Magister Scientiae Dentium - MSc(Dent) / Statement of problem: Although bioceramic endodontic sealer cements offer various advantages over conventional zinc oxide-based and resin-based cements, questions have been raised about the ability to retreat root canals that have been sealed using these cements. Aims and Objectives: The aim of the study was to determine the retreatability of root canals sealed using a bioceramic calcium silicate-based sealer cement. The objectives were to determine the possibility of achieving working length and apical patency when obturation is done with the master GP placed at working length and when it is short by 3mm. The time it took to achieve these parameters when it was possible to achieve them was also determined. The role of XP Endo Finisher R, a supplementary retreatment file, in achieving working length and apical patency was also to be evaluated. However, this latter aspect was eliminated after the pilot study, when it was found not to have an effect in regaining working length and apical patency.