恆齒琺瑯質齲齒與氟化處理之阻抗分析

Impedance Analysis of Permanent Teeth Enamel with Dental Caries and Fluoride Supplementation

趙威濂(Wei-Lian Zhao)

指導教授 ： 傅昭銘

國立臺灣大學/理學院/物理學系/碩士(2022年)

https://doi.org/10.6342/NTU202204029

摘要

隨著人類飲食習慣的改變，齲齒的患病率不斷增加，時至今日已是人類最流行的疾病，而臨床上齲齒的診斷主要依賴X光影像的判讀，但當檢測到齲齒時蛀洞範圍已然擴散到相當大的程度。另一方面，有效的預防齲齒不僅是刷牙，還要塗上氟化物進行保護，但氟化物濃度與預防蛀牙的效期之間的關係仍不清楚，目前臨床使用的氟化鈉溶液濃度為10-3M，而衛生福利部建議是每三個月到半年塗氟一次。基於上述原因，本研究使用阻抗分析法，嘗試發展出一種新的齲齒檢測方法，並了解氟化物濃度與效期的關係。
在本研究中，我們使用是德科技之E4980A精密LCR測量儀對健康、齲齒和含氟牙齒進行了阻抗量測，琺瑯質的成分主要為3%的水分及97%的羥基磷灰石(Ca10(PO4)6(OH)2)，是一種類陶瓷材料，根據以往文獻其電阻可以達到數百萬歐姆，在獲取數據時另須克服界面電阻的問題，在齲齒及塗氟處理的分析中，分別採用了導電凝膠及銀膠，始降低接點與樣本之間的電阻、成功獲取阻抗數據。
在參數設定從頻率20 Hz到2 MHz，獲得了各頻率範圍的阻抗數據，將其轉換成奈奎斯特圖後，初步確認這種方法可以看出三者之間的差異，接著我們使用 ABC chemistry 的 EIS Spectrum Analyzer 進行阻抗頻譜分析並應用brick layer model的理論，推論出適合的等效電路模型，同時。在健康牙齒和齲齒部分，為了進一步分析和解釋得到的結果，我們參考等效電路和模數。其次，我們發現塗氟後牙齒的電學特性發生了變化，並了解到不同濃度的氟化物會一直持續在琺瑯質進行反應。
雖然琺瑯質是由生物體形成的組織，但仍然可以通過交流阻抗和等效電路來分析，在整個研究過程中，我們試圖模擬臨床情況進行測量，我們期待該工具在臨床診斷中的實際應用，以及未來對人體物理特性的進一步了解。

關鍵字

交流阻抗分析 ； 齲齒 ； 塗氟處理 ； 模數

並列摘要

The prevalence of dental caries has been increasing with the change of human dietary habits. But the diagnosis of dental caries today only relies on X-ray detection. On the other hand, effective prevention is not only brushing but also applying fluoride for protection. But the relationship between fluoride concentrations and effectiveness in preventing tooth decay remains unclear. For the above reasons, to develop a new caries detection method and to understand the effective time of fluoride protection, we tried to use the impedance spectra analysis method.
In this study, we performed impedance measurements on healthy, carious and fluoride teeth using the Keysight E4980A precision LCR meter. However, the resistance of teeth can reach millions of ohms, so we first overcome the problem of interface resistance. After obtaining the impedance data of the sample from frequency 20 Hz to 2 MHz and converting it into a Nyquist plot, it was initially confirmed that this method can see the difference between each other. Next, we used the EIS Spectrum Analyser from ABC chemistry for impedance spectra analysis. First, in the section of healthy teeth and caries, in order to further analyze and interpret the obtained results, we refer to the equivalent circuit and modulus. Second, we found that the electrical properties of teeth changed after fluoride application, and learned that different concentrations of fluoride produced different protective effects.
Finally, From the results, although enamel is a tissue formed by living organisms, it can still be analyzed by impedance and equivalent circuit. Throughout the study, we tried to simulate clinical situations for measurements. We look forward to the practical application of this tool in clinical diagnosis and further understanding of the physical properties of the human body in the future.

並列關鍵字

AC impedance analysis ； dental caries ； fluoride treatment ； electrical modulus

參考文獻

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