Analysis of active chlorine releasing and pH of sodium hypochlorite solutions used in Endodontics

Resumo

The use of a suitable irrigation solution and a correct
root system shape effectively contributes to the success of endodontic
treatment. Among the irrigating solutions used in Endodontics,
sodium hypochlorite has been the most used because of many
qualities. However, this substance must have chemical stability of
its properties, by maintaining the potential of hydrogen (pH) and
chlorine concentrations appropriately. Objective: The aim of this
study was to evaluate active chlorine releasing and pH of some sodium
hypochlorite solutions used in endodontic clinical practice. Material
and methods: The solutions tested in this study were 0.5% Dakin,
1% Milton, 2% Chlorinated Soda, and household bleaches (Brilux®
and Qboa®), which were opened at the same period and first used,
with the same storage modus but with different manufacturing
dates. The pH was measured with a digital device, and the active
chlorine content was obtained through iodometric titration. Results:
All solutions presented chlorine content not smaller than that
informed in the flasks, ranging from 1% to 2.4%; pH was higher in
all solutions, between 9 and 13. Conclusion: Based on the method applied and the results obtained, it was possible to conclude that
sodium hypochlorite solutions used specifically in Dentistry (Dakin
and Milton solutions and Chlorinated Soda), showed on the labels
the hypochlorite content. On the other hand, household bleaches
(Brilux® and Qboa®) showed the chlorine content. It was not possible to
compare pH authenticity, due to lack of description on the label.