[In vitro cytotoxicity of different self-etching dental adhesive systems]

The study evaluated the cytotoxicity of five self-etching dentin adhesive systems applied on dentin specimens of different thicknesses. The test materials (A: Adper Prompt-L-Pop, B: Xeno II, C: Clearfil SE Bond, D: One up Bond F, E: Resulcin Aqua Prime & Monobond) and a positive control (35% H202) were applied on 1.0, 1.5 and 2.5 mm thick bovine dentin specimens (each subgroup n = 5) in a dentin barrier test device. The experiments were performed with perfusion (2 ml/h) of the pulpal part of the chamber. The eluates were obtained before (baseline) and 15, 30, 45, 60 and 120 min after application of the adhesives and pipetted onto L-929 fibroblasts. Cytotoxicity of the materials was determined in relation to the baseline value using the MTT assay and statistical analysis was performed by ANOVA. After 15 min perfusion, test materials B-E applied on 1.0 mm and B and E applied on 1.5 mm dentin specimens exhibited cytotoxic potential. However, after 30 min perfusion none of the adhesives showed any toxicity. Cytotoxicity decreased with increasing thickness of the dentin slices and was lower for Adper Prompt-L-Pop compared to adhesives B-E. Self-etching adhesive systems might exhibit cytotoxic potential when applied on dentin of less than 1.5 mm thickness. However, cytotoxicity of the materials decreased with increasing dentin thickness and increasing duration of perfusion.