牙齒在口腔環境中會不斷地進行再礦化(Remineralization)與去礦化 (Demineralization) 反應，當去礦化反應的速率大於再礦化就容易造成齲齒，因此若能早期發現將可以預防蛀牙的發生。由於光學同調斷層掃描系統(Optical Coherence Tomography, OCT)相較於其他技術具有非侵入性、高速成像、高解析度等優點，因此在此研究中我們利用光學同調斷層掃描觀察牙齒去礦化的早期變化，期待未來我們可應用光學同調斷層掃描於早期齲齒的檢測。
在此研究中，我們利用37%磷酸(Phosphoric acid etching gel)來模擬牙齒的酸性環境並加速實驗地進行，因此我們將37%磷酸塗於離體人類牙齒表面以產生酸蝕反應，另外我們利用頻域式光學同調斷層掃描系統(Spectral-Domain OCT)觀察牙齒去礦化過程中牙齒表面的型態變化與散射強度變化，另外也利用光學同調斷層掃描探討酸蝕的速率，由我們實驗結果驗證光學同調斷層掃描可定量牙齒酸蝕所產生的結構變化，可作為早期齲齒的檢測工具。

The teeth undergo constant remineralization and demineralization reactions in the oral environment. When the rate of demineralization is greater than remineralization, it is easy to cause dental caries, because early detection can prevent tooth decay. Because optical coherence tomography (OCT) has the advantages of non-invasive, high-speed imaging and high resolution compared to other techniques, in this study we used optical coherence tomography to observe the early demineralization of teeth. Looking forward to the future we can apply optical coherence tomography to the detection of early caries.
In this study, we used 37% phosphoric acid gel to simulate the acidic environment of the teeth and accelerated the experiment. Therefore, we applied 37% phosphoric acid to the surface of isolated human teeth to produce acid etching reaction. In addition, we used spectral-domain optical coherence tomography (Spectral-Domain OCT) was used to observe the changes of the shape and scattering intensity of the tooth surface during tooth demineralization. In addition, the optical coherence tomography was used to investigate the rate of acid etching, which was verified by our experimental results. Optical coherence tomography can quantify the structural changes caused by tooth erosion and can be used as a detection tool for early caries.

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