RESUMO
This study evaluated in vitro the shear bond strength of a resin-based pit-and-fissure sealant (Fluroshield - F) associated with either an ethanol-based (Adper Single Bond 2 - SB) or an acetone-based (Prime & Bond - PB) adhesive system under conditions of oil contamination. Mesial and distal enamel surfaces from 30 sound third molars were randomly assigned to 2 groups (n=30): I - no oil contamination; II - oil contamination. Contamination (0.25 mL during 10 s) was performed after 37% phosphoric acid etching with an air/oil spray. The specimens were randomly assigned to subgroups, according to the bonding protocol adopted: subgroup A - F was applied to enamel without an intermediate bonding agent layer; In subgroups B and C, SB and PB, respectively, were applied, light-cured, and then F was applied and light-cured. Shear bond strength was tested at a crosshead speed of 0.5 mm/min in a universal testing machine. Means (+/- SD) in MPa were: IA-11.28 (+/-1.84); IIA-12.02 (+/-1.15); IB-9.73 (+/-2.38); IIB-9.62 (+/-2.29); IC-28.30 (+/-1.63); and IIC-25.50 (+/-1.91). It may be concluded that the oil contamination affected negatively the sealant bonding to enamel and the acetone-based adhesive system (PB) layer applied underneath the sealant was able to prevent its deleterious effects to adhesion.
Assuntos
Adesivos Dentinários/química , Cura Luminosa de Adesivos Dentários , Selantes de Fossas e Fissuras/química , Acetona/química , Condicionamento Ácido do Dente , Bis-Fenol A-Glicidil Metacrilato/química , Esmalte Dentário/ultraestrutura , Análise do Estresse Dentário/instrumentação , Contaminação de Medicamentos , Etanol/química , Humanos , Teste de Materiais , Óleos/química , Organofosfonatos/química , Ácidos Fosfóricos/química , Ácidos Polimetacrílicos/química , Poliuretanos/química , Resistência ao Cisalhamento , Solventes/química , Estresse Mecânico , Temperatura , Fatores de Tempo , Água/químicaRESUMO
This study evaluated in vitro the shear bond strength of a resin-based pit-and-fissure sealant (Fluroshield - F) associated with either an ethanol-based (Adper Single Bond 2 - SB) or an acetone-based (Prime & Bond - PB) adhesive system under conditions of oil contamination. Mesial and distal enamel surfaces from 30 sound third molars were randomly assigned to 2 groups (n=30): I - no oil contamination; II - oil contamination. Contamination (0.25 mL during 10 s) was performed after 37 percent phosphoric acid etching with an air/oil spray. The specimens were randomly assigned to subgroups, according to the bonding protocol adopted: subgroup A - F was applied to enamel without an intermediate bonding agent layer; In subgroups B and C, SB and PB, respectively, were applied, light-cured, and then F was applied and light-cured. Shear bond strength was tested at a crosshead speed of 0.5 mm/min in a universal testing machine. Means (± SD) in MPa were: IA-11.28 (±1.84); IIA-12.02 (±1.15); IB-9.73 (±2.38); IIB-9.62 (±2.29); IC-28.30 (±1.63); and IIC-25.50 (±1.91). It may be concluded that the oil contamination affected negatively the sealant bonding to enamel and the acetone-based adhesive system (PB) layer applied underneath the sealant was able to prevent its deleterious effects to adhesion.
Este estudo avaliou in vitro a resistência ao cisalhamento (RC) de um selante resinoso [Fluroshield (F); Dentsply/Caulk] em associação com um sistema adesivo com solvente a base de etanol [Adper Single Bond 2 (SB); 3M/ESPE] ou a base de acetona [Prime & Bond (PB); 3M/ESPE] após contaminação com óleo do esmalte. Superfícies mesiais e distais de esmalte de 30 terceiros molares hígidos foram aleatoriamente alocadas em 2 grupos (n=30): I - contaminação com óleo; II - sem contaminação. A contaminação foi realizada (0,25 mL;10 s) com um jato de ar/óleo após o condicionamento do esmalte com ácido fosfórico a 37 por cento. Os espécimes foram aleatoriamente alocados em subgrupos, de acordo com a técnica adesiva empregada: A - F foi aplicado sobre o esmalte condicionado sem sistema adesivo; B - SB + F; C - PB + F. RC foi testada em uma máquina universal de ensaios (0,5 mm/min; 50 kgf) e os dados analisados por ANOVA e t-teste (α=0,01). As médias de RC em MPa foram: IA-11,28 (±1,84); IIA-12,02(±1,15); IB-9,73 (±2,38); IIB-9,62 (±2,29); IC-28,30 (±1.63); e IIC-25,50 (±1,91). Conclui-se que a contaminação com o óleo afetou a adesão do selante resinoso ao esmalte e o sistema adesivo com solvente a base de acetona (Prime & Bond) aplicado sob o selante foi capaz de impedir os efeitos deletérios da contaminação com óleo.
