Adhesion-cohesion inter-phase among fiberglass posts, dual cement and dentine before irrigation with two disinfectant materials

Resumen

A great number of  fiber-glass post de-cementation cases after adhesion to root canal have been reported. The aim of the present study was to assess  effectiveness of two disinfectant materials: 5.25% sodium hypochlorite (NaCIO), and 2% Chlohexidine used as irrigation agents before cementation of fiberglass posts (FGP) in the process of adhesion-cohesion, using dual cement (DC). Thirty teeth, endodontically treated with previously sectioned clinical crowns, were prepared  to each receive   a FGP. Samples were divided into three groups  and different root canal irrigation techniques were used: 1.- 5.25% NaCIO, 2.-  2% Chlorhexidine, and 3.- Water. Samples were transversely sectioned  with diamond disc at the cervical third (CT) and at the middle third (MT), thus,  60 study samples were obtained. Observation and measurement  of  dual cement/dentin (DC/D) and dual cement/post (DC/P) were conducted with scanning electron microscope. These measurements were taken at MT and CT. Gaps present at the  DC/D and DC/P  on surfaces free of adhesion-cohesion were also measured. Data analysis revealed significant differences with respect to effectiveness  with adhesion percentages  in DC/D dentine  when using  5.25% NaCIO technique versus 2% Chlorhexidine and water techniques. There was no observed significant difference in mean adhesion percentages in CT and MT. 5.25% NaCIO irrigation technique proved to be the one causing less DC/D and CD/P interference. It showed higher adhesion percentage both in DC/D inter-phase and DC/P cohesion inter-phase.