The antifungal effect of sodium hypo chloride in infected root canals with Candida albicans

Background: Whereas sodium hypochlorite is the most commonly irrigation solution used in
endodontics we set out to study its antifungal effect of sodium hypochlorite in infected root
canals with candida albicans.
Methods and Materials: In this study 160 human maxillary incisor teeth extracted for
different reasons were selected. The teeth were cut in the CEJ zone and then the canals were
prepared by using hand files and Gattes Glidden bur no. 6. The roots were then divided across
into 5- mm pieces and using diamond disks and chisel so the sample volume will become 320
pieces halved each 5- mm piece. The root samples were divided randomly into two groups of
150. In one of the groups in order to remove the smear layer with EDTA 17% and then 5.25%
sodium hypochlorite. The smear layer in the other group remained intact. In addition 10
samples were selected as positive control and 10 samples as negative control. The samples
were then sterilized separately by autoclave.
320 sterilized tissue culture plates were selected. Each root sample was fixed in the bottom
of a plate, and contaminated with candida albicans and then exposed to 2.5% and 5.25%
sodium hypochlorite. 25 samples were taken from each group in intervals of 5، 30 and 60
minutes and transferred to the T.S.B culture medium. After 24 hours, the tubes containing
T.S.B were considered in presence of turbidity. The results were statistically analyzed.
Results: The results indicated that 2.5% sodium hypochlorite in the present of smear layer
caused destruction of candida albicans after 5 minutes in 20% of the cases while such
destruction happened with 5.25% sodium hypochlorite in 44% of the cases. However by
increasing the disinfections period in both concentrations the antifungal effect appears in
100% of the cases. Moreover the results of the study indicated in the group with no smear
layer, sodium hypochlorite with a concentration of 2.5% showed its antifungal effect in 5
minutes in 36% of the cases and with a concentration of 5.25% in 100% of the cases.
Conclusions: Therefore the use of specific antifungal irrigation solution in the endodontic
therapy of patients having local or systemic predisposing factors to oral candidiasis extreme
importance.