Active application of liquid etching agent improves adhesion of fibre posts to intraradicular dentine

Aim To assess the effectiveness of an active application of liquid etching, compared with the standard gel formulation on smear layer removal from post space walls and push‐out bond strength of luted fibre posts. Methodology Human extracted teeth were collected and root filled. After post space preparation and cleaning with 10% ethylenediaminetetraacetic acid for 30 s, teeth were assigned to four groups (n = 11) according to etching procedure: (i) 37% phosphoric acid (H3PO4) gel; (ii) 37% H3PO4 liquid applied with an endodontic needle; (iii) 37% H3PO4 liquid applied with an Endovac; (iv) no etching procedure (control group). Three teeth per group were sectioned longitudinally and prepared for SEM examination to evaluate the presence of smear layer, debris, sealer/gutta‐percha remnants, and the number of open tubules. Eight teeth per group were bonded with an etch‐and‐rinse adhesive, and fibre posts were luted with a resin‐based cement. After cutting, specimens were prepared for a push‐out test. Data were analysed by anova and post hoc tests (P