The impact of different voxels and exposure parameters of CBCT for the assessment of external root resorptions: A phantom study.

This study aimed to compare the effectiveness of the different voxel sizes and imaging parameters of cone beam computed tomography (CBCT) on the determination of external root resorption (ERR). ERRs were created in coronal, middle and apical regions. Depths (0.62-0.73 mm) and diameters (0.68-0.81 mm) of ERRs were measured using a digital calliper. Images were obtained in 0.125, 0.2, 0.25, 0.3 and 0.4 mm3 voxel sizes and at different currents. Data were analysed using Friedman and Wilcoxon signed-rank tests at a level of P < 0.05. There was a difference between the parameters in determining the size of the ERR in coronal and middle regions (P < 0.05), but there was no difference in the apical region (P > 0.05). The change in current and exposure time did not make a difference in determining the dimensions of the ERRs (P > 0.05). Some voxel dimensions were more reliable in determining the depth and diameter of ERR in the coronal and middle region.

Assessment of toxicity and oxidative DNA damage of sodium hypochlorite, chitosan and propolis on fibroblast cells.

The objective of this study was to evaluate and compare the cytotoxicity and genotoxicity on human fibroblast cell lines of sodium hypochlorite (NaOCl), chitosan and propolis as root canal irrigating solutions. Human fibroblast cells were exposed to chitosan, propolis and NaOCl for 4 and 24 h. Cell viability was assessed by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide, and oxidative DNA damage was assessed by determination of 8-hydroxydeoxyguanosine (8-OHdG) level with an ELISA kit. The data of cell cytotoxicity were analysed statistically using a test of one-way analysis of variance at a significance level of p < 0.05. In the NaOCI group, the 8-OHdG level was higher than in the chitosan group, but there was no statistical difference when compared with the other groups (p < 0.05). It was determined that the irrigation solutions were cytotoxic, depending on the dose and time. NaOCl was the most toxic solution after both 4 and 24 h of exposure (p < 0.05). Chitosan and propolis may be alternatives to NaOCl for irrigation solutions, because they are both less toxic and produce less oxidative DNA damage.

Assessment of toxicity and oxidative DNA damage of sodium hypochlorite, chitosan and propolis on fibroblast cells

Abstract The objective of this study was to evaluate and compare the cytotoxicity and genotoxicity on human fibroblast cell lines of sodium hypochlorite (NaOCl), chitosan and propolis as root canal irrigating solutions. Human fibroblast cells were exposed to chitosan, propolis and NaOCl for 4 and 24 h. Cell viability was assessed by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide, and oxidative DNA damage was assessed by determination of 8-hydroxydeoxyguanosine (8-OHdG) level with an ELISA kit. The data of cell cytotoxicity were analysed statistically using a test of one-way analysis of variance at a significance level of p < 0.05. In the NaOCI group, the 8-OHdG level was higher than in the chitosan group, but there was no statistical difference when compared with the other groups (p < 0.05). It was determined that the irrigation solutions were cytotoxic, depending on the dose and time. NaOCl was the most toxic solution after both 4 and 24 h of exposure (p < 0.05). Chitosan and propolis may be alternatives to NaOCl for irrigation solutions, because they are both less toxic and produce less oxidative DNA damage.