Effect of different solutions used as final irrigant on dentin surface: roughness analysis

INTRODUCTION : The use of irrigators can create microstructural changes in the dentin surface, including changes in roughness. These changes may influence the bonding process of filling materials to dentin. OBJECTIVE: The aim of this study was to evaluate the effect of EDTA, sodium hypochlorite or chlorhexidine, as final irrigant, in the roughness of the dentin surface. MATERIAL AND METHOD: Distal root of 6 mandibular molars were used. The roots were flatted with the aid of sandpaper and segmented, totaling 18 samples. The initial analysis was performed by using Dektak profilometer. Five areas were scanned per sample. Then, the samples were irrigated with NaOCl to simulate the chemomechanical preparation and washed with distilled water. The segments were divided into six groups according to the final flush protocol: Distilled water, 5.25% NaOCl, 2% chlorhexidine, 17% EDTA, 17% EDTA+ 5.25% NaOCl, 17% EDTA+ 2% chlorhexidine. Once again, in each sample, five areas were scanned, totaling 15 scans per group. Data were statistically analyzed using Kruskal - Wallis and Mann -Whitney tests (p<0.05). RESULT: Significant changes in roughness were found only in the association of the chelating agent with NaOCl. CONCLUSION: The final irrigation protocols have different effects on surface roughness of dentin.