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Study of abrasive resistance of composites for dental restoration by ball-cratering

Antunes, P. Vale; Ramalho, A.
Fonte: Universidade de Coimbra Publicador: Universidade de Coimbra
Tipo: Artigo de Revista Científica Formato: aplication/PDF
ENG
Relevância na Pesquisa
56.46%
Two-body abrasion occurs in the mouth whenever there is tooth-to-tooth contact. This is what most dentists call attrition. Abrasive wear may also occur when there is an abrasive slurry interposed between two surfaces, such that the two solid surfaces are not actually in contact, this is called three-body abrasion, with food acting as the abrasive agent, and occurs in the mouth during mastication. Abrasion is the key physiological wear mechanism that is present in dental materials during normal masticatory function. The two main categories of restoration materials are dental amalgam and composite restorative material. Although amalgam has excellent mechanical properties, it also has certain limitations and disadvantages. The main negative factors for amalgam are: aesthetic factor, toxicity of mercury, weak adhesion to healthy dental tissue, duration of restoration, corrosion and feeble resistance to fracture.; http://www.sciencedirect.com/science/article/B6V5B-48DXVSV-9/1/89cbc08def34c844243d168488b3bf18

Desgaste abrasivo da resina composta Filtek Z250 (4 diferentes cores, fotopolimerizadas por 3 diferentes tempos), através do método do disco retificado; Abrasive wear of Filtek Z250 composite resin (4 different colors, light-cured by 3 different times) through the retified disc method.

Freitas, Márcia Furtado Antunes de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Publicado em 24/05/2007 PT
Relevância na Pesquisa
56.19%
O objetivo neste trabalho foi avaliar a influência da variação do tempo de fotopolimerização para diferentes cores (I, B1, B3 e C4) de uma resina composta (FiltekTM Z250, da 3M ESPE), sobre a taxa de desgaste abrasivo através do método do disco retificado. Cada espécime de resina composta fotopolimerizada estava contido numa cavidade semicircular localizada na periferia de um disco constituído por polimetilmetacrilato (PMMA), denominado disco estático, sendo que a superfície curva da resina no disco sofria desgaste por um rebolo de porcelana, denominado tecnicamente de disco dinâmico, sob carga padronizada e velocidade controlada, criando no espécime uma cavidade de aspecto semicircular. O deslocamento vertical do disco estático, ao ser desgastado, era detectado por um palpador, o qual transferia estes dados a um computador e criava os arquivos de desgaste, em função do tempo. Os dados obtidos foram tratados estatisticamente. Pôde-se concluir que 1) a resistência à abrasão do PMMA foi a maior de todas e 2) a resina de cor C4, a mais resistente de todas.; The aim at this study was estimate the influence of light-curing time variation of different colors (I, B1, B3 and C4) of composite resin (FiltekTM Z250, 3M ESPE)...

Avaliação clínica e laboratorial de resina composta em função da fotoativação com diferentes fontes de luz e densidades de potência; Clinical and laboratorial evaluation of resin composite light-cured with different curing units and power densities

Benetti, Ana Raquel
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 27/07/2007 PT
Relevância na Pesquisa
46.19%
O objetivo deste estudo foi avaliar o desempenho clínico e laboratorial de uma resina composta, considerando diferentes fontes de luz e densidades de potência, mantendo-se padronizada a densidade total de energia. O grau de conversão da resina composta foi determinado através de espectroscopia por transformada de Fourier. O grau de amolecimento em etanol foi obtido pela determinação da dureza Wallace, antes e após o armazenamento da resina composta em etanol a 75%. O desgaste foi mensurado por dois métodos: o teste da ACTA e o teste de escovação simulada. Paralelamente, investigou-se o desempenho clínico de restaurações de resina composta em dentes posteriores, submetidas aos mesmos protocolos de fotoativação. Restaurações de classe I de resina composta foram confeccionadas e fotoativadas por lâmpada de quartzo-tungstênio ou diodo emissor de luz a 300 mW/cm2, durante 40 segundos, ou a 600 mW/cm2, durante 20 segundos. As restaurações foram avaliadas, imediatamente e após 6 e 12 meses, por dois examinadores calibrados, de acordo com os critérios modificados de Ryge. Os dados laboratoriais foram submetidos à análise de variância a dois critérios e teste de comparações múltiplas de Newman-Keuls, ou ao teste t-pareado. Os dados clínicos foram analisados pelos testes Kappa...

