| 摘要: | 實驗目的；牙科複合樹脂常用於美觀區域的復型。本研究之目的在比較牙科充填用奈米複合樹脂及傳統複合。
實驗步驟；實驗材料包括5種牙科奈米複合樹脂：(1) Gradia○R Anterior (Voco公司)、(2) Grandia○R Posterior (Voco公司)、(3) Mono○R(Dentsply公司)、(4) FiltekTM Z350○R (3M公司)、(5) Esthet○R (Dentsply公司)，以及3種牙科傳統複合樹脂：(1) Primedent○R (Prime Dental Manufacturing公司)、(2) Spectrum○R (3M公司)、(3) FiltekTM Z100○R (3M公司) 。經過不同溶液(1)蒸餾水(2)酒精(3)醋酸(4)醬油(5)紅茶各浸泡15天後，分別測試其機械性質：(1)吸水量變化(2)顏色變化(3)表面粗度(4)表面硬度，每次測試皆重複5次，以two way ANOVA及paired t test 分析比較浸泡前後差異、奈米與傳統複合樹脂間差異（p value<0.05)。
實驗假設；預期奈米材料有較好的性質表現。
實驗結果；
(1)吸水量變化：奈米樹脂吸水量並非一定比傳統樹脂少，醋酸對Primedent○R，Spectrum○R，Gradia○R Anterior，Grandia○R Posterior, FiltekTM Z350○R, Esthet○R 吸水量有顯著影響（p<0.05）
(2)顏色變化：奈米樹脂色差值並非一定比傳統樹脂少，醋酸對Primedent○R，Spectrum○R，Grandia○R Posterior，Mono○RFiltekTM Z350○R, Esthet○R 色差值有顯著影響（p<0.05）。
(3)表面粗度；奈米樹脂浸泡後表面粗度並非一定比傳統樹脂小，醋酸對所有材料Primedent○R， Spectrum○R，FiltekTM Z100○R，Gradia○R Anterior，Grandia○R Posterior，Mono○RFiltekTM Z350○R, Esthet○R 表面粗度有顯著影響（p<0.05）。
(4)表面硬度；浸泡後所有材料表面硬度皆有下降（p<0.05）。 Primedent○R， Spectrum○R，FiltekTM Z100○R，Gradia○R Anterior，Grandia○R Posterior，FiltekTM Z350○R, Esthet○R 在醋酸中表面硬度最低。 (p<0.05)。
結論； 本實驗無法證實奈米樹脂的蓮花效應、自淨作用、表面粗度穩定性、表面硬度穩定性如同外界聲稱之好。本實驗發現醋酸對大部分的材料性質有明顯的影響。樹脂材料特性並不能用傳統樹脂與奈米樹脂的分類一概而論，材料特性仍須分別探討。
Purpose；Dental composite resin is commonly used for restoration in esthetic area. The purpose of this study is to compare mechanical properties of dental nanocomposite and conventional composite.
Materials and Method；Five brands of nanocomposite were selected to be investigated, (1) Gradia○R Anterior (Voco, Germany), (2) Grandia○R Posterior (Voco, Germany), (3) Mono○R(Dentsply, Germany), (4) FiltekTM Z350○R (3M, USA), and (5) Esthet○R (Dentsply, USA). Three brands of conventional composite were selected to be researched, (1) Primedent○R (Prime Dental Manufacