To investigate the impact of different post-space disinfectants Nd: YAP laser, Radachlorin, and calcium oxide nanoparticles on smear layer removal efficacy and bond durability of PEEK posts to canal dentin.

AIMS: Effect of post-space disinfectants Nd: YAP laser, Radachlorin® photosensitizer, and calcium oxide nanoparticles (CaONPs) on the smear layer (SL) removal efficacy and push out bond strength (PBS) of polyetheretherketone (PEEK) post to root dentin.

METHODOLOGY: Forty-four human premolars possessing a single root having a complete apex were acquired and endodontically treated. Gates glidden drills were used to prepare the post space. The teeth were then randomly allocated into 4 groups according to the disinfectant used (n = 11) Group 1: 2.5 % NaOCl+17 % EDTA, Group 2: Nd: YAP laser+17 % EDTA, Group 3: Radachlorin+17 % EDTA and Group 4: CaONPs+17 % EDTA. A single sample from each respective group was carefully sectioned and observed under SEM magnification for SL removal(n = 1). PEEK post was cemented using resin cement followed by artificial aging (n = 10). PBS testing was conducted using a universal testing machine and failure mode was analyzed under a stereomicroscope. A one-way analysis of variance, accompanied by post hoc analysis was applied for statistical assessment of data (p<0.05) RESULTS: The specimens from Group 1 (2.5 % NaOCl+EDTA) (1.65±0.02) showed the highest efficacy in eliminating SL from the canal as well as the highest PBS. Conversely, Group 3 (Radachlorin+EDTA) samples revealed the least efficacy in the removal of SL and bond integrity of PEEK post.

CONCLUSION: Sodium hypochlorite followed by ethylenediamine-tetra acetic acid displayed better performance than all the other tested groups in SL removal and bond integrity outcomes when PEEK post was bonded to the canal dentin.