Desgaste abrasivo de uma resina composta, através de três diferentes métodos (disco retificado, escovação e nanodurômetro); Abrasive wear of a composite resin, using three different methods (ground disc, toothbrushing and nanodurometer)

Freitas, Márcia Furtado Antunes de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 16/09/2011 PT
Relevância na Pesquisa
56.27%
Neste estudo, foi avaliada a resistência ao desgaste abrasivo de uma resina composta, através de três diferentes métodos: do disco retificado, por escovação e do nanodurômetro. Nos dois primeiros métodos, foram utilizados 20 espécimes da resina Filtek Z250 (10 da cor Incisal e 10 da cor C4, ambos fotopolimerizados por 30 segundos cada) e 10 de polimetilmetacrilato (PMMA), atuando estes últimos como padrão de referência. Para os ensaios com o nanodurômetro, foi utilizado apenas um espécime de cada cor, assim como um único de PMMA, em cujas superfícies planas foram efetuadas sete medições, o que foi considerado equivalente a sete espécimes. No método do disco retificado, cada espécime de resina composta era confeccionado diretamente numa cavidade semicircular, localizada na periferia de um disco-suporte; os espécimes de PMMA consistiam em discos constituídos exclusivamente por este material; o desgaste de cada espécime era promovido por um disco de porcelana e seu conseqüente deslocamento era detectado por um palpador; assim, a taxa de desgaste era estabelecida, expressa em milímetros cúbicos por newton por segundo (mm3/N.s). No método de escovação, cada espécime cilíndrico ficava preso numa placa metálica...

Comparação dos valores de desgaste abrasivo e de microdureza de 13 resinas compostas usadas em odontologia através do método do disco retificado

Bianchi, Eduardo C.; Aguiar, Paulo Roberto de; Alves, Manoel C. S.; Freitas, César A. de; Rodrigues, Ana R.; Carvalho Jr., Oscar B. de
Fonte: Associação Brasileira de Polímeros Publicador: Associação Brasileira de Polímeros
Tipo: Artigo de Revista Científica Formato: 130-136
POR
Relevância na Pesquisa
46.4%
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP); Atualmente tem-se buscado simplificar a tarefa de caracterização da vida útil de restaurações dentárias realizadas por resinas compostas através de métodos laboratoriais, que são mais rápidos e não sofrem influência de variáveis pessoais inerentes às análises clínicas. Com este propósito, este trabalho apresenta uma nova metodologia de ensaio laboratorial para a avaliação do desgaste abrasivo de resinas compostas através do método do disco retificado. Realizaram-se ensaios de resistência ao desgaste abrasivo com 13 resinas compostas odontológicas e buscou-se analisar o comportamento da resistência ao desgaste abrasivo em relação à microdureza dessas resinas. Com a análise dos resultados concluiu-se que o método de discos retificados é eficiente para a obtenção da resistência ao desgaste abrasivo. Notou-se também ser extremamente pequeno o nível de correlação entre microdureza e desgaste abrasivo o que indica que cada resina composta tem características próprias e que o desgaste é dependente também de outros fatores.; It is now commonplace to search for methods to assess the useful lifetime of dental restorations made of resins...

