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1.
J Prosthet Dent ; 108(6): 370-6, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23217469

RESUMO

STATEMENT OF PROBLEM: Although titanium presents attractive physical and mechanical properties, there is a need for improving the bond at the titanium/luting cement interface for the longevity of metal ceramic restorations. PURPOSE: The purpose of this study was to evaluate the effect of surface treatments on the shear bond strength (SBS) of resin-modified glass ionomer and resin cements to commercially pure titanium (CP Ti). MATERIAL AND METHODS: Two hundred and forty CP Ti cast disks (9.0 × 3.0 mm) were divided into 8 surface treatment groups (n=30): 1) 50 µm Al(2)O(3) particles; 2) 120 µm Al(2)O(3) particles; 3) 250 µm Al(2)O(3) particles; 4) 50 µm Al(2)O(3) particles + silane (RelyX Ceramic Primer); 5) 120 µm Al(2)O(3) particles + silane; 6) 250 µm Al(2)O(3) particles + silane; 7) 30 µm silica-modified Al(2)O(3) particles (Cojet Sand) + silane; and 8) 120 µm Al(2)O(3) particles, followed by 110 µm silica-modified Al(2)O(3) particles (Rocatec). The luting cements 1) RelyX Luting 2; 2) RelyX ARC; or 3) RelyX U100 were applied to the treated CP Ti surfaces (n=10). Shear bond strength (SBS) was tested after thermal cycling (5000 cycles, 5°C to 55°C). Data were analyzed by 2-way analysis of variance (ANOVA) and the Tukey HSD post hoc test (α=.05). Failure mode was determined with a stereomicroscope (×20). RESULTS: The surface treatments, cements, and their interaction significantly affected the SBS (P<.001). RelyX Luting 2 and RelyX U100 exhibited similar behavior for all surface treatments. For both cements, only the group abraded with 50 µm Al(2)O(3) particles had lower SBS than the other groups (P<.05). For RelyX ARC, regardless of silane application, abrasion with 50 µm Al(2)O(3) particles resulted in significantly lower SBS than abrasion with 120 µm and 250 µm particles, which exhibited statistically similar SBS values to each other. Rocatec + silane promoted the highest SBS for RelyX ARC. RelyX U100 presented the highest SBS mean values (P<.001). All groups showed a predominance of adhesive failure mode. CONCLUSIONS: The adhesive capability of RelyX Luting 2 and RelyX U100 on the SBS was decisive, while for RelyX ARC, mechanical and chemical factors were more influential.


Assuntos
Colagem Dentária , Materiais Dentários/química , Cimentos de Ionômeros de Vidro/química , Cimentos de Resina/química , Titânio/química , Óxido de Alumínio/química , Bis-Fenol A-Glicidil Metacrilato/química , Compostos Inorgânicos de Carbono/química , Resinas Compostas/química , Cimentos Dentários/química , Corrosão Dentária/métodos , Polimento Dentário/métodos , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Resistência ao Cisalhamento , Silanos/química , Compostos de Silício/química , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo , Água/química
2.
J Adhes Dent ; 14(5): 453-9, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22518384

