早期齲齒病灶主要位於牙釉質，通常出現在牙齒之唇側面或鄰接面。針對早期齲齒病灶，目前被認為有效的表面處理方法為樹脂浸潤，市售商品名為Icon infiltrant，其宣稱可減緩早期齲齒病灶甚至終止病程。
關於應用Icon infiltrant於鄰接面齲齒的體內研究，普遍認為有良好的結果；於體外實驗則顯示Icon infiltrant有良好的滲透力，甚至對牙齒表面的硬度有正向幫助。
但也有研究指出窩溝封填劑比Icon infiltrant有較低的溶解度，以及被Icon infiltrant處理過的牙釉質仍需擔心染上污漬的問題。然而，目前只有少數文獻提及被Icon infiltrant處理過的牙齒表面於微觀下會有如何的材料表現。本研究之目的是比較樹脂浸潤材料Icon infiltrant與窩溝封填劑應用在人造早期齲齒病灶後的機械性質。
本研究屬於體外實驗，以牛門牙進行3天的酸鹼循環 (pH值為5.0)後製成人造早期齲齒病灶(early caries lesion)，再以樹脂浸潤材料(Icon infiltrant，Icon組)以及窩溝封填劑(UltraSeal XT® hydro，Seal組) 分別進行處理後，一半樣本浸泡於去離子水3天(Icon-T及Seal-T組)，另一半樣本則再次進行3天的酸鹼循環(Icon-R及Seal-R組)。之後以掃描式電子顯微鏡、能量散射光譜儀、表面粗度儀與奈米壓痕觀察樣本，比較兩種材料在再次酸鹼循環前後機械性質之差異。
本研究之結論為牛門牙早期齲齒病灶之表面處理，樹脂浸潤材料較窩溝封填劑來的粗糙，在奈米硬度方面，樹脂浸潤材料也較弱；若在材料皆未至牙齒表面脫落的情況下，兩者抗酸能力則無差異。

Early caries lesions are mainly located on labial and/or proximal surfaces of enamel. The most referred method of surface management is resin infiltration such as the Icon infiltrant. It was claimed to have the effects of decreasing or even eliminating the process of early caries lesion.
According to the previous studies, it is generally accepted that proximal caries could be treated with Icon infiltrant as an effective method in vivo. Other in vitro studies indicated that Icon infiltrant has a preferable penetration capability, and even showed the positive effect to the hardness of surface.
However, other study revealed that the solubility of sealants is lower than that of Icon infiltrant. In vitro studies also revealed that enamel treated with Icon infiltrant could be susceptible to staining. Moreover, the main content of Icon infiltrant is resin matrix, very few studies referred to the performance of Icon infiltrant at microscopic level. The aims of this study were to compare the mechanical properties between the resin infiltration material and the dental sealants on the artificial early caries lesions.
In this in-vitro study, we created artificial early caries lesions over bovine incisors by pH cycling (pH 5.0). The early caries lesions were treated with the resin infiltration material (Icon infiltrant, Icon group), or the fissure sealant (UltraSeal XT® hydro, Seal group). Half of Icon group and half of Seal group (Icon-T and Seal-T) placed in deionized water for 3 days, and the rest samples (Icon-R and Seal-R) were subjected to the second pH cycling (the second acid challenge). Scanning electron microscope (SEM), energy-dispersive X-ray spectroscopy (EDS), the surface profilometer and the nanoindentor were conducted to compare the mechanical properties and topography of these two materials before and after the second acid challenge.
The results of this study revealed the surface roughness of the resin infiltration being higher than the sealants but the nanohardeness of the resin infiltration being lower than the sealants. Both materials have the similar acid resistance under the 2nd acidic challenge.

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