Clinical evaluation of two packable resin-based composite restorations: A three-year report

Torres, Carlos Rocha Gomes; Barges, Alessandra Buhler; Goncalves, Sergio Eduardo Paiva; Pucci, Cesar Rogerio; De Araujo, Maria Amelia Maximo; Barcellos, Daphne Camara
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 338-343
ENG
Relevância na Pesquisa
36.25%
This randomized clinical trial sought to evaluate the performance of two packable composites over a period of 36 months. A total of 39 Class I and II restorations were placed in the permanent teeth of 20 patients. Using United States Public Health Services criteria, two investigators evaluated the restorations immediately after placement and again after 12 and 36 months, examining color match, marginal discoloration, marginal integrity, recurrent caries, proximal contact, anatomical shape, surface texture, and postoperative sensitivity. It was concluded that the packable composites evaluated showed satisfactory clinical performance after three years.

Desgaste e rugosidade superficial de um cimento de ionômero de vidro nanoparticulado

Scheffel, Débora Lopes Salles; Ricci, Hérica Adad; Panariello, Beatriz Helena Dias; Zuanon, Ângela Cristina Cilense; Hebling, Josimeri
Fonte: Universidade Estadual Paulista Publicador: Universidade Estadual Paulista
Tipo: Artigo de Revista Científica Formato: 430-435
POR
Relevância na Pesquisa
46.37%
To compare the abrasion wear resistance and superficial roughness of different glass ionomer cements used as restorative materials, focusing on a new nanoparticulate material. Material and Method: Three glass ionomer cements were evaluated: Ketac Molar, Ketac N100 and Vitremer (3M ESPE, St. Paul, MN, USA), as well as the Filtek Z350 (3M ESPE, St. Paul, MN, USA). For each material were fabricated circular specimens (n=12), respecting the handling mode specified by the manufacturer, which were polished with sandpaper disks of decreasing grit. The wear was determined by the amount of mass (M) lost after brushing (10,000 cycles) and the roughness (Ra) using a surface roughness tester. The difference between the Minitial and Mfinal (ΔM) as well as beroughness of aesthetic restorative materials: an in vitro comparison. SADJ. 2001; 56(7): 316-20. 11. Yip HK, Peng D, Smales RJ. Effects of APF gel on the physical structure of compomers and glass ionomer cements. Oper. Dent. 2001; 26(3): 231-8. 12. Ma T, Johnson GH, Gordon GE. Effects of chemical disinfectants on the surface characteristics and color of denture resins. J Prosthet Dent 1997; 77(2): 197-204. 13. International organization for standardization. Technical specification 14569-1. Dental Materials – guidance on testing of wear resistance – PART I: wear by tooth brushing. Switzerland: ISO; 1999. 14. Bollen CML...

Degradação de materiais restauradores resinosos e do esmalte deciduo e permanente em soluções simuladoras da dieta; Degradation of resin-based restorative materials and deciduous and permanent enamel in food-simulating media

Gisele Maria Correr Nolasco
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 22/02/2007 PT
Relevância na Pesquisa
46.52%
A cavidade bucal é considerada um ambiente agressivo onde a estrutura dentária e os materiais restauradores estão constantemente sujeitos a desafios térmicos, mecânicos e químicos. A associação destes fatores está diretamente relacionada à longevidade/estabilidade das restaurações, bem como à preservação da estrutura dentária. A exposição da estrutura dentária e dos materiais restauradores resinosos aos agentes da dieta pode causar erosão dental, amolecimento e aumento da rugosidade de restaurações resinosas, deixando-as mais susceptíveis ao desgaste. Dessa forma, os objetivos desta tese fundamentada em três capítulos foram: (1) avaliar o efeito do armazenamento em longo prazo em diferentes soluções simuladoras da dieta na rugosidade superficial de materiais restauradores resinosos; (2) avaliar o efeito da associação dos desafios erosivo e abrasivo no desgaste do esmalte decíduo e permanente; (3) avaliar o efeito da associação dos desafios corrosivo e abrasivo no desgaste de materiais restauradores resinosos. No capítulo 1, sessenta amostras de diferentes materiais restauradores (Filtek Z250, Esthet X, Filtek Flow, Dyract AP e Vitremer) foram armazenadas em 5 líquidos simuladores da dieta (água destilada...

