Quality of life and satisfaction of patients wearing implant-supported fixed partial denture: a cross-sectional survey of patients from Araçatuba city, Brazil.

OBJECTIVES: The aim of this study was to evaluate the quality of life and satisfaction of patients wearing implant-supported fixed partial dentures. MATERIALS & METHODS: A total of 106 patients were selected and submitted to clinical examination and collection of the demographic data for evaluation of the implant-supported fixed dentures conditions. All participants agreed to answer to the Oral Health Impact Profile (OHIP-EDENT) questionnaire and another questionnaire about satisfaction with the implant-supported prostheses. The patients were classified into the following three groups for statistical analysis: patients wearing splinted implant-supported prosthesis (E), patients wearing single implant-supported prosthesis (U), and patients wearing single implant-supported prosthesis associated with splinted prosthesis (E + U). Kruskal-Wallis test was used to compare the answers between the groups, and a logistic regression model was measured to verify the relation between variables of the patients and the questionaries' items. RESULTS: There were significant differences among groups (P = 0.006) for discomfort during surgery itself of the satisfaction questionnaire. The marital status, groups, and hygiene condition were significant mainly for physical pain item. CONCLUSIONS: It was concluded that the patients presented high level of satisfaction and quality of life for the most of the items evaluated as well as the groups showed similar results.

Influência do material oclusal na distribuição de tensões em próteses implantossuportadas unitárias / Influence of occlusal material on stress distribution in single implant-supported prostheses

O objetivo deste estudo foi avaliar a influência do material oclusal em próteses implantossuportadas unitárias, através do método de elementos finitos 3-D. Material e Métodos: quatro modelos foram fabricados utilizando os softwares Rhinoceros 4.0, SolidWorks e InVesalius. Cada modelo representou um bloco de osso mandibular com um implante de hexágono externo de 5 mm x 10 mm e diferentes materiais oclusais, incluindo NiCr (1), porcelana (2), resina composta (3) e resina acrílica (4). Uma força axial de 200 N e uma força oblíqua de 100 N foram aplicadas. Resultados: o modelo (2) com material oclusal de porcelana apresentou menor concentração de tensões para a infraestrutura de NiCr, seguido de resina composta e resina acrílica. A distribuição de tensões para implante e tecido ósseo foi similar para todos os modelos. Conclusão: não há diferença na distribuição de tensões para implante e estruturas suportes, variando-se o material oclusal de próteses implantossuportadas unitárias...

Objective: the aim of this study was to evaluate the influence of occlusal veneering material in single fixed implant-supported crowns through the 3-D finite element method. Material and methods: Four models were fabricated using the Rhinoceros 4.0, SolidWorks, and InVesalius softwares. Each model represented a block of mandibular bone with an external hexagon implant of 5 mm x 10 mm and different veneering materials including NiCr (1), porcelain (2), composite resin (3), and acrylic resin (4). An axial load of 200 N and an oblique load of 100 N were applied. Results: model (2) with porcelain veneering presented a lower stress concentration for the NiCr framework, followed by the composite resin and acrylic resin. The stress distribution to the implant and bone tissue was similar for all models. Conclusions: there is no difference of stress distribution to the implant and supporting structures by varying the veneering material of a single implant-supported prosthesis...

Implantes platform switching: longevidade e preservação óssea: revisão crítica da literatura / Platform switching implants: longevity and preservation bone: literature critical review

O conceito de platform switching consiste na utilização de um implante com plataforma de assentamento maior do que o pilar protético. Recentemente, pesquisas revelam que este desenho de implante dentário tende a oferecer um melhor padrão de preservação da crista óssea, quando comparado ao padrão tradicional de perda óssea ao redor dos implantes. O objetivo deste estudo foi realizar uma revisão crítica sobre o tema platform switching estabelecendo as possíveis vantagens da técnica. Realizou-se uma revisão na base de dados Medline/Pubmed sobre o tema “dental implant” e “platform switching”, depois de submetido aos critérios de inclusão, selecionou-se 40 estudos. Estudos em longevidade, prospectivos apontam menor perda óssea, estudos em biomecânica apontam melhor ou semelhante distribuição de tensões ao redor da crista óssea, entretanto, ainda não está definido o papel do espaço biológico. Assim, é de grande relevância que estudos de maior longevidade e randomizados prospectivos sejam realizados, a fim de ratificar os benefícios da técnica e criar um possível protocolo de indicação. É possível, com base nesta revisão de literatura, concluir que estudos longitudinais, prospectivos e randomizados indicam que os implantes platform switching apresentam longevidade e menor perda óssea. Biomecanicamente, a técnica é viável

