Resumen de Influence of the Passive Evaporation of adhesive on the conductance of dentin
Cristian Bersezio, Sebastian Toledo, Claudia Letelier, Andrea Werner, Osmir Batista de Oliveira Jr., Ziyad Haidar, Javier Martin, Eduardo Fernández
ABSTRACT: Aim: Determine the influence of time of passive evaporation of the solvent in a universal adhesive on the hydraulic conductance and permeability of dentin in an ex vivo human model. Henceforth, 60 healthy non-occluding third molars, indicated for therapeutic extraction/removal, of informed and consented patients aged between 18 and 30 years, were used here in. First, extracted teeth were incorporated into epoxy resin blocks and then dentin disks (1mm +/- 0.1 mm thick) were prepared. Dentin was acid etched with 35% ortho-phosphoric acid for 15 seconds in order to remove the smear layer and obtain permeable dentin. Samples were then randomized and divided into 5 groups (n=12). A Single Bond Universal adhesive layer with different time of passive evaporation of the solvent was then applied: GC=10 seconds, G1=30 seconds, G2=60 seconds, G3=300 seconds and G4=50 minutes. Finally, the flow rate was measured using a diffusion chamber, a model previously proposed by Pashley et al. Results: The obtained hydraulic conductance averages were as follows: GC=0.00052, G1=0.00018, G2=0.00006, G3=0.00005, G4=0.00005 expressed in uL•cm-2•min-1cm•H2O-1. For comparisons between groups, ANOVA and post hoc Tukey (ρ<0.05) tests were applied, resulting in a statistically significant difference between the GC group and all experimental groups (ρ <0.05). An influence of solvent passive evaporation thereby reducing hydraulic conductance in the experimental groups, was detected.