Desgaste de materiais dentários de restauro direto; Wear of dental materials on direct restoration

Bentes, Ana Catarina Fernandes
Fonte: Universidade do Minho Publicador: Universidade do Minho
Tipo: Trabalho de Conclusão de Curso
Publicado em //2014 POR
Relevância na Pesquisa
36.55%
Dissertação de mestrado integrado em Engenharia Biomédica (área de especialização em Biomateriais, Reabilitação e Biomecânica); O desenvolvimento de resinas compostas como materiais de restauro dentário direto surgiu através da necessidade de materiais com características óticas semelhantes à estrutura dentária natural. Contudo, o desgaste destas resinas persiste como um dos principais problemas clínicos. Através de vários estudos, verificou-se que a resistência ao desgaste destes materiais depende fundamentalmente de aspetos relacionados com as partículas de carga, nomeadamente do seu tamanho e distribuição, assim como a sua percentagem volumétrica. O principal objetivo do presente trabalho consistiu na caracterização tribológica de resinas compostas de restauro dentário através da avaliação da sua resistência ao desgaste abrasivo e de deslizamento e pela identificação dos mecanismos de desgaste dominantes. Testes de compressão permitiram determinar a resistência à compressão das resinas compostas assim como o seu módulo de elasticidade. Foram efetuados testes de ball cratering utilizando uma emulsão à base de pasta dentífrica Colgate®Anti-tártaro mais branqueamento como abrasivo, com uma carga normal aplicada de 3 N e uma duração de 300 rotações. O estudo de caracterização tribológica foi complementado com testes de deslizamento linear alternativo na geometria esfera-placa em presença de saliva artificial à temperatura de 37 °. O deslizamento ocorreu contra alumina...

Wear and superficial roughness of glass ionomer cements used as sealants, after simulated toothbrushing

Rios,Daniela; Honório,Heitor Marques; Araújo,Paulo Amarante de; Machado,Maria Aparecida de Andrade Moreira
Fonte: Sociedade Brasileira de Pesquisa Odontológica e Faculdade de Odontologia da Universidade de São Paulo Publicador: Sociedade Brasileira de Pesquisa Odontológica e Faculdade de Odontologia da Universidade de São Paulo
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2002 EN
Relevância na Pesquisa
56.26%
The purpose of this study was to evaluate, in vitro, the properties (wear and roughness) of glass ionomer cements that could influence their indication as pit and fissure sealants. The utilized materials were Fuji Plus, Ketac-Molar and Vitremer (in two different proportions: 1:1 and ¼:1). The resin-based sealant Delton was used as control. By means of an electronic balance (precision of 10-4 g), wear was measured in function of weight loss after simulated toothbrushing. Superficial roughness was determined by means of a surface roughness-measuring apparatus. The results revealed that diluted Vitremer and Fuji Plus were less resistant to toothbrushing abrasion and had the greatest increase in superficial roughness.Although in clinical situations luting or diluted ionomer cements are often utilized as alternatives to resin-based sealants, the resultsof this study revealed that the properties of those cements are worse than those of restorative ionomers, whichpresented results similar to those of the evaluated resin sealant.

