Sodium hypochlorite with reduced surface tension does not improve in situ pulp tissue dissolution

Area of Science:

• Endodontics
• Dental Materials Science

Background:

• Sodium hypochlorite (NaOCl) is a common irrigant in endodontics, used for dissolving necrotic tissue.
• NaOCl solutions with reduced surface tension are marketed to enhance tissue dissolution efficacy.
• The study investigates claims that lowered surface tension improves NaOCl's tissue dissolving capability.

Purpose of the Study:

• To compare the efficacy of a reduced surface tension NaOCl solution against a conventional NaOCl solution in dissolving vital pulp tissue.
• To test the null hypothesis that there is no difference in tissue dissolution between the two types of NaOCl solutions in oval root canals.

Main Methods:

• A comparative study using 44 extracted teeth, paired based on anatomy.
• Chemomechanical preparation followed by irrigation with either 5.25% NaOCl with reduced surface tension or 5.25% conventional NaOCl.
• Histological assessment of the percentage of remaining pulp tissue (PRPT) in cross-sections.

Main Results:

• The level of the root cross-section significantly influenced PRPT (P < .05).
• No significant difference in PRPT was observed between the reduced surface tension NaOCl and conventional NaOCl groups (P > .05).
• A significant inverse correlation between cross-section level and PRPT indicates less tissue dissolution closer to the apex.

Conclusions:

• Reduced surface tension NaOCl does not offer superior vital pulp tissue dissolution in oval root canals compared to conventional NaOCl.
• Pulp tissue dissolution efficiency decreases with proximity to the root apex, irrespective of the NaOCl solution used.