Four-dimensional observation of remineralization phenomenon with carious lesion using micro CT method and laser irradiation.

我们用激光照射牙齿表面，观察牙齿表面脱矿后的龋损恢复情况。本研究的目的是研究CO2激光照射后牙釉质的质量。这些观察是通过微型CT进行非破坏性的。以钙化的时间轴变化和病变范围的扩大程度评价序列定量变化。我们用光滑表面有白斑的磨牙进行实验。为了观察龋的恢复情况，我们对白斑进行了CO2激光照射和氟化钠应用的组合。我们在拍摄微CT后的三维图像中观察了样品。结果表明，激光照射样品的脱矿深度有显著差异。本研究提示牙表面涂覆剂和CO2激光照射可能是牙表面下脱矿的有效区域。

We clarified the caries lesion recovery by the laser irradiation on the tooth surface, using human molars with subsurface demineralization. Purpose of our study is the quality of enamel after a CO2 laser radiation. These observations are done non-destructively by means of micro CT. Sequential quantitative changes was evaluated with the time axis variation of the calcification and the degree widening range of lesion. We used the molars having a white spot caries in smooth surface for experiments. In order to observe the recovery of caries, we performed the combination of CO2 laser irradiation and sodium fluoride application to the white spot. We have observed samples in the 3D image after shooting micro CT. As results, it was a significant difference in demineralization depth in a sample of laser irradiated sample. We suggested the possibility of the tooth surface coating agent and irradiation of the CO2 laser is effective area of subsurface demineralization from this study.