Dental wear caused by association between bruxism and gastroesophageal reflux disease: a rehabilitation report

Machado,Naila Aparecida de Godoi; Fonseca,Rodrigo Borges; Branco,Carolina Assaf; Barbosa,Gustavo Augusto Seabra; Fernandes Neto,Alfredo Júlio; Soares,Carlos José
Fonte: Faculdade De Odontologia De Bauru - USP Publicador: Faculdade De Odontologia De Bauru - USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2007 EN
Relevância na Pesquisa
56.43%
Bruxism is a pathological activity of the stomatognathic system that involves tooth grinding and clenching during parafunctional jaw movements. Clinical signs of bruxism are mostly related to dental wear and muscular and joint discomforts, but a large number of etiological factors can be listed, as local, systemic, psychological and hereditary factors. The association between bruxism, feeding and smoking habits and digestive disorders may lead to serious consequences to dental and related structures, involving dental alterations (wear, fractures and cracks), periodontal signs (gingival recession and tooth mobility) and muscle-joint sensivity, demanding a multidisciplinary treatment plan. This paper presents a case report in which bruxism associated with acid feeding, smoking habit and episodes of gastric reflow caused severe tooth wear and great muscular discomfort with daily headache episodes. From the diagnosis, a multidisciplinary treatment plan was established. The initial treatment approach consisted of medical follow up with counseling on diet and smoking habits and management of the gastric disorders. This was followed by the installation of an interocclusal acrylic device in centric relation of occlusion (CRO) for reestablishment of the occlusal stability...

Surface roughness and wear of resin cements after toothbrush abrasion

ISHIKIRIAMA,Sérgio Kiyoshi; ORDOÑÉZ-AGUILERA,Juan Fernando; MAENOSONO,Rafael Massunari; VOLÚ,Fernanda Lessa Amaral; MONDELLI,Rafael Francisco Lia
Fonte: Sociedade Brasileira de Pesquisa Odontológica - SBPqO Publicador: Sociedade Brasileira de Pesquisa Odontológica - SBPqO
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2015 EN
Relevância na Pesquisa
56.35%
Increased surface roughness and wear of resin cements may cause failure of indirect restorations. The aim of this study was to evaluate quantitatively the surface roughness change and the vertical wear of four resin cements subjected to mechanical toothbrushing abrasion. Ten rectangular specimens (15 × 5 × 4 mm) were fabricated according to manufacturer instructions for each group (n = 10): Nexus 3, Kerr (NX3); RelyX ARC, 3M ESPE (ARC); RelyX U100, 3M ESPE (U100); and Variolink II, Ivoclar/Vivadent (VL2). Initial roughness (Ra, µm) was obtained through 5 readings with a roughness meter. Specimens were then subjected to toothbrushing abrasion (100,000 cycles), and further evaluation was conducted for final roughness. Vertical wear (µm) was quantified by 3 readings of the real profile between control and brushed surfaces. Data were subjected to analysis of variance, followed by Tukey’s test (p < 0.05). The Pearson correlation test was performed between the surface roughness change and wear (p < 0.05). The mean values of initial/final roughness (Ra, µm)/wear (µm) were as follows: NX3 (0.078/0.127/23.175); ARC (0.086/0.246/20.263); U100 (0.296/0.589/16.952); and VL2 (0.313/0.512/22.876). Toothbrushing abrasion increased surface roughness and wear of all resin cements tested...

Two year clinical wear performance of two different polyacid modified resin composites in posterior permanent teeth

Lund, Rafael Guerra; Piva, Evandro; Moura, Fl??vio Renato Reis de; Demarco, Fl??vio Fernando; Lima, Jana??na de Oliveira; Cardoso, Paulo Eduardo Capel
Fonte: Universidade Estadual de Campinas Publicador: Universidade Estadual de Campinas
Tipo: Artigo de Revista Científica
EN_US
Relevância na Pesquisa
56.26%
Aim: The aim was to compare the clinical wear of two compomers (F2000; 3M/ESPE and Dyract AP; Dentsply) placed in occlusal cavities in permanent molars within a two-year follow-up period using an indirect method of evaluation. Methods: Twenty-one patients, whose treatment plans included Class I restorations, were selected. Each patient received two occlusal Class I restorations in permanent molars. One and 2 years after placement of the restorations, the 21 teeth restored with each material were submitted to wear evaluation. Polyvinylsiloxane impressions were taken and casts were made (baseline, 1 year and 2 years). The casts were classified by comparative evaluation using sets of 18 calibrated standard models (0 to 900 ??m), according to Leinfelder???s indirect method. Paired and unpaired t-tests were used for comparisons between the evaluations for the same material and between materials for each evaluation period, respectively. Results: The occlusal wear was higher after 2 years than after 1 year (p<0.001). The t-test demonstrated that the wear values, after 1 year, were similar for both compomers (F2000=17.6 ??m and Dyract AP=12.8 ??m). However, after 2 years, F2000 restorations (40.6 ??m) suffered significantly more wear (p<0.05) than Dyract AP restorations (29.8 ??m). Although compomers performed similarly after 1 year...

