Edition V03N02 | Year 2013 | Editorial Original Article | Pages 24 to 29
Objective: The aim of this study was to (1) evaluate the tissue dissolution effect of sodium hypochlorite (NaOCl) at different concentrations on the apical portion of mesial root of human mandibular molars with isthmuses; and (2) evaluate the dissolution time of bovine pulp tissue in direct contact at different concentrations and volumes of NaOCl.
Methods: Histologic investigation was performed in thirty mesial roots of human mandibular molars that were instrumented using the Mtwo system and irrigated with 2.5% NaOCl or 5.25% NaOCl. Saline solution was used as control. Each sample was submitted to histologic processing and the images were analyzed using the ImageJ software. The percentage of area occupied by tissue was calculated by dividing the area of tissue by the canals area. Data were analyzed by means of the analysis of variance with Tukey test (P < 0.05). Dissolution time was analyzed by immersing bovine pulp tissue in different volumes of 2.5% and 5.25% NaOCl solution. Results: No significant difference was found between the NaOCl concentrations in the histological investigation. No substance was able to completely clean the isthmuses. Moreover, a higher dissolution rate for the bovine pulp tissue was found in NaOCl with a concentration of 5.25%, in addition to a shorter dissolution time for larger volumes. Conclusion: The NaOCl is effective for tissue dissolution when in direct contact, however, NaOCl solution, even in high concentrations, was not competent to dissolve remnants of pulp tissue in root isthmuses during endodontic treatment. Sodium hypochlorite, Dissolution, Anatomy,
Zaia AA, Silva EJNL, Gomes AC, Moreira DM. Can the sodium hypochlorite tissue dissolution ability during endodontic treatment re- ally be trusted? An in vitro and ex vivo study. Dental Press Endod. 2013 May- Aug;3(2):24-9.