RESUMO

PURPOSE: To evaluate the effect of surface treatments on the shear bond strength (SBS) of a resin cement to commercially pure titanium (CP Ti). MATERIALS AND METHODS: Two hundred cast CP Ti disks were divided into 5 groups (n = 40), which were treated with one of the following air-abrasion techniques: (1) 50-µm Al2O3 particles; (2) 120-µm Al2O3 particles; (3) 250-µm Al2O3 particles; (4) 30-µm silica-modified Al2O3 particles (Cojet Sand); (5) 50-µm Al2O3 particles followed by 110-µm silica-modified Al2O3 particles (Rocatec Plus). For each air-abrasion technique, the following additional surface treatments were used (n = 10): (1) none; (2) adhesive Adper Single Bond 2; (3) silane RelyX Ceramic Primer; (4) silane plus adhesive. RelyX ARC resin cement was bonded to CP Ti surfaces. All specimens were thermocycled (5,000 cycles) before being tested in shear mode. Data (MPa) were analyzed using two-way ANOVA and Tukey's test (α = 0.05). Failure mode was determined with a stereomicroscope (20X). RESULTS: The results revealed that the air-abrasion technique (p < 0.001), additional surface treatment (p < 0.001) and their interaction were significant (p < 0.001). Except for the 50-µm Al2O3 + adhesive group, 250-µm Al2O3 particles promoted significantly higher SBS than 50-µm Al2O3 particles (p < 0.001), while Rocatec Plus provided bond strengths that were similar to or higher than those of Cojet Sand. Of the additional surface treatments, the adhesive provided the best results in combination with the 3 air-abrasion techniques (50-µm, 120-µm, and 250-µm Al2O3), whereas in the groups abraded with silica-modified Al2O3 particles (Cojet Sand and Rocatec Plus), the best results were obtained with additional silane. The two combinations that promoted the highest SBS were 250-µm Al2O3 + adhesive and Rocatec Plus + silane. All groups showed 100% adhesive failure. CONCLUSION: The selection of the best additional surface treatment varied according to the air-abrasion technique. Particle size was the decisive factor in determining the bond strength when micromechanical retention was the only bonding mechanism. When both mechanisms were present, in addition to particle size, the material applied as the additional surface treatment also contributed to determining the bond strength.


Assuntos
Colagem Dentária , Corrosão Dentária/métodos , Materiais Dentários/química , Cimentos de Resina/química , Titânio/química , Adesividade , Óxido de Alumínio/química , Bis-Fenol A-Glicidil Metacrilato/química , Cimentos Dentários/química , Análise do Estresse Dentário/instrumentação , Humanos , Teste de Materiais , Metacrilatos/química , Tamanho da Partícula , Polietilenoglicóis/química , Ácidos Polimetacrílicos/química , Resistência ao Cisalhamento , Silanos/química , Dióxido de Silício/química , Estresse Mecânico , Propriedades de Superfície , Temperatura , Fatores de Tempo
3.
Oper Dent ; 37(3): 253-62, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22313272

RESUMO

This study evaluated the shear bond strength (SBS) and stability of commercially pure titanium (CP Ti)/repair material interfaces promoted by different repair systems. One hundred CP Ti cast discs were divided into five repair system groups: 1) Epricord (EP); 2) Bistite II DC (BT); 3) Cojet (CJ); 4) Scotchbond Multi-Purpose Plus (SB) (control group); and 5) Cojet Sand plus Scotchbond Multi-Purpose Plus (CJSB). The specimens were stored in distilled water for 24 hours at 37°C, thermal cycled (5000 cycles, 5°-55°C) and stored under the same conditions for either 24 hours or six months (n=10). SBS was tested and the data were analyzed by two-way analysis of variance (ANOVA) and Tukey test (α=.05). Failure mode was determined with a stereomicroscope (20×). The repair system, storage time, and their interaction significantly affected the SBS (p<0.001). At 24 hours, CJSB exhibited the highest SBS value, followed by CJ. At six months, these two groups had similar mean SBS (p>0.05) and higher means in comparison to the other groups. For both storage times, BT presented the lowest SBS, while the EP and SB groups did not differ significantly from one another (p>0.05). There were no significant differences in SBS between the storage times for the groups EP and CJ (p>0.05). The groups BT, SB, and CJSB showed 100% adhesive failure, irrespective of storage time. The CJSB group showed the highest SBS at both storage times. At six months, the CJ group exhibited a similar SBS mean value when compared to the CJSB group. Water storage adversely affected the groups BT, SB (control group), and CJSB. Considering SBS values, stability, and the failure mode simultaneously, the CJ group showed the best CP Ti repair performance.


