Adhesion of glass-ionomer cement sealers to bovine dentin conditioned withintracanal medications

This in vitro study assessed the adherence of glass-ionomer cement (GIC) ro ot canal sealers to dentin conditioned by three endodontic intracanal medic ations. Three GIC sealers were used: (i) Ketac-Endo; (ii) KT-308, an experi mental GIC sealer; and (iii) ZUT, a combination of KT-308 and a silver-cont aining zeolite (0.2% by weight). Superficial dentin of 120 bovine incisor c rowns was used as a substrate. The dentin was irrigated with 2.6% NaOCl for 30 s and then blotted dry. One of the following conditioning media (n = 30 ) was maintained in contact with the dentin for 7 days: (i) Ca(OH), paste; (ii) chlorhexidine gluconate (CHX) liquid 0.12%; (iii) formocresol (FML) li quid; (iv) distilled water (dH(2)O) used as control. The GIC sealers were a pplied to the conditioned dentin, bench set for 90 min, stored in 100% humi dity at 37 degreesC for 48 h, then tested to failure for shear bond strengt h (MPa) in an Instron machine. In the ZUT specimens, the shear bond strengt h did not differ significantly among those conditioned with Ca(OH)(2), CHX, FML, and dH(2)O. For KT-308, the mean scores were significantly lower (p < 0.05) after conditioning with CHX than with dH(2)O. For Ketac-Endo, the me an scores were significantly lower after conditioning with Ca(OH)(2) and FM L than with dH(2)O (p < 0.05). Furthermore Ketac-Endo demonstrated signific antly lower (p < 0.05) shear bond strength than KT-308 or ZUT to the dentin conditioned with Ca(OH)(2) or FML. The results suggest that intracanal med ications differentially influence the adhesion of various GIC sealers to ro ot canal dentin.