OBJECTIVETo investigate the effect of ozone on remineralization of enamel in vitro.

METHODSCaries-like lesions were prepared in the enamel of extracted cattle incisors with demineralizing solution. The specimens were treated with deionized water, 1000 mg/kg fluoride, 4.5 mg/L ozone, and pH-cycled. The scanning electron microscope (SEM) was used to observe the surface of enamel specimens. The effect of remineralization was assessed by three lesion parameters (fluorescent area, total and average fluorescence), which were measured with confocal laser scanning microscope (CLSM). The data were collected and analyzed by SNK test in ANOVA.

RESULTSSEM observation showed that the surface morphology of the deionized water group and ozone group were similar: porous and atactic; but the surface morphology of fluoride group was smooth and the aperture became smaller. The three parameters in the three groups were as follows, respectively. Delta A were (0.31 +/- 0.28), (1.73 +/- 0.63) and (0.28 +/- 0.19) x 10(4) microm2, Delta TF were (0.42 +/- 0.34), (2.53 +/- 0.73) and (0.48 +/- 0.27) x 10(5), Delta AF were (3.35 +/- 2.55), (46.51 +/- 16.64) and (4.95 +/- 3.05). The fluoride group was significantly greater than deionized water group and ozone group (P < 0.05); but there was no significant difference between the deionized water group and ozone group.

CONCLUSIONSThe results of this in vitro study suggest that ozone has no effect on remineralization of enamel blocks.