The rubber dam was placed on the tooth, the working field disinfected and new sterile instruments were taken. The canals were prepared using the balanced force technique into size 50 each with flexoreamers and NiTiflex K-files and filing with Hedstroem files. The canals were constantly irrigated with 1 % sodium hypochlorite. At the end of the preparation the canal was irrigated with 17 % neutral EDTA and dried with paper points. Calcium hydroxide was packed into the canal and the access cavity cleaned with ethanol. Cavit G and IRM were used as a temporary filling. Three weeks later new calcium hydroxide was packed into the canal and the tooth was sealed again with a temporary filling. The tooth had been symptomfree the whole time.

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