTS Freedom from structural valve deterioration (SVD) at 5, 6, 7, 8 and 9 years was 92, 88, 80, 70 and 62%, respectively. Fourteen prostheses required explantation due to valve-independent dysfunction (n = 5; i.e. thrombus formation, oversizing, aortic dilatation, endocarditis and suture dehiscence) or valve-dependent failure (acute leaflet tears, n = 4 and severe stenosis, n = 5). Thus, freedom from explantation at 5, 6, 7, 8 and 9 years was 95, 94, 91, 81 and 72%, respectively. An acute vertical tear along the non-coronary/right coronary commissure to the base occurred at a mean of 6.0 years (range 4.3-7.3 years) and affected size 25 and 27 prostheses exclusively. Four FS required explantation after a mean of 7.5 years (range 7.0-8.3 years) due to severe functional stenosis and gross calcification that included the entire aortic root. CONCLUSIONS The FS stentless valve is safe to implant and shows satisfying mid-term results in our single institution experience. Freedom from SVD and explantation decreased markedly after only 6-7 years, so that patients with FS require close observation and follow-up. Exact sizing, symmetric positioning and observing patient limitations are crucial for optimal outcome.