The concept of switching platform is the use of an implant by platform wider than the abutment. Recently, researches have shown that this type of dental implant design tends to offer a higher preservation of crestal bone when compared to the traditional pattern of bone loss. The present study aims to perform a critical review on the switching platform concept establishing possible advantages of the technique. A search was performed on Medline/Pubmed about the topic “dental implant” and “platform switching”, and after applying inclusion criteria 40 studies were selected. The literature on longevity present prospective studies that show less bone loss, studies in biomechanics exhibit better or similar stress distribution around the bone crest, however, is not yet defined the role of the biological width. Thus, studies of longevity, and randomized prospective studies are of a great relevance to be performed in order to confirm the benefits of this technique and to establish a protocol indication. It is possible, based on this literature review, to conclude that longitudinal and randomized studies show that the platform switching implants have longevity and less bone loss. Biomechanically, the technique is possible

Sistemas de retenção intrarradicular: considerações teóricas e comportamento biomecânico / Inner root retention systems: theoretical considerations and biomechanical behavior

O objetivo do presente estudo foi realizar uma revisão da literatura científica atual, a fim de discutir o comportamento biomecânico e as características inerentes tanto aos núcleos metálicos fundidos, quanto aos pinos pré-fabricados utilizados na prática restauradora dos dentes endodonticamente tratados. Para a identificação dos estudos dessa revisão, foi realizada uma estratégia de busca detalha e avançada para os bancos de dados PubMed e Medline. Foram utilizados como descritores: endodontically treated teeth, post, core, fiber post e metal post. Os critérios de inclusão foram: artigos clínicos, estudos controlados aleatórios, estudos in vitro, revisões de literatura e revisões sistemáticas com e sem meta-análise dos últimos 10 anos, que abordassem o tema proposto. Os critérios de exclusão foram: artigos sem resumo, estudos em animais, artigos cujo idioma não fosse o inglês e artigos de periódicos que não pertencessem à área odontológica. De um total de 211 artigos, após uma análise segundo o critério de inclusão e exclusão, foram selecionados 65 artigos. A maioria da literatura científica atual indica que os pinos pré-fabricados reforçados por fibras e os pinos cerâmicos deveriam ser indicados para os dentes endodonticamente tratados que apresentem uma altura mínima de 2mm de férula. Já os núcleos metálicos fundidos, juntamente com os pinos pré-fabricados metálicos representam uma boa opção protética, quando os dentes a serem restaurados apresentam-se enfraquecidos por qualquer motivo. Apesar do grande número de pesquisas, ainda há uma carência de estudos prospectivos em longo prazo que avaliem a efetividade desses pinos no tratamento de dentes tratados endodonticamente

The aim of this study was to review the current scientific literature to discuss the biomechanical behavior and characteristics inherent to both cast post and core and the prefabricated posts used in the practice of restoring endodontically treated teeth. To identify studies of this review, it was performed a detailed and advanced search strategy to the databases PubMed and Medline. It was used as descriptors: endodontically treated teeth, post, core, fiber post and metal post. Inclusion criteria were: clinical trials, randomized controlled trials, in vitro studies, literature reviews and systematic reviews with or without meta-analysis of the last 10 years that addressed the theme. Exclusion criteria were: articles without abstracts, animal studies, articles whose language was not English and articles from journals that do not belong to the Dentistry field. Of a total of 35 articles, after an analysis according to inclusion and exclusion criteria, 23 articles were selected. Most of the current scientific literature indicates that the prefabricated fiber reinforced and ceramic posts should be appointed for endodontically treated teeth that have a minimum height of 2mm ferrule. As for the cast metal cores, along with pre-fabricated metal represent a good prosthetic option, when weakened teeth have to be restored for any reason. Despite the large number of studies, there is still a lack of longterm prospective studies that evaluate the effectiveness of these posts in the treatment of endodontically treated teeth

Análise das tensões em próteses unitárias implantossuportadas com diferentes tipos de conexões e qualidade óssea: estudo pelo método dos elementos finitos tridimensionais / Stress analysis of single implant-supported prosthesis with different prosthetic connection and bone qualities: a threedimensional finite element study

