Parameters that Affect in vitro Bonding of Glass-ionomer Liners to Dentin

Abstract

The purpose of this study was to evaluate the effects of two concentrations of poly (acrylic acid) (10 and 25%), three treatments (untreated, passive conditioning, and active conditioning), and two storage conditions (24 hours in 37 degrees C water and thermal cycling) on the in vitro tensile bond strength of three commercial glass-ionomer liners to human dentin. Bond strengths to untreated dentin after storage for 24 hours ranged from 19.0 to 21.7 kg/cm2 for Glasionomer Base Cement, Cement/Liner, and Ketac-Bond, but dropped to a range of 4.9 to 9.7 kg/cm2 after thermal cycling. Active conditioning with 10% acid resulted in bond strengths after 24-hour storage that ranged from 23.5 to 44.0 kg/cm2, compared with values from 21.7 to 38.0 kg/cm2 with active conditioning using 25% acid. Active conditioning with 10% acid resulted in bond strengths after thermal cycling that were in the range of 15.8 to 27.4 kg/cm2 and were 80 to 320 percent higher than values resulting from passive conditioning under these conditions. Active conditioning with 10% acid for 30 seconds produced a bond strength for Glasionomer Base Cement of 44.0 kg/cm2, compared with a bond strength of 28.7 kg/cm2 for a 10-second active conditioning. Qualitative analysis of scanning electron photomicrographs showed that dentin tubules were opened to a greater extent by active conditioning with 25% acid than by passive conditioning with 10% acid.

Salvaging a tooth with a deep palatogingival groove: an endo‐perio treatment – a case report

“…It is a very conservative approach for eliminating deep palatoradicular grooves. Conditioning of the groove removes the surface debris, increases the wettability and increases the bond strength of glass-ionomer cement (Powis et al 1982, Barakat & Yamaguchi 1988. Glass-ionomer cement (Fuji I) was used, since it has an antibacterial effect, chemical adhesion to the tooth structure and good sealing ability International Endodontic Journal, 40, 808-817, 2007 ª 2007 International Endodontic Journal (Maldonado et al 1978, Vermeersch et al 2005.…”

In Vitro Wear of Glass-Ionomer Containing Restorative Materials

“…Improving the adhesion of glass-ionomers to enamel and dentin substrates is best achieved with high molecular weight acids with multiple functional groups; low molecular weight acids undesirably dissolve mineral content and degrade chemical bonding potential 79 . The typical surface conditioning concentration employed is 10-20% polyacrylic acid for ten seconds but may slightly vary by manufacturer 80 . This is in contrast to dentin bonding with resin composites, where micromechanical attachment to enamel and conversion of the hydrophilic organic components of dentin to hydrophobic surfaces is the overall goal.…”

Avaliação da adaptação à dentina de vários agentes de proteção com ou sem sistemarestaurador adesivo, em função de diferentes tratamentos da superfície dentinária.

“…O segundo tratamento realizado sobre a superfície dentinária foi o condicionamento com o ácido poliacrílico 10%, considerado um ácido fraco 71 , porém capaz de dissolver a "smear layer" sem desobliterar as embocaduras dos túbulos dentinários 78 . Esse ácido age penetrando na dentina e os ínos hidrogênio deslocam os íons cálcio e fosfato para a superfície 73,74,78 , regularizando e alisando a superfície dentinária 4,73,102,124 chegando a remover as marcas dos instrumentos operatórios e sendo capaz de formar pontes de hidrogênio com a superfície dentinária 124 . Segundo MOUNT 73,74 o ácido poliacrílico foi capaz de diminuir a energia livre da superfície dentinária 78 .…”

“…Contudo, nas concentrações de 40% no período de 10s 6,64,121 , 15s 29,121 ; 30s 6 ; na concentração de 25% por um período de 10s foram capazes de desobliterar os túbulos dentinários 6,29,64,121,124 . A regularização e alisamento da superfície dentinária também foi observada 4,73,102,124 o que permitiu uma melhor adaptação por parte do cimento de ionômero de vidro 73,102,124 evitando a inclusão de bolhas de ar na interface dente/c.i.v., deslocando os íons cálcio e fosfato 73 e removendo as marcas dos instrumentos operatórios 124 , formando pontes de hidrogênio com a superfície dentinária 124 . PRATI et al 93 encontraram que o ácido poliacrílico a 10% aplicado por 10s removeu parcialmente a "smear layer" superficial deixando os túbulos obstruídos, não expondo as fibras colágenas.…”