Nanoparticles modified bioceramic sealers on solubility, antimicrobial efficacy, pushout bond strength and marginal adaptation at apical-third of canal dentin.

Abstract

Objective: The present study investigates the solubility, antimicrobial potency, pushout bond strength (PBS), and marginal adaptation of sealer modified using various nanoparticles (NPs) (silver, chitosan, HapNPs) to the root dentin at the apical third.

Methods: Forty-four human premolars were prepared for root canal treatment via a chemical mechanical approach. The teeth included were subsequently distributed into four groups based on the type of modified and unmodified sealers. Group 1 bioceramic (BC) sealer (Control), Group 2 (AgNPs modified BC sealer), Group 3 (CHNPs modified BC sealer), and Group 4 (HApNPs modified BC sealer). Solubility was assessed by making five samples and measured via precision balance. Antimicrobial testing against E. faecalis was performed using the Agar diffusion test. The bond strength and failure modes were assessed utilizing a universal testing machine and stereomicroscope respectively. A pair of specimens from each cohort was fixed to an aluminum stub to assess marginal adaptation via SEM at the apical third. Data analysis was performed utilizing one way ANOVA and followed by Tukey's post hoc test (p < 0.05).

Results: Sealers-modified HApNPs exhibited the lowest solubility (3.884 ± 0.15%) and strongest PBS (9.63 ± 0.12 MPa). Group 1 (Control) demonstrated highest solubility rate (6.144 ± 0.39%) and weakest bond strength (6.50 ± 0.09 MPa). All the modified sealers exhibited the largest zone of inhibition with no significant difference. Whereas the unmodified BC sealer group presented the smallest zone of bacterial inhibition.

Conclusion: Marginal adaptation of sealers does not affect the bond strength outcomes achieved. The incorporation of silver, chitosan, and hydroxyapatite nanoparticles into BC root canal sealers resulted in reduced solubility, enhanced antibacterial efficacy, and improved PBS compared to unmodified BC canal sealers.