Effect of bleaching agents on dentin permeability to Streptococcus
faecalis.
Author: Heling I; Parson A; Rotstein I
Source: J Endod 1995 Nov; 21(11):540-2
Abstract:
Bacterial contamination of dentin may be a contributing
factor in the development of bleaching-associated root
resorption. In this study, the effect of commonly used
bleaching agents on the permeability of dentin tubules
to Streptococcus faecalis was evaluated. Sixty extracted
bovine incisors were horizontally sectioned apically to
the cementoenamel junction. In each tooth, a standard cavity
was prepared, the pulp tissue extirpated, and remnants
of soft tissue and smear layer were removed. Following
rinsing and repeated autoclave sterilization, the teeth
were divided into four groups, each treated with one of
the following materials: 30% hydrogen peroxide, sodium
perborate mixed with 30% hydrogen peroxide, sodium perborate
mixed with distilled water, and distilled water alone that
served as control. The bleaching agents were sealed in
the teeth and incubated at 37 degrees C for 7, 14, and
21 days. At each time interval the bleaching agents were
removed and the teeth incubated at 37 degrees C in brain
heart infusion infected with S. faecalis. Histological
sections were prepared, and the maximal bacterial penetration
for each group was measured using a computerized morphometric
system. Statistical analysis of the results revealed that
teeth treated with either 30% hydrogen peroxide alone or
in combination with sodium perborate were significantly
more permeable to S. faecalis than those treated with sodium
perborate mixed with water (p < 0.0001). Sodium perborate
mixed with water did not cause an increase in dentin permeability
to S. faecalis and was similar to the water control. In
conclusion, it seems that bleaching agents containing hydrogen
peroxide in high concentrations may increase bacterial
penetration through dentinal tubules.
Copyright © 2021 oxygentherapyexperts. All rights reserved.