Assuntos
Colagem Dentária , Reparação em Prótese Dentária , Titânio , Análise do Estresse Dentário , Teste de Materiais , Cimentos de Resina/química , Resistência ao Cisalhamento , Dióxido de Silício , Propriedades de Superfície , Água
4.
Araraquara; s.n; 2011. 126 p. ilus, tab.
Tese em Português | LILACS, BBO - Odontologia | ID: biblio-866375

RESUMO

O reparo de restaurações metalocerâmicas fraturadas é uma opção de tratamento que possibilita o aumento da longevidade da restauração, preservando a estrutura dental, além de ser uma alternativa rápida e de menor custo. Entretanto, o estabelecimento de uma união forte e estável entre material reparador e substrato da restauração fraturada é essencial para o sucesso do reparo. Levando-se em consideração a grande utilidade dos reparos quando corretamente indicados e a possibilidade de um aprimoramento dos mesmos com esses novos sistemas, conforme prometem os fabricantes, foi propósito deste estudo avaliar, em titânio comercialmente puro, a resistência ao cisalhamento de quatro sistemas comerciais de reparo para metalocerâmicas e da variação de um destes, bem como a durabilidade de união após armazenamento em água. Foram confeccionados discos (9 × 3 mm) em titânio comercialmente puro. Estes foram incluídos em anel de PVC com resina acrílica e suas superfícies regularizadas com lixas de carbeto de silício de diferentes granulações (120, 220 e 320) em politriz. Os espécimes receberam um dos seguintes tratamentos (n=10): 1) Epricord, 2) Bistite II DC, 3) Cojet, 4) Scotchbond Multi Uso Plus (grupo Controle), e 5) uma variação do grupo Controle, na qual foram empregadas partículas de sílica do sistema Cojet Sand em substituição às de óxido de alumínio. Os espécimes foram armazenados em água destilada a 37ºC por 24 horas, termociclados (5.000 ciclos - 5º e 55ºC) e, então, armazenados nas mesmas condições descritas anteriormente, por um período adicional de 24 horas ou 6 meses. O ensaio de cisalhamento foi realizado em máquina de ensaios Material Test System 810 com velocidade de 0,5 mm/minuto. O modo da fratura foi avaliado em lupa estereoscópica (30x). Às 24 horas, as médias de resistência (MPa) dos grupos de 1 a 5 foram respectivamente: 13,00 + 2,04c, 8,10 + 1,16d, 18,34 + 2,16b, 13,41 + 1,42c, e 22,73 + 1,42a . Aos 6 meses, foram: 11,20 + 1,26b , 4,79 + 0,38c , 7,36 + 1,91a, 10,11 + 1,29b, e 18,55 + 1,22a . O armazenamento em água afetou significativamente a resistência de união dos grupos 2, 4 e 5, reduzindo suas resistências. Às 24 horas, a resistência ao cisalhamento da combinação Scotchbond Multi Uso/Cojet Sand foi significativamente maior em relação aos demais grupos. Aos 6 meses, o sistema Cojet e a combinação Cojet Sand/ Scotchbond Multi Uso Plus foram estatisticamente superiores aos demais grupos e iguais entre si


Repair is a good alternative treatment that can increase clinical longevity of the failed restoration, preserving tooth structure, with the advantages of less chair time and lower cost. However, the clinical success of repair depends on establishing a strong and longterm durable bond between the repair material and the metal surface of the failed restoration. Considering the great benefit of intra-oral repairs and the possibility of improvement with the use of new available repair systems, the purpose of the present study was to evaluate shear bond strength of different repair systems to commercially pure titanium (CP Ti) and bond durability after long-term water storage. One-hundred disk specimens of cast CP Ti (9 × 3 mm) were embedded in a PVC ring and their bonding surfaces were smoothed with silicon carbide papers (120, 220, and 320 grit) using a polisher. Specimens were divided into 5 groups of 20, which received one of the following repair systems: 1) Epricord, 2) Bistite II DC 3) Cojet, 4) Scotchbond Multipurpose Plus (control Group), and 5) Cojet Sand plus Scotchbond Multipurpose Plus (variation of the control Group). The specimens were stored in distilled water for 24 hours at 37ºC, thermal cycled (5,000 cycles ­ 5º to 55ºC) and then stored in distilled water at 37o C for either 24 hours or 6 months. Shear bond tests were performed in a mechanical testing machine with a crosshead speed of 0.5 mm/minute. Each specimen was examined under a stereoscopic lens with ×30 magnification. At 24 hours, the mean values (MPa) for the groups 1 to 5 were respectively 13,00 + 2,04c , 8,10 + 1,16d, 18,34 +2,16b, 13,41 + 1,42c, e 22,73 + 1,42a. After 6 months, the mean (MPa) of each group was respectively 11,20 + 1,26b , 4,79 + 0,38c, 17,36 + 1,91a , 10,11 + 1,29b e 18,55 + 1,22a. Long-term water storage significantly affected groups 2, 4, 5, which showed a significant decrease of shear bond strength. At 24 hours, Cojet Sand/Scotchbond Multipurpose Plus showed the highest shear bond strength when compared to the other four groups. After 6 months, Cojet Sand/Scotchbond Multipurpose Plus and Cojet systems were not statistically different and were statistically superior to the other groups