Um aspecto crítico que afeta o sucesso ou falha de um implante é a maneira pela qual as tensões são transferidas do implante ao tecido ósseo. A sobrecarga na prótese dentária pode levar a perda da osseointegração, dessa forma, é aconselhável evitar altas concentrações de tensões no osso de suporte, do ponto de vista clínico. Entretanto, o estresse mecânico pode ter consequências positivas ou negativas no tecido ósseo, fatores esses dependentes de vários fatores associados que podem ser mecânicos ou biológicos. Portanto, o propósito do presente estudo foi analisar a influência da qualidade óssea na distribuição das tensões em próteses unitárias implantossuportadas com diferentes tipos de conexão protética, pelo método dos elementos finitos tridimensionais. Para isso, foram confeccionados doze modelos tridimensionais com o auxílio dos programas de modelagem gráfica SolidWorks 2010 e Rhinoceros 4.0, além do programa InVesalius. Cada modelo foi composto por um bloco com diferentes qualidades ósseas (Tipo I, II, III e IV) e a presença de um implante (4,0x10 mm) com diferente tipo de conexão (Hexágono externo, interno e cone Morse), com coroa metalo-cerâmica. Após geração de geometrias, os modelos foram importados para o programa de pré e pós processamento de elementos finitos FEMAP 10.2, onde foram geradas as malhas de elementos finitos, condições de carregamento e contorno. A carga aplicada foi de 200N axialmente e 100N obliquamente, na superfície oclusal das coroas. Essa carga total foi dividida entre as cúspides (4 para a carga axial e as duas linguais para a carga oblíqua). Em seguida, a análise foi gerada no programa FEMAP 10.2 e exportada para cálculo no programa de elementos finitos NeiNastran versão 9.2, executada em uma estação de trabalho. Os resultados foram importados novamente ao FEMAP 10.2 para visualização e pós-processamento dos mapas de tensão de von Mises e tensão máxima principal. Os mapas gerais mostraram áreas de altas tensões no local de...

A critical issue that affects the success or failure of an implant is the manner in which the stresses are transferred from the implant to bone tissue. The overload can lead the dental implant to loss of osseointegration, thus it is advisable to avoid high stress concentrations in bone support, according to the clinical point of view. However, mechanical stress can bring positive or negative consequences in the bone tissue and these factors depend on association with mechanical or biological factors. Therefore, the purpose of this study was to analyze the influence of bone quality on stress distribution in implant-prosthesis unit with different types of prosthetic connection, by the three-dimensional finite element method. For this, twelve three-dimensional models were made with the aid of SolidWorks 2010 and Rhinoceros 4.0, graphical modeling software, besides the InVesalius. Each model was composed of a block with different bone qualities (Type I, II, III and IV), an implant (4.0 x 10 mm) with different type of prosthetic connection (Hexagon external, internal and Morse taper) and metal ceramic crown. After generation of geometries, the models were imported into FEMAP 10.2, the pre and post-processing finite element software, where it was generated finite element meshes, boundary and loading conditions. The 200N load was applied axially and 100N obliquely on the occlusal surface of crowns. This total load was divided among the cusps (four points for the axial load and two points for the oblique load on the lingual cusps). Then, the analysis was generated in the FEMAP 10.2 and exported to the NeiNastran version 9.2 software for calculation in finite element analysis, running on a workstation. The results were imported back to the FEMAP 10.2 for viewing and post-processing maps of von Mises stress and maximum principal stress. The general maps showed areas of high stress at the site of force application and in the interface crown/implant. Not only the screw, as…

Análise das tensões em próteses unitárias implantossuportadas com diferentes tipos de conexões e qualidade óssea: estudo pelo método dos elementos finitos tridimensionais / Stress analysis of single implant-supported prosthesis with different prosthetic connection and bone qualities: a threedimensional finite element study

Um aspecto crítico que afeta o sucesso ou falha de um implante é a maneira pela qual as tensões são transferidas do implante ao tecido ósseo. A sobrecarga na prótese dentária pode levar a perda da osseointegração, dessa forma, é aconselhável evitar altas concentrações de tensões no osso de suporte, do ponto de vista clínico. Entretanto, o estresse mecânico pode ter consequências positivas ou negativas no tecido ósseo, fatores esses dependentes de vários fatores associados que podem ser mecânicos ou biológicos. Portanto, o propósito do presente estudo foi analisar a influência da qualidade óssea na distribuição das tensões em próteses unitárias implantossuportadas com diferentes tipos de conexão protética, pelo método dos elementos finitos tridimensionais. Para isso, foram confeccionados doze modelos tridimensionais com o auxílio dos programas de modelagem gráfica SolidWorks 2010 e Rhinoceros 4.0, além do programa InVesalius. Cada modelo foi composto por um bloco com diferentes qualidades ósseas (Tipo I, II, III e IV) e a presença de um implante (4,0x10 mm) com diferente tipo de conexão (Hexágono externo, interno e cone Morse), com coroa metalo-cerâmica. Após geração de geometrias, os modelos foram importados para o programa de pré e pós processamento de elementos finitos FEMAP 10.2, onde foram geradas as malhas de elementos finitos, condições de carregamento e contorno. A carga aplicada foi de 200N axialmente e 100N obliquamente, na superfície oclusal das coroas. Essa carga total foi dividida entre as cúspides (4 para a carga axial e as duas linguais para a carga oblíqua). Em seguida, a análise foi gerada no programa FEMAP 10.2 e exportada para cálculo no programa de elementos finitos NeiNastran versão 9.2, executada em uma estação de trabalho. Os resultados foram importados novamente ao FEMAP 10.2 para visualização e pós-processamento dos mapas de tensão de von Mises e tensão máxima principal. Os mapas gerais mostraram áreas de altas tensões no local de...

