RESUMO
The purpose of this study was to determine the effect of accidental dentin primer contact with etched enamel on shear bond strength of composite resin to enamel. Four dentin bonding systems were included in this study: GLUMA Dentin Bond, Scotchbond, and Prisma Universal Bond 2 and 3. Eighty extracted human permanent anterior teeth were used and divided in eight test groups. The vestibular surfaces were ground and acid etched. For each dentin bonding system 10 samples were treated with dentin primer prior to placement of resin. Shear bond testing showed that enamel contact with dentin primer in the above two systems decreased the shear bond strength between composite and enamel by 31 to 44%.
Assuntos
Resinas Compostas , Colagem Dentária , Esmalte Dentário/efeitos dos fármacos , Adesivos Dentinários , Cimentos de Resina , Condicionamento Ácido do Dente , Adesivos Dentinários/química , Adesivos Dentinários/farmacologia , Glutaral/química , Glutaral/farmacologia , Humanos , Teste de Materiais , Ácidos Polimetacrílicos/química , Ácidos Polimetacrílicos/farmacologia , Propriedades de Superfície/efeitos dos fármacos , Resistência à TraçãoRESUMO
The objective of this study was to evaluate the effect of different bonding systems on teh microleakage at the amalgam/composite interface. The microleakage at the amalgam/composite resin interface was evaluated with a quantitative dye penetration method. Amalgam cylinders were made and a 2 mm composite base was added after the application of five different bonding systems to the roughened interface of the amalgam cylinders. The cylinders were filled with an exact volume of 0.05% fuchsin solution, and the total weight of the sample was measured. The cylinders were placed on a filter paper with the composite base down and evaluated for leakage after 1, 3, 6, and 24 hours. Weight loss and coloring of the filter paper represented microleakage. The results indicated that the application of Prisma Universal Bond 2 adhesive, Cover Up II, or Amalgambond (groups E, F, and G) reduced the amount of microleakage significantly as compared to the groups in which no adhesive system, 3M Porcelain Repair Kit (with and without acid etching of the amalgam surface), or Prisma Universal Bond 2 primer and adhesive (groups A, B, C or D) was applied.
Assuntos
Resinas Compostas , Amálgama Dentário , Colagem Dentária , Cimentos Dentários , Infiltração Dentária/prevenção & controle , Adesivos Dentinários , Metacrilatos , Silanos , Fatores de TempoRESUMO
This study evaluated the tensile strength of repaired high-copper amalgams and analyzed the different treatments of the amalgam interface prior to repair. One hundred specimens were divided into 10 groups: group 1 was left intact and was considered as the control group. In groups 2 through 8, the specimens were sectioned into halves after 10 days and were reconstructed with new amalgam. Groups 9 and 10 were condensed with time intervals of 15 minutes and all specimens were subjected to tensile loads in a Universal Testing Machine. The tensile strengths at the junction between old and new amalgam ranged between 50% to 79% of those of the control group and verified that the same type of amalgam and uncontaminated interfaces had higher strengths. The results also suggested that if an amalgam repair is anticipated, additional retention is critical to the longevity of the restoration.
Assuntos
Cobre/química , Amálgama Dentário/química , Colagem Dentária , Restauração Dentária Permanente , Análise do Estresse Dentário , Teste de Materiais , Propriedades de Superfície , Resistência à TraçãoRESUMO
The shear bond strengths of intact high-copper spherical and admixed amalgams were compared with repaired high-copper spherical and admixed amalgam specimens with and without the use of an adhesive system (Amalgambond). In the spherical group the shear bond strength of the repaired specimens was found to be 55 and 53.2% of the intact specimens without and with the use of the adhesive system. After thermocycling those percentages were 48.5 and 43. In the admixed groups those percentages were 39, 36.5, 34.5, and 35.2 respectively. It was found that the application of Amalgambond did not significantly increase the strength of the repaired amalgam. Thermocycling only had a significantly adverse effect on the repair strength in the admixed group repaired without an adhesive system.
Assuntos
Ligas Dentárias , Amálgama Dentário , Colagem Dentária , Metacrilatos , Cobre , Temperatura Alta , Resistência à TraçãoRESUMO
The shear bond strength between amalgam and composite resin with and without the use of adhesive systems was evaluated. It was found that the application of Cover-Up II or Prisma Universal Bond prior to placement of composite resin enhanced the shear bond strength between amalgam and composite resin more than five times; and a shear strength of 4.34 and 4.30 MPa was measured respectively. Acid-etching of the roughened amalgam surface prior to application of Prisma Universal Bond decreased the bond strength by nearly 45%.
Assuntos
Resinas Compostas , Amálgama Dentário , Colagem Dentária/métodos , Adesivos Dentinários , Adesividade , Adesivos , Metacrilatos , Resistência à TraçãoRESUMO
A new dye-diffusion test method was utilized to evaluate the microleakage between amalgam and composite resin. An amalgam cylinder was made to which a base of composite was added. The effects of several factors upon the microleakage were investigated. The test results indicated less microleakage when bonding agent was applied directly to the roughened amalgam prior to placement of composite resin. The most microleakage was found when roughened amalgam surface was acid-etched before placement of bonding agent and composite resin.