Assuntos
Titânio , Ligas Metalo-Cerâmicas , Reparação em Prótese Dentária , Resistência ao Cisalhamento
5.
Braz Dent J ; 21(2): 111-6, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20640356

RESUMO

Investigation of the effectiveness of surface treatments that promote a strong bond strength of resin cements to metals can contribute significantly to the longevity of metal-ceramic restorations. This study evaluated the effect of surface treatments on the shear bond strength (SBS) of a resin cement to commercially pure titanium (CP Ti). Ninety cast CP Ti discs were divided into 3 groups (n=30), which received one of the following airborne-particle abrasion conditions: (1) 50 microm Al(2)O(3) particles; (2) 30 microm silica-modified Al(2)O(3) particles (Cojet Sand); (3) 110 microm silica-modified Al(2)O(3) particles (Rocatec). For each airborne-particle abrasion condition, the following post-airborne-particle abrasion treatments were used (n=10): (1) none; (2) adhesive Adper Single Bond 2; (3) silane RelyX Ceramic Primer. RelyX ARC resin cement was bonded to CP Ti surfaces. All specimens were thermally cycled before being tested in shear mode. Failure mode was determined. The best association was Rocatec plus silane. All groups showed 100% adhesive failure. There were combinations that promote higher SBS than the protocol recommended by the manufacturer of RelyX ARC.


Assuntos
Abrasão Dental por Ar/métodos , Colagem Dentária , Falha de Restauração Dentária , Cimentos de Resina/química , Titânio/química , Análise de Variância , Descolagem Dentária , Restauração Dentária Permanente/métodos , Análise do Estresse Dentário , Humanos , Tamanho da Partícula , Resistência ao Cisalhamento , Estatísticas não Paramétricas , Estresse Mecânico , Propriedades de Superfície
6.
Braz. dent. j ; Braz. dent. j;21(2): 111-116, 2010. ilus, tab
Artigo em Inglês | LILACS | ID: lil-551930

RESUMO

Investigation of the effectiveness of surface treatments that promote a strong bond strength of resin cements to metals can contribute significantly to the longevity of metal-ceramic restorations. This study evaluated the effect of surface treatments on the shear bond strength (SBS) of a resin cement to commercially pure titanium (CP Ti). Ninety cast CP Ti discs were divided into 3 groups (n=30), which received one of the following airborne-particle abrasion conditions: (1) 50 ?m Al2O3 particles; (2) 30 ?m silica-modified Al2O3 particles (Cojet Sand); (3) 110 ?m silica-modified Al2O3 particles (Rocatec). For each airborne-particle abrasion condition, the following post-airborne-particle abrasion treatments were used (n=10): (1) none; (2) adhesive Adper Single Bond 2; (3) silane RelyX Ceramic Primer. RelyX ARC resin cement was bonded to CP Ti surfaces. All specimens were thermally cycled before being tested in shear mode. Failure mode was determined. The best association was Rocatec plus silane. All groups showed 100 percent adhesive failure. There were combinations that promote higher SBS than the protocol recommended by the manufacturer of RelyX ARC.