A critical issue that affects the success or failure of an implant is the manner in which the stresses are transferred from the implant to bone tissue. The overload can lead the dental implant to loss of osseointegration, thus it is advisable to avoid high stress concentrations in bone support, according to the clinical point of view. However, mechanical stress can bring positive or negative consequences in the bone tissue and these factors depend on association with mechanical or biological factors. Therefore, the purpose of this study was to analyze the influence of bone quality on stress distribution in implant-prosthesis unit with different types of prosthetic connection, by the three-dimensional finite element method. For this, twelve three-dimensional models were made with the aid of SolidWorks 2010 and Rhinoceros 4.0, graphical modeling software, besides the InVesalius. Each model was composed of a block with different bone qualities (Type I, II, III and IV), an implant (4.0 x 10 mm) with different type of prosthetic connection (Hexagon external, internal and Morse taper) and metal ceramic crown. After generation of geometries, the models were imported into FEMAP 10.2, the pre and post-processing finite element software, where it was generated finite element meshes, boundary and loading conditions. The 200N load was applied axially and 100N obliquely on the occlusal surface of crowns. This total load was divided among the cusps (four points for the axial load and two points for the oblique load on the lingual cusps). Then, the analysis was generated in the FEMAP 10.2 and exported to the NeiNastran version 9.2 software for calculation in finite element analysis, running on a workstation. The results were imported back to the FEMAP 10.2 for viewing and post-processing maps of von Mises stress and maximum principal stress. The general maps showed areas of high stress at the site of force application and in the interface crown/implant. Not only the screw, as…

Removable partial denture in combination with a milled fixed partial prosthesis as interim restorations in long-term treatment.

Interim restorations are frequently used in prosthodontic treatments. Many complex situations require the combination of fixed and removable partial prostheses. An appropriate interim restoration design that accurately implements the treatment plan is necessary to prepare the oral cavity for the prostheses, and to contribute to the preservation and health of remaining natural teeth, bone support, and gingival tissues. This report describes a modified technique for construction of interim restorations with a combination of fixed and removable partial prostheses. The technique consists of the construction of a milled fixed prosthesis and removable partial denture with metallic framework for use during extensive treatment, improving masticatory function and esthetics and preserving the periodontal health of supporting structures. This interim restoration can also serve as a template for the definitive restoration, allowing patient and dentist to evaluate appearance and function and helping to ensure the success of the definitive restoration.

Diferentes materiais oclusais no tratamento reabilitador com implantes osseointegráveis / Different oclusal materials in the oral rehabilitation with osseointegrated implants

A seleção de materiais de revestimento de próteses sobre implante é um fator biomecânico ainda pouco estudado e controverso. O objetivo deste trabalho foi realizar uma revisão que permitisse um direcionamento para o clínico. Realizou-se uma busca detalhada na base de dados Medline (Pubmed) de 1980-2009. Foram utilizados como descritores “material prosthesis dental implant”, “oclusal prosthesis dental implant”, de um total de 49 artigos selecionou-se 21. Observou-se 3 linhas de pensamentos em relação ao assunto. Existe um grupo de autores que sugere que as resinas acrílicas seriam o melhor material oclusal, outro grupo acredita não existir diferenças entre eles. Existe ainda um grupo que acredita em resultados negativos na utilização da resina. Sendo assim, não existe um consenso sobre qual seria o melhor material oclusal para dissipação de tensões no sistema implante/osso. A escolha da porcelana como primeiro material de escolha para as reabilitações parece ser mais eficiente, levando-se em consideração a higienização, estética e resistência a fratura

The selection of oclusal materials on implant-supported prosthesis is a controversial aspect and biomechanical studies are still scarce. The aim of this study was to carry out a literature review that allows guiding to the clinician. A PubMed search was carried out for the years between 1980 and 2009 identifying publications on “material prosthesis dental implant”, “occlusal prostheses dental implant”, of a total of 49 articles were selected 18. It was observed 3 lines of criteria in relation to the subject. Some authors suggested that acrylic resins would be the best oclusal material; another group believes that there not differences between the occlusal materials. On the other hand, researches believe that the use of acrylic resin material was unfavorable. Thus, there no consensus about oclusal materials in relationship to the stress distribution on bone/implant interface. The choice of porcelain material as the first alternative to oral rehabilitation should be more satisfactory, taken into account the oral hygiene, aesthetics and fracture resistance

Sistemas de encaixes em prótese parcial removível: classificação e indicação / Attachments systems in removable partial denture: classification and indications