Radiation-induced root surface caries restored with glass-ionomer cement placed in conventional and ART cavity preparations: Results at two years

Hu, J.Y.; Chen, X.; Li, Y.Q.; Smales, R.; Yip, K.
Fonte: Australian Dental Assn Inc Publicador: Australian Dental Assn Inc
Tipo: Artigo de Revista Científica
Publicado em //2005 EN
Relevância na Pesquisa
36.32%
Background: There are no published studies comparing the clinical performances of more-viscous glass-ionomer cement (GIC) restorations when placed using conventional and atraumatic restorative treatment (ART) cavity preparation methods to restore root surface caries. Methods: One dentist used encapsulated Fuji IX GP and Ketac-Molar to restore 72 conventional and 74 ART cavity preparations for 15 patients who had received cervicofacial radiation therapy. Two assessors evaluated the restorations at six, 12, and 24 months for retention, marginal defects and surface wear, and recurrent caries. Results: After two years, the cumulative restoration successes were 65.2 per cent for the conventional and 66.2 per cent for the ART cavity preparations, without statistical or clinical significance (P>0.50). Restoration dislodgement accounted for 82.8 per cent and marginal defects for 17.2 per cent of all failures. There were no instances of unsatisfactory restoration wear or recurrent caries observed. Teeth with three or more restored cervical surfaces accounted for 79.3 per cent of all failures (P<0.0001). Conclusions: For root surface caries restored with GIC, the use of hand instruments only with the ART method was an equally effective alternative to conventional rotary instrumentation for cavity preparation. Larger restorations had higher failures...

Oral diagnosis and treatment planning: part 4. Non-carious tooth surface loss and assessment of risk

Kaidonis, J.
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: Artigo de Revista Científica
Publicado em //2012 EN
Relevância na Pesquisa
46.43%
Non-carious tooth surface loss or tooth wear is becoming an increasingly significant factor affecting the long-term health of the dentition. The adverse effects of tooth wear are becoming increasingly apparent both in young persons and, as more people retain their teeth, into old age. This situation challenges the preventive and restorative skills of dental practitioners.; J. A. Kaidonis

The effect of clinical polishing protocols on ceramic surface texture and wear rate of opposing enamel: a laboratory study.

Zaninovich, Michael
Fonte: Universidade de Adelaide Publicador: Universidade de Adelaide
Tipo: Tese de Doutorado
Publicado em //2014
Relevância na Pesquisa
36.33%
There has been a significant increase in the delivery of all ceramic restorations especially with the global explosion of CAD CAM technology. Frequently, the ceramic restorations require refinements to the surfaces with abrasives prior to or after cementation. If adjustments are made to a glazed or non-glazed surface after cementation, only mechanical polishing is an option to restore the surface texture. Surface roughness of ceramic restorations influences the aesthetics, functional and biological parameters of the restoration [1, 2]. A relatively rough surface can negatively influence the strength [3, 4] and longevity of a restoration [5, 6], increase friction [7] and rate of wear of the restoration [8] and opposing tooth structure [9], promote gingival inflammation [10], adverse soft tissue reactions [11], and the accumulation of stains and plaque on the surface [12-14]. Recent low fusing ceramics have properties which improve the surface characteristics and allows a relatively smoother surface to be achieved either by glazing or polishing [15, 16]. The aim of this study is to increase the understanding of the surface characteristics produced from either glazing or polishing and what impact the surface texture produced from such finishing methods has on the wear rate of opposing enamel. Clinically this will assist with decision making regarding the most effective method to achieve an optimal ceramic surface finish.; Thesis (D.Clin.Dent.) -- University of Adelaide...