A investigação da eficácia de tratamentos de superfície que promovem uma forte resistência de união de cimentos resinosos aos metais pode contribuir significantemente para a longevidade das restaurações metalocerâmicas. Este estudo avaliou o efeito de tratamentos de superfície na resistência ao cisalhamento da união de um cimento resinoso ao titânio comercialmente puro (Ti cp). Noventa discos foram fundidos em Ti cp e divididos em 3 grupos (n=30), os quais receberam uma das seguintes condições de jateamento: (1) partículas de Al2O3 de 50 ?m; (2) partículas de Al2O3 modificadas por sílica de 30 ?m (Cojet Sand); (3) partículas de Al2O3 modificadas por sílica de 110 ?m (Rocatec). Para cada condição de jateamento, os seguintes tratamentos pós-jateamento foram utilizados (n=10): (1) nenhum; (2) adesivo Adper Single Bond 2; (3) silano RelyX Ceramic Primer. O cimento resinoso RelyX ARC foi aplicado à superfície do Ti cp. Todos os espécimes foram termociclados antes do ensaio de cisalhamento. O modo de fratura também foi determinado. A melhor associação foi o Rocatec mais silano. Todos os grupos apresentaram 100 por cento de falha adesiva. Houve combinações que promoveram maior resistência ao cisalhamento da união que aquela recomendada pelo fabricante do RelyX ARC.


Assuntos
Humanos , Abrasão Dental por Ar/métodos , Colagem Dentária , Falha de Restauração Dentária , Cimentos de Resina/química , Titânio/química , Análise de Variância , Descolagem Dentária , Análise do Estresse Dentário , Restauração Dentária Permanente/métodos , Tamanho da Partícula , Resistência ao Cisalhamento , Estatísticas não Paramétricas , Estresse Mecânico , Propriedades de Superfície
7.
Rev. odontol. Univ. Cid. Sao Paulo ; 21(3)set.-dez. 2009. ilus
Artigo em Português | LILACS-Express | LILACS | ID: lil-553626

RESUMO

Repairing fractured metal-ceramic prosthesis is a treatment alternative that can increase the restoration longevity, preserve dental structure, and/or the integrity of implant components, besides being a simple, low-cost technique. However, clinicians often see restoration repair as a challenge because of the many doubts regarding the procedures required to obtain satisfactory results. Therefore, the motivation to write this article is the need to provide instructions for clinicians dealing with a situation involving fractured porcelain, presenting an intraoral repair technique that can be used in cases of a fractured ceramic veneer of a fixed partial prosthesis. The technique consisted in treating the remaining ceramic surface and applying a microhybrid composite resin following the steps of a protocol that, according to scientific evidence, has promoted high bond strength to porcelain, in addition to being cost effective.


O reparo de próteses metaloceramicas, quando a cerâmica encontra-se fraturada, e um tratamento alternativo que pode aumentar a longevidade dessas restaurações, preservar a estrutura dental ou a integridade de componentes protéticos sobre implantes, alem de ser uma técnica simples e de baixo custo. No entanto, essa técnica, geralmente, e vista como um desafio pelos cirurgiões-dentistas uma vez que não ha um protocolo clinico bem estabelecido para a obtenção de resultados satisfatórios. Assim sendo, o objetivo deste artigo e prover instruções para os clínicos lidarem com situações de fratura da cerâmica por meio da apresentação de um caso clinico, no qual uma técnica de reparo intra-oral indicada para essa situação foi empregada. Essa técnica consiste em tratar a superfície da cerâmica remanescente e aplicar uma resina composta microhibrida, seguindo os passos de um protocolo que, de acordo com evidencias cientificas, tem promovido alta resistência de união, alem de apresentar um baixo custo.