O objetivo deste estudo foi realizar um levantamento bibliográfico apresentando os critérios de seleção e classificação dos encaixes, indicação, contra-indicação e as vantagens e desvantagens, no tratamento reabilitador. Para a identificação dos estudos considerados nesta revisão, foi realizada uma estratégia de busca detalhada no PUBMED e BIREME entre os anos 1980-2008. Utilizaram-se descritores na língua inglesa e no português: “encaixes”; “prótese parcial removível”; “attachments for removable partial denture”. Os critérios de inclusão foram: pesquisas clínicas, laboratoriais e de revisão sobre o tema. Foram excluídos os artigos técnicos (novos tipos de encaixes). Foram selecionados 25 artigos, sendo que os dados foram analisados, cruzados e debatidos para a realização da redação com os resultados concludentes. Baseado na revisão de literatura, concluiu-se que: A situação clínica para a qual um encaixe é indicado depende não só da estética, também da biomecânica e fatores biológicos que podem afetar a prótese. O sucesso clínico da terapia com prótese parcial removível utilizando encaixes requer o conhecimento das forças potenciais que uma prótese pode transferir aos dentes e ao rebordo residual. Portanto, para a correta indicação é indispensável, observar os parâmetros de indicação, contra-indicação, vantagens e desvantagens. Em próteses de extremidade livres poderia ser recomendados encaixes resilientes enquanto que nas dentossuportadas a opção poderia ser pelos rígidos

The aim of this study was to realize a review of literature about selection, classification, indication, contraindication, advantages and disadvantages of the attachments, in the treatment rehabilitation. For the search was used the databases PUBMED and BIREME, between 1980-2008. The descriptors used in english and portuguese were: “encaixes”; “prótese parcial removível”; “attachments for removable partial denture”. The inclusion criterion was: clinic research, laboratorial and review of literature and were excluded technical articles (new design of attachments). It was selectioned 25 articles, the results were analyzed and discussed. Based in the review of literature, it was concluded that: The clinical situation to use the attachments, not only depends of the aesthetic, but also, biomechanical and biological factors that affect the prostheses; the clinical success of removable partial dentures with attachments require the knowledge about potential forces that the prosthesis could transfer to the teeth and residual ridge. Therefore, a proper indication is indispensable, applying some guidelines, such as advantages, disadvantages, indications and contraindications. In distal extension removable partial dentures should be recommended resilient attachments, and tooth-supported prosthesis should be associated with rigid attachments

Esthetic interim acrylic resin prosthesis reinforced with metal casting.

Fabrication of an interim prosthesis is an important procedure in oral rehabilitation because it aids in determining the esthetics, phonetics, and occlusal relationship of the definitive restoration. The typical material (acrylic resin) used in interim prostheses commonly fails due to fractures. During extended oral rehabilitation with fixed partial prostheses, high strength interim prostheses are often required to protect hard and soft tissues, avoid dental mobility, and to allow the clinician and patient a chance to evaluate cosmetics and function before the placement of the definitive prosthesis. Furthermore, a satisfactory interim prosthesis can serve as a template for the construction of the definitive prosthesis. The maintenance of this prosthesis is important during treatment for protection of teeth and occlusal stability. Procedures to reinforce interim prostheses help to improve performance and esthetics in long-term treatment. Due to the low durability of acrylic resin in long-term use, the use of reinforcing materials, such as metal castings or spot-welded stainless steel matrix bands, is indicated in cases of extensive restoration and long-term treatment. This paper describes an easy technique for fabricating a fixed interim prosthesis using acrylic resin and a cast metallic reinforcement.

Analysis of mandibular position using different methods of location.

There has been much discussion regarding the ideal position of the condyle in the mandibular fossa. Although the centric relation position (CR) is used as a reference, some authors do not believe that it is physiologic. Thus, the aim of this study was to evaluate in a group of asymptomatic individuals the position of the condyle in the mandibular fossa at maximum intercuspation (MI), with a occlusal splint and with a Lucia jig between the teeth. It was analyzed by means of magnetic resonance imaging (MRI), transcranial radiography imaging and analysis of horizontal axis of rotation from casts mounted on an articulator. The results showed that even if patients had mandibular displacement in positions of CR, habitual maximum intercuspation and with the occlusal splint, confirmed by means of the analysis of the horizontal axis of rotation, the images showed no statistically significant differences among condylar positions. It can therefore be concluded that the positions analyzed were similar and that transcranial radiography seems to be a reliable method for analyzing condylar position.

