Push out bond strength and fracture resistance after obturation with a bioceramic root canal filling material

Abstract

This study aims to compare the push-out bond strength and fracture resistance exhibited by root fillings performed with BC sealer and BCC. Eighty freshly extracted human permanent single-rooted mandibular premolars were de-coronated at a length of 16 mm. All root canals were enlarged using the M3 pro Gold instrument till the finishing file (40/4). Irrigation was done by the use of 3ml 2.5% NaoCl for 30 seconds at each change of file with a total volume of 12 ml/canal. Final irrigation was done by saline. Specimens were randomly divided into:  Push out bond strength test samples Thirty roots were randomly assigned according to obturation material into three groups (n=10) • Group (1): BC sealer + BCC • Group (2): BC sealer + GP • Group (3): resin sealer + GP  fracture resistance test samples: Fifty roots were randomly assigned according to obturation material into five groups (n=10) • Group (1): BC sealer + BCC • Group (2): BC sealer + GP • Group (3): resin sealer + GP • Group (4): negative control (unprepared unfilled) • Group (5): positive control (prepared unfilled) All groups were kept in an incubator and allowed for the full set of the sealers for 7 days at 37 ◦C and 100% humidity.

 Samples preparation for the push-out bond strength test: Samples were sectioned perpendicular to the long axis of the root using a water-cooled diamond blade where three sections of 2 mm thickness were obtained from the coronal, middle, and apical thirds of each sample. Push-out testing Loading will be performed with the universal Instron testing machine at a crosshead speed of 0.5 mm min1 until debonding occurs. The force applied at debonding will be recorded.