8.
Gen Dent ; 57(6): 644-51; quiz 652-3, 595, 680, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19906617

RESUMO

This study evaluated the shear bond strength of different repair systems to nickel-chromium (NiCr) alloy after storage in water for either 24 hours or six months. One hundred cylindrical specimens (3 mm thick x 9 mm diameter) were fabricated using an NiCr alloy and embedded in a PVC ring, where they received one of five bonding and resin composite repair treatments (n = 20): Clearfil SE Bond/Clearfil AP-X (Group 1), Bistite II DC/Palfique (Group 2), CoJet/Z100 (Group 3), Scotchbond Multi-Purpose Plus/Z100 (Group 4; reference group), and CoJet Sand plus Scotchbond Multi-Purpose Plus/Z100 (Group 5). The specimens were stored in distilled water for 24 hours at 37 degrees C, thermocycled for 1,000 cycles in two baths (at 5 degrees C and 55 degrees C) with a dwell time of 30 seconds for each bath, and stored in distilled water at 37 degrees C for either 24 hours or six months. At 24 hours, Group 3 presented the highest mean values (P < 0.001); at six months, Group 5 demonstrated the highest mean values (P < 0.001). At six months, Group 5 presented a significant increase in shear bond strength (P < 0.001), while Groups 1 and 3 showed a significant reduction (P < 0.001). There were no significant differences between the storage times for Group 2 (P = 0.064) or Group 4 (P = 0.490).


Assuntos
Ligas de Cromo , Colagem Dentária , Reparação em Prótese Dentária , Ligas Metalo-Cerâmicas , Cimentos de Resina , Análise do Estresse Dentário , Hidrólise , Teste de Materiais , Resistência ao Cisalhamento
9.
J Prosthet Dent ; 101(4): 262-8, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19328279

RESUMO

STATEMENT OF PROBLEM: A strong and durable bond between a metal framework and a resin-based luting agent is desired. Metal primers have been shown to be very effective on noble alloys. However, there is insufficient information about their effect on base metals. PURPOSE: The purpose of this study was to evaluate the effect of metal primers on the shear bond strength of resin cements to base metals. MATERIAL AND METHODS: A total of 160 cast commercially pure titanium (CP Ti) and NiCr alloy (VeraBond II) disks were embedded in a polyvinyl chloride ring, and their surfaces were smoothed with silicon carbide papers (320, 400, and 600 grit) and airborne-particle abraded with 50-mum aluminum oxide. Specimens of each metal were divided into 4 groups (n=20), which received one of the following luting techniques: (1) Panavia F, (2) Alloy Primer plus Panavia F, (3) Bistite II DC, or (4) Metaltite plus Bistite II DC. Forty minutes after preparation, all specimens were stored in distilled water at 37 degrees C for 24 hours and then thermal cycled (1000 cycles, 5-55 degrees C). After thermal cycling, the specimens were stored in 37 degrees C distilled water for an additional 24 hours or 6 months before being tested in shear mode. Data (MPa) were analyzed using 3-way ANOVA and the post hoc Tukey test (alpha=.05). Each specimen was examined under an optical microscope (x30), and the failure mode was classified as adhesive, cohesive, or a combination of these. RESULTS: The only significant difference between the Panavia F and Alloy Primer plus Panavia F groups occurred in the NiCr alloy at 24 hours, at which point Panavia F demonstrated superior bond strength compared to Alloy Primer plus Panavia F (P<.001). The Bistite II DC and Metaltite plus Bistite II DC groups were not significantly different. The Bistite II DC and Metaltite plus Bistite II DC groups demonstrated significantly lower bond strength to CP Ti (P<.001) than the Panavia F and Alloy Primer plus Panavia F groups, and significantly lower bond strength to NiCr alloy (P<.001) than Panavia F. The Panavia F (P<.01) and Alloy Primer plus Panavia F groups' bond strength to titanium presented a significant increase (P<.001) in shear bond strength at 6 months. In general, the groups exhibited higher shear bond strength to CP Ti than to NiCr alloy (P<.01). The failure mode was 100% adhesive for all groups. CONCLUSIONS: The metal primers did not promote an increase in adhesive bonding of resin cements to NiCr alloy and to CP Ti. Water storage had no adverse effect on the shear bond strength of the groups. The shear bond strengths to titanium were significantly higher than those to the NiCr alloy.


Assuntos
Coroas , Ligas Dentárias/química , Colagem Dentária/métodos , Cimentos de Resina/química , Análise de Variância , Ligas de Cromo/química , Análise do Estresse Dentário , Teste de Materiais , Metacrilatos/química , Resistência ao Cisalhamento , Estatísticas não Paramétricas , Tionas/química , Titânio/química
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