Wear of double crown systems: electroplated vs. casted female part

Bayer,Stefan; Kraus,Dominik; Keilig,Ludger; Gölz,Lina; Stark,Helmut; Enkling,Norbert
Fonte: Faculdade De Odontologia De Bauru - USP Publicador: Faculdade De Odontologia De Bauru - USP
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/06/2012 EN
Relevância na Pesquisa
56.35%
OBJECTIVES: The wear of telescopic crowns is a common problem often reducing the patient's satisfaction with the denture and resulting in a renewal of the denture. The study aims to compare the wear behavior of conical crowns using electroplated copings (group E ) with standard telescopic crowns with cast female parts (group C). MATERIAL AND METHODS: 10 conical crowns were milled for each group of a cast gold alloy. The specimen of group E had a conicity of 2º. The cast secondary crowns of group C had a 0º design. The electroplated coping was established by direct electroforming. An apparatus accomplishing 10,000 wear cycles performed the wear test. The retentive forces and the correlating distance during insertion and separation were measured. The wear test was separated in a start phase, an initial wear phase and the long term wear period. The retention force value and the force-distance integral of the first 0.33 mm of each cycle were calculated. RESULTS: The retentive forces were significantly higher for group E and the integrals were significantly lower for this group except the integral at cycle 10,000. The changes of retention force and integral did not differ significantly between both groups in all phases. The change of the integrals as well as the integral at the particular cycles showed higher interquartile distances for group C. CONCLUSIONS: Within the limitations of this study the tested conical crowns showed clinically acceptable retentive properties. The values reached a range comparable to retentive elements tested in recent literature. The values of group C showed higher ranges. The force measured for group E was significantly higher than for group C but the integrals showed an opposite tendency. The results indicate that an exclusive analysis of the force is not sufficient as the integral is not equivalent to the force although it describes the retentive property of the system in a better way than the force over a distance is described. Both systems seem to be suitable for clinical practice.

Wear of double crown systems: electroplated vs. casted female part

Bayer, Stefan; Kraus, Dominik; Keilig, Ludger; Gölz, Lina; Stark, Helmut; Enkling, Norbert
Fonte: Universidade de São Paulo. Faculdade de Odontologia de Bauru Publicador: Universidade de São Paulo. Faculdade de Odontologia de Bauru
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/06/2012 ENG
Relevância na Pesquisa
56.35%
OBJECTIVES: The wear of telescopic crowns is a common problem often reducing the patient's satisfaction with the denture and resulting in a renewal of the denture. The study aims to compare the wear behavior of conical crowns using electroplated copings (group E ) with standard telescopic crowns with cast female parts (group C). MATERIAL AND METHODS: 10 conical crowns were milled for each group of a cast gold alloy. The specimen of group E had a conicity of 2º. The cast secondary crowns of group C had a 0º design. The electroplated coping was established by direct electroforming. An apparatus accomplishing 10,000 wear cycles performed the wear test. The retentive forces and the correlating distance during insertion and separation were measured. The wear test was separated in a start phase, an initial wear phase and the long term wear period. The retention force value and the force-distance integral of the first 0.33 mm of each cycle were calculated. RESULTS: The retentive forces were significantly higher for group E and the integrals were significantly lower for this group except the integral at cycle 10,000. The changes of retention force and integral did not differ significantly between both groups in all phases. The change of the integrals as well as the integral at the particular cycles showed higher interquartile distances for group C. CONCLUSIONS: Within the limitations of this study the tested conical crowns showed clinically acceptable retentive properties. The values reached a range comparable to retentive elements tested in recent literature. The values of group C showed higher ranges. The force measured for group E was significantly higher than for group C but the integrals showed an opposite tendency. The results indicate that an exclusive analysis of the force is not sufficient as the integral is not equivalent to the force although it describes the retentive property of the system in a better way than the force over a distance is described. Both systems seem to be suitable for clinical practice.