Analysis of mandibular position using different methods of location / Análise da posição mandibular através de diferentes métodos de localização

There has been much discussion regarding the ideal position of the condyle in the mandibular fossa. Although the centric relation position (CR) is used as a reference, some authors do not believe that it is physiologic. Thus, the aim of this study was to evaluate in a group of asymptomatic individuals the position ofthe condyle in the mandibular fossa at maximum intercuspation (MI), with a occlusal splint and with a Lucia jig between the teeth. It was analyzed by means of magnetic resonance imaging (MRI), transcranial radiography imaging and analysis of horizontal axis of rotation from casts mounted on anarticulator. The results showed that even if patients had mandibular displacement in positions of CR, habitual maximum intercuspation and with the occlusal splint, confirmed by means of the analysis of the horizontal axis of rotation, the images showed no statistically significant differences amongcondylar positions. It can therefore be concluded that the positions analyzed were similar and that transcranial radiography seems to be a reliable method for analyzing condylar position.

Muito se discute sobre a posição ideal que o côndilo deve ocupar dentro da fossa mandibular. Apesar da Relação Cêntrica (RC) ser usada como uma referência, alguns autores não concordam que esta posição seja fisiológica. Sendo assim, o objetivo deste estudo foi avaliar a posição do côndilo dentro da fossa mandibular em um grupo de indivíduos assintomáticosnas posições de máxima intercuspidação (MI), com placa estabilizadora e com o Guia de Lucia, interposto entre os dentes. A análise foi realizada por meio de imagem por ressonância nuclear magnética, da radiografia transcraniana;e análise do eixo horizontal de rotação, a partir de castos montados em articulador. Os resultados mostraram que, apesar de os pacientes possuírem deslizes mandibulares entre as posiçõesde RC, máxima intercuspidação habitual e com a placa estabilizadora, confirmados por meio da análise do eixo horizontal de rotação, as imagens não mostraram diferenças estatisticamentesignificantes entre as posições condilares. Assim, pode-se concluir que as posições analisadas foram similares eque a radiografia transcranial parece ser um método confiável para análise da posição condilar.

Analysis of mandibular position using different methods of location / Análise da posiþÒo mandibular através de diferentes métodos de localizaþÒo

There has been much discussion regarding the ideal position of the condyle in the mandibular fossa. Although the centric relation position (CR) is used as a reference, some authors do not believe that it is physiologic. Thus, the aim of this study was to evaluate in a group of asymptomatic individuals the position ofthe condyle in the mandibular fossa at maximum intercuspation (MI), with a occlusal splint and with a Lucia jig between the teeth. It was analyzed by means of magnetic resonance imaging (MRI), transcranial radiography imaging and analysis of horizontal axis of rotation from casts mounted on anarticulator. The results showed that even if patients had mandibular displacement in positions of CR, habitual maximum intercuspation and with the occlusal splint, confirmed by means of the analysis of the horizontal axis of rotation, the images showed no statistically significant differences amongcondylar positions. It can therefore be concluded that the positions analyzed were similar and that transcranial radiography seems to be a reliable method for analyzing condylar position.(AU)

Muito se discute sobre a posiþÒo ideal que o c¶ndilo deve ocupar dentro da fossa mandibular. Apesar da RelaþÒo CÛntrica (RC) ser usada como uma referÛncia, alguns autores nÒo concordam que esta posiþÒo seja fisiológica. Sendo assim, o objetivo deste estudo foi avaliar a posiþÒo do c¶ndilo dentro da fossa mandibular em um grupo de indivíduos assintomáticosnas posiþ§es de máxima intercuspidaþÒo (MI), com placa estabilizadora e com o Guia de Lucia, interposto entre os dentes. A análise foi realizada por meio de imagem por ressonÔncia nuclear magnética, da radiografia transcraniana;e análise do eixo horizontal de rotaþÒo, a partir de castos montados em articulador. Os resultados mostraram que, apesar de os pacientes possuírem deslizes mandibulares entre as posiþ§esde RC, máxima intercuspidaþÒo habitual e com a placa estabilizadora, confirmados por meio da análise do eixo horizontal de rotaþÒo, as imagens nÒo mostraram diferenþas estatisticamentesignificantes entre as posiþ§es condilares. Assim, pode-se concluir que as posiþ§es analisadas foram similares eque a radiografia transcranial parece ser um método confiável para análise da posiþÒo condilar.(AU)

Avaliação da distribuição de tensões em casos de prótese parcial removível de classe 1 mandibular convencional e associada a implante osseointegrado pelo método dos elementos finitos / Evaluation of the distribution of tensions in cases of inferior removable partial denture class 1 conventional and associated with osseointegrated implant by the finite element analysis

