Effect of root canal irrigation with different cross-linking agents on root fracture resistance

The aim of this study was to investigate the effect of root canal irrigation with solutions containing chitosan nanoparticles, carboxymethyl chitosan, chitosan nanoparticles functionalized with rose bengal, and genipin on root fracture resistance. Chitosan nanoparticles were produced by ionic gelation of chitosan with tripolyphosphate (TPP) anions. Particle size was evaluated by measuring zeta potential. Chitosan nanoparticles were conjugated with rose bengal to prepare a chitosan nanoparticle solution. The crowns of 60 single-canal and single-rooted mandibular premolar teeth were separated from their roots. When the root canal preparation was completed, irrigation was performed with NaOCl and EDTA, and the teeth were randomly divided into 5 groups. No additional application was made to Group 1. Chitosan nanoparticle solution was applied to Group 2. Carboxymethyl chitosan was applied to Group 3. Rose Bengal functionalized chitosan nanoparticles were applied to Group 4. Genipin solution was applied to Group 5.Genipin solution was kept in the canal for 30 minutes while other solutions were applied for 1 minute. Rose Bengal was activated with a diode laser at a wavelength of 940 nm. Each sample was finally irrigated with distilled water, then the canal was filled and covered with polyvinyl siloxane impression material, and then embedded in acrylic resin, leaving 2 mm of the sample exposed. As a result of the breaking test with a breaking device at a constant increasing speed of 1 mm/min, no statistically significant result was found between the groups in terms of fracture resistance.