Dental wear caused by association between bruxism and gastroesophageal reflux disease: a rehabilitation report

Machado, Naila Aparecida de Godoi; Fonseca, Rodrigo Borges; Branco, Carolina Assaf; Barbosa, Gustavo Augusto Seabra; Fernandes Neto, Alfredo Júlio; Soares, Carlos José
Fonte: Universidade de São Paulo. Faculdade de Odontologia de Bauru Publicador: Universidade de São Paulo. Faculdade de Odontologia de Bauru
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; ; Formato: application/pdf
Publicado em 01/08/2007 ENG
Relevância na Pesquisa
56.43%
Bruxism is a pathological activity of the stomatognathic system that involves tooth grinding and clenching during parafunctional jaw movements. Clinical signs of bruxism are mostly related to dental wear and muscular and joint discomforts, but a large number of etiological factors can be listed, as local, systemic, psychological and hereditary factors. The association between bruxism, feeding and smoking habits and digestive disorders may lead to serious consequences to dental and related structures, involving dental alterations (wear, fractures and cracks), periodontal signs (gingival recession and tooth mobility) and muscle-joint sensivity, demanding a multidisciplinary treatment plan. This paper presents a case report in which bruxism associated with acid feeding, smoking habit and episodes of gastric reflow caused severe tooth wear and great muscular discomfort with daily headache episodes. From the diagnosis, a multidisciplinary treatment plan was established. The initial treatment approach consisted of medical follow up with counseling on diet and smoking habits and management of the gastric disorders. This was followed by the installation of an interocclusal acrylic device in centric relation of occlusion (CRO) for reestablishment of the occlusal stability...

Desgaste e rugosidade superficial de cimentos de ionômero de vidro utilizados como selantes, após escovação simulada; Wear and superficial roughness of glass ionomer cements used as sealants, after simulated toothbrushing

Rios, Daniela; Honório, Heitor Marques; Araújo, Paulo Amarante de; Machado, Maria Aparecida de Andrade Moreira
Fonte: Universidade de São Paulo. Faculdade de Odontologia Publicador: Universidade de São Paulo. Faculdade de Odontologia
Tipo: info:eu-repo/semantics/article; info:eu-repo/semantics/publishedVersion; Artigo Avaliado pelos Pares Formato: application/pdf
Publicado em 01/12/2002 ENG
Relevância na Pesquisa
56.26%
The purpose of this study was to evaluate, in vitro, the properties (wear and roughness) of glass ionomer cements that could influence their indication as pit and fissure sealants. The utilized materials were Fuji Plus, Ketac-Molar and Vitremer (in two different proportions: 1:1 and ¼:1). The resin-based sealant Delton was used as control. By means of an electronic balance (precision of 10-4 g), wear was measured in function of weight loss after simulated toothbrushing. Superficial roughness was determined by means of a surface roughness-measuring apparatus. The results revealed that diluted Vitremer and Fuji Plus were less resistant to toothbrushing abrasion and had the greatest increase in superficial roughness.Although in clinical situations luting or diluted ionomer cements are often utilized as alternatives to resin-based sealants, the resultsof this study revealed that the properties of those cements are worse than those of restorative ionomers, whichpresented results similar to those of the evaluated resin sealant.; O presente estudo foi conduzido in vitro com o intuito de constatar as propriedades (desgaste e rugosidade) dos CIV, as quais influenciam na sua indicação como material selador de fossas e fissuras. Os materiais empregados foram Fuji Plus...