A associação das próteses parciais removíveis (PPRs) e implantes osseointegrados tem sido relatada na literatura, mas ainda não existem relatos sobre a melhor forma de conexão com o último dente suporte nos casos de extremidade livre. Assim, o objetivo deste trabalho foi estudar, através do MEF bidimensional, o comportamento das estruturas de suporte de uma PPR convencional e associada a implante osseointegrado, agindo apenas como suporte, variando-se os sistemas de conexão com o último dente suporte entre apoio distal e placa distal. Foram confeccionados 4 modelos hemi-mandibulares, com presença apenas do dente 33, sendo: Mod A, PPR convencional e apoio distal; Mod B, PPR convencional e placa distal; Mod C, PPR associada a implante de 3,75 x 10,0 mm e apoio distal; Mod D, PPR associada a implante de 3,75 x 10,0 mm e placa distal. O programa de elementos finitos utilizados foi o ANSYS 9.0 com carregamento de 50N em cada ponta de cúspide, estritamente vertical. Os resultados foram obtidos através de mapas de deslocamento e tensão de Von Mises. Os resultados mostraram alívo do ligamento periodontal e dente suporte quando da presença da placa distal, tanto nos mapas de deslocamento quanto nos mapas de tensão. Por esta metodologia foi possível concluir que: 1. A placa distal diminuiu a tendência de movimento do dente suporte, tanto dos modelos com PPR convencional, quanto nos associados a implante; 2. Os modelos que incorporaram a placa distal melhoraram a distribuição interna de tensões de von Mises, principalmente pelo alívio do dente suporte.

The association of the removable partial dentures (RPDs) and osseointegrated implants it has been mentioned in the literature, but reports don’t still exist on the best connection form with the last support tooth in the cases of distal extension. Like this, the objective of this work was to study, through the bidimensional FEA, the behavior of the support structures of a conventional RPD and associated with implants, just acting as support, by variation in the connection systems with the last support tooth between distal incisal rest or and distal plate. 4 hemi-mandibular models were made, with presence just of the tooth 33: Model A: conventional RPD and distal incisal rest; Model B: conventional RPD and distal plate; Model C: RPD associated with implant (3,75 x 10,0 mm) and distal incisal rest; Model D: RPD associated with implant (3,75 x 10,0 mm) and distal plate. The finite element program used was ANSYS 9.0 with loading of 50N in each cusp tip, strictly vertical. The results were obtained through displacement maps and tension maps. The results showed decrease of the ligament and support tooth tension when distal plate were present, as in the displacement maps or in the tension maps. For this methodology it was possible conclude: 1. The distal plate reduced the tendency of movement of the support tooth in all models; 2. the models that incorporated the distal plate improved the internal distribution of von Mises tensions, mainly for the relief of the support tooth.

Evaluation of temporomandibular joint noise in partially edentulous patients.

In order to evaluate the presence of TMD (temporomandibular disorder), dissatisfaction related to the use of removable partial dentures (RPD) and the effect of the treatment on temporomandibular joint noises, 13 female patients with Kennedy class I and II mandibular arch were selected. Another 13 young, asymptomatic, dentate patients, also female, were used as reference. After four years, 38.4% were found to have a moderate or severe degree of TMD. Over the four years, the degree of TMD increased in 46.15% of the patients, was not affected in 20.07%, while in 15.38% it decreased or the patients remained free from signs and symptoms. About 30% of the patients at the second year and 46% after the fourth year, had complaints regarding retention and stability. It was concluded that there is no relationship between TMD and the condition of partially edentulous Kennedy class I and II, but patient dissatisfaction increased after the second year and temporomandibular joint noise was reduced significantly with the replacement of the teeth.

Evaluation of dimensional change and detail reproduction in silicones for facial prostheses.

The aim of this study was to evaluate the dimensional stability and detail reproduction of two silicones used for facial prosthesis, under the influence of chemical disinfection and storage time. Twenty-eight test specimens were obtained, half made of Silastic MDX 4-4210 silicone, and the other half of Silastic 732 RTV silicone. The test specimens were divided into 4 groups: Silastic 732 RTV and Silastic MDX 4-4210, with disinfection 3 times a week with Efferdent and without disinfection. Dimensional change was analyzed using an electronic comparison microscope and detail reproduction was observed under a stereo microscope, immediately and 2 months after the test specimens were made. Once the results were obtained, an analisis of variance (ANOVA) was applied, followed by the Tukey's Test with 1% confidence. The storage time factor had a statistical influence on dimensional stability: Silastic MDX 4-4210 had less contraction than Silastic 732 RTV. Chemical disinfection did not significantly alter the dimensional stability of the materials used. Regarding detail reproduction, no alteration of values was observed in any of the materials analyzed, regardless of storage period or disinfection.

