Einfluss verschiedener Spüllösungen auf den Haftverbund des Sealers Apexit Plus zum Wurzelkanaldentin

The failure of a root canal treatment has several causes, but it is not always certain which one is responsible. To carry out the endodontic treatment, there are numerous procedures and pharmaceuticals available. It includes shaping, disinfection with suitable irrigants and a hermetic seal. The material should provide good adhesion to both root canal dentin and core material as well [101]. The aim of this in vitro study was to investigate the influence of different irrigations on the bond strength of calciumsalicylate-based sealer Apexit Plus and the root canal dentin. In this study 60 extracted and intact roots were randomly split into five groups (n=12). Their length was reduced and every canal was prepared with the BioRaCe instruments at a working length of 8 mm until .02#60. Afterwards the groups were allocate to an irrigation: A = chlorhexidine digluconate (CHX) 2%, B = EDTA 16%, C =NaOCl 3%, D = citric acid 40%, E = aqua dest. After irrigating with their fluid, the samples were dried with paper points. Subsequently, the experimental spreaders were inserted with the sealer. The teeth were stored for 14 days in 100% humidity until the pullout tests took place, using an universal testing maschine. The maximum force until adhesive failure was determined at an experimental speed of 2 mm/min. Additionally, the fracture modes of the spreaders were evaluated. In combination with CHX (0,73MPa) and NaOCl (0,62 MPa) Apexit Plus led to the highest bond strength. After irrigation with EDTA there were the lowest values (0,21 MPa). It showed a significant influence between irrigation and bond strength (Kruskal-Wallis-Test p=0,034). Within these conditions of this study, Apexit Plus does not benefit from smearlayer removal by EDTA. On the contrary, it led to less bond strength. The calciumsalicylatebased sealer behaves oppositely to most other root canal sealers, which usually acquire better results under the removal of the smearlayer. Based on the results of this study with Apexit Plus, the single irrigation with EDTA is not recommendable. If there could be an improvement of bond strength when additionally using CHX, was not aim of the study and further research is required.