Access opening and root canal preparation of specimens
JapanWaveOne reciprocating
COLD, CAVITY, PULP STONES
Preoperative periapical radiograph was taken for each specimen to ensure absence of any kind of root canal calcifications, internal resorption or presence of pulp stones or accessory canals. Rose-head bur and Endo-Z(Komet Dental. Gebr. Brasseler GmbH & Co. KG Trophagener Weg 25.32657 Lemgo. Germany) were mounted on high-speed handpiece, respectively, for access cavity preparation. Root canal length determination was done by inserting number 10 k-file (MANI, INC., Tochigi-Ken, JapanWaveOne reciprocating single file(Maillefer-Dentsply, Ballaigues, Switzerland.) was used for mechanical preparation of root canals up to the full working length. The tip size was ISO 40 with an apical taper of 8% that reduced towards the coronal end. Regarding irrigation, 2.5% Sodium Hypochlorite irrigation solution using 30-gauge side-vented irrigation needle(SUNGO Certification Company Limited, RM101, Maple House, 118 High Street Purley, London, England.); after every instrument change to ensure the complete elimination of any dentinal debris which might cause blockage of the canals [Root canals were dried using #40 paper points until complete drying of the canals was achieved. Cold lateral condensation technique was followed to obturate all the canals using ISO #40 gutta-percha(Metabiomed Co. LTD, South Korea.) cone, ISO #30 gutta percha(Metabiomed Co. LTD, South Korea.) accessory cones and ADseal sealer(Metabiomed Co. LTD, South Korea.) to the full working length. Access cavities were then filled with Tetric N-ceram nanohybrid composite(Ivoclar Vivadent Dental Products, Liechtenstein, Germany.) temporarily to be stored in laboratory incubator at 37 °C and 100% relative humidity for at least 2 days; allowing the complete setting of endodontic sealer [