Envelhecimento do aparelho estomatognático: alterações fisiológicas e anatômicas / Ageing of the stomatognathic system: physiologic and anatomical alterations

Com o aumento da expectativa de vida da população em todo o planeta, o número de idosos tem crescido proporcionalmente, mas sem que haja um acompanhamento das condições de saúde para esta faixa etária da população. Em virtude da heterogeneidade de condições físicas, psíquicas e sociais apresentadas por esse grupo, nem todos os profissionais apresentam-se habilitados para entender e solucionar problemas relacionados ao envelhecimento. Dessa forma, este trabalho tem por objetivo esclarecer as modificações decorrentes do envelhecimento em âmbito fisiológico e anatômico das principais estruturas do Aparelho Estomatognático associando as suas causas, efeitos e formas de prevenção, a fim de auxiliar os profissionais da Odontologia na distinção das verdadeiras alterações da idade daquelas relacionadas a patologias, para que possam estabelecer condutas terapêuticas adequadas. Assim, foram estudados a estrutura óssea, o sistema neuromuscular, a articulação temporomandibular, glândulas salivares, mucosa oral, o periodonto, o tecido conjuntivo, o epitélio juncional, o cemento, o osso alveolar, o dente (esmalte, dentina, polpa) e a formação de placa bacteriana nos indivíduos idosos. Observou-se que mais informações e pesquisas são necessárias, em função do conhecimento de conceitos atuais, para possibilitar firmar dados conclusivos e sólidos a respeito do envelhecimento do Aparelho Estomatognático

With the increase of the life expectation around the world, the number of elderly people has been enlarged proportionally, but it can’t be observed on health care conditions for these people. By virtue of the heterogeneity of physical, psychic and social conditions presented by this group, nor all the professionals are able to understand and solve problems related with ageing. In that way, this work has for objective to explain the consequent modifications of the aging in the main structures on physiologic and anatomical extent of the Stomatognathic’s System, associating their causes, effects and prevention forms, in order to aid the professionals in the distinction of the true alterations of the age of those related to pathologies, so that they can establish appropriate therapeutic conducts. Like this, the bone structure, the system neuromuscular, the temporomandibular joint, salivary glands, oral mucosa, the periodontium, the conjunctive tissue, the junctional epithelium, the cementum, the alveolar bone, the tooth (enamels, dentine, pulp) and the formation of bacterial plaque in the elderly people. It was observed that more information and researches are necessary in function on the current concepts, to make possible to firm conclusive and solids data regarding the ageing of Stomatognathic’s System

Influencia del tiempo de almacenamiento sobre la dureza y rugosidad de materiales para rebasados resilentes / Influence of storage time on the hardness and roughness of soft liners materials

Fundamento: Los materiales para rebasados resilentes de prótesis, presentan ciertas características clínicamente importantes que pueden alterarse con el tiempo de uso, entre ellas la dureza, y rugosidad. El objetivo de este estudio fue evaluar la influencia del almacenamiento sobre la dureza Shore A y rugosidad de cuatro materiales resilentes para rebasado. Materiales y método: Fueron utilizados 4 materiales resilentes: Dentuflex, Coe-Soft, Dentusoft y Dinabase, 3 temporales y un permanente; para cada material fueron confeccionadas 7 muestras. Se evaluó la dureza y rugosidad inicialmente, a los 30 y 90 días de almacenamiento en agua destilada a 35±2ºC. Los resultados fueron sometidos al análisis de varianza (ANOVA) y las medias comparadas por el Test de Tukey (p<0,05). Resultados: Dentuflex, Coe-Soft, Dentusoft y Dinabase presentaron los mayores valores medios iniciales de dureza, en este orden. Con respecto a la rugosidad, Dentuflex, Dentusoft, Coe-Soft y Dinabase presentaron los mayores valores medios iniciales. Después del periodo de almacenamiento se observó un aumento significativo de los valores de dureza en todos los materiales. El material Dentuflex presentó valores de rugosidad significativamente menores, mientras que los valores de los otros materiales aumentaron significativamente. Conclusión: El tiempo de almacenamiento influenció sobre la dureza y rugosidad todos los materiales

Statement of problem: Resilient soft liners materials have many important features that could be altered over time, like hardness and roughness. The aim of this study was to assess the influence of water storage on the hardness Shore A and roughness of four resilient soft liners materials. Materials and methods: Four materials were used: Dentuflex, Coe-Soft, Dentusoft and Dinabase, three temporary and one permanent material. For each material 7 specimens were made. The hardness and the roughness were evaluated in the initial period, after 30 and 90 days of distilled water storage at 35±2ºC. The results were submitted to analyses of variance (ANOVA) and the averages compared by Tukey's Test (p<0.05). Results: Dentuflex, Coe-Soft, Dentusoft and Dinabase displayed higher initial average of hardness values, whereas Dentuflex, Dentusoft, Coe-Soft and Dinabase higher initial average of roughness values. After water storage a significant increase in the hardness values in all materials was observed. Dentuflex material showed smaller roughness values, while the other materials increased significantly. Conclusion: Time storage influenced all the materials analyzed with respect to hardness and roughness