Journal of Korean Academy of Oral Health (대한구강보건학회지), Vol.35(1) : 23~31, 2011
Journal of Korean Academy of Oral Health (대한구강보건학회지)
Objectives. The aim of this in vitro study was to examine the effect of polyacrylic acid (Carbopol 2050) concentration on producing
artificial carious lesions.
Methods. Sixty bovine enamel specimens were selected by the initial surface microhardness (SMH) by measuring the Vickers
microhardness number. The samples were immersed in five demineralizing gels with 0.2, 0.4, 0.6, 0.8 and 1.0% Carbopol 2050
for 96 hours to produce artificial carious enamel lesions. After demineralization, the SMH was measured again to calculate the
percentage of SMH reduction (⊿SMH%). The cross-sectional microhardness (CSMH) was assessed to determine total mineral loss
and total lesion depth. The Polarized light microscopy analysis was conducted to evaluate the lesion depth and the mineral distribution
of upper part of lesions.
Results. Based on the concentration of Carbopol 2050, the ⊿SMH% did not decrease. CSMH test revealed that total lesion depths
ranged from 84 to 96 μm. The total mineral loss was significantly greater in the 0.8% group than in the 0.2% group (p＜0.05).
According to PLM analysis, lesion depth to the dark layer was deeper in the higher concentration groups and mineral distribution
showed a distinct pattern in five groups. The surface zone was observed in the lesions but no clear feature was observed in the
higher concentration groups.
Conclusions. The concentration of Carbopol 2050 affected mineral distribution and mineral loss, but did not affect surface protection
and the total lesion depth of lesions.