Bond strength of fiber posts after the application of erbium:yttrium-aluminum-garnet laser treatment and gaseous ozone to the root canal

The aim of the present study was to investigate the effects of antibacterial agents (erbium:yttrium-aluminum-garnet [Er:YAG] laser or gaseous ozone) intended to disinfect root canals on bond strengths of fiber posts compared with canals that were finally irrigated using chlorhexidine (CHX). One hundred forty-four human anterior teeth were divided into three groups (n = 48); root canal instrumentation was performed, and antimicrobial pretreatment was conducted as follows: control group: CHX, group 2: Er:YAG laser, and group 3: gaseous ozone. In all groups, fiber posts were inserted using Panavia F 2.0 (Kuraray, Osaka, Japan), Variolink II (lvoclar Vivadent, Schaan, Liechtenstein), RelyX Unicem (3M Espe; Seefeld, Germany), or Ketac Cem (3M Espe) (n = 12 each). Push-out bond strengths to root canal dentin were affected by the type of luting agent but not by the antimicrobial pretreatment regimen. However, significant interactions between the luting agent and pretreatment could be observed, and adhesion of the self-adhesive resin cement RelyX Unicem was significantly reduced after using gaseous ozone.