Evaluation of sealing ability of chemically softened gutta-percha technique

Introduction. Obturation of the root canal is the final phase of endodontic therapy and it is usually used to assess the quality of endodontic treatment. The objective of this study was to examine the quality of apical sealing of the root canal after application of chemically softened gutta-percha. Material and Methods. Thirty extracted single rooted and multi rooted teeth, divided into two groups according to the material for obturation, were used in the study. After root canal instrumentation using step-back technique, obturation was completed using chemically softened gutta-percha and AH Plus and Apexit paste. The effect of apical sealing was assessed regarding the type of material used for the obturation. After obturation, teeth were coated with two coats of varnish and immersed in 50% solution of silver nitrate for twelve hours, and then longitudinally cut using diamond disc. Linear dye penetration was observed using light microscope and twenty five times magnification. The apical leakage was calculated using the measuring scale, previously mounted on microscope lens. Results. The results showed that the average penetration of silver nitrate in single rooted teeth obturated with the AH Plus paste was 132.8 μm, while in teeth obturated with Apexit, it was 148.6 μm. The difference was not statistically significant. Apical leakage in multi rooted teeth obturated with softened gutta-percha and AH Plus paste was 117.3 μm while in teeth obturated with Apexit, it was 158.5 μm. The difference was statistically significant. Conclusion. The lowest dye penetration in the apical portion of the canal was observed in multi rooted teeth obturated with AH Plus paste and the highest penetration of silver nitrate was in multi rooted teeth obturated with Apexit paste.