The use of Heliox plasma to improve the adhesion of a self-adhesive resin cement to NaOCl treated dentin

Abstract Objectives To evaluate the influence of Heliox plasma to improve the adhesion of self-adhesive resin cement to sodium hypochlorite (NaOCl) treated dentin, in comparison to antioxidant agents, for fiber post cementation. Material and Methods 88 bovine teeth were selected and were cut producing 7mm samples. 65 roots canals were enlarged and assigned to five groups (n=13) according to the treatments, for 1 minute, as follows: control (distilled water); NaOCl (immersed in 5.25% NaOCl for 20 minutes); plasma (after NaOCl immersion, premixed helium and oxygen plasma were applied); sodium thiosulfate (ST) and ascorbate (SA) (after NaOCl immersion, the samples were immersed in 5% ST or 10% SA, respectively). Fiberglass posts were cemented and submitted to the push-out bond strength (POBS) in 10 of 13 samples from each group. Three samples were analyzed by scanning electron microscopy (SEM). Flat dentin surfaces were obtained from the 23 remaining roots and used for measuring surface energy. Results POBS values were ranked as: SA>plasma>ST=control>NaOCl. The ascorbate and plasma groups showed some smear layer removal by SEM. Surface energy was ranked as: control<NaOCl=ST <SA<plasma. Heliox plasma and antioxidant agents restored the POBS of NaOCl-treated dentin. Conclusion The use of Heliox plasma or antioxidant agents for 1 minute improved the adhesion of fiberglass post to dentin using RelyX U200. Clinical Relevance Heliox plasma and antioxidant agents restored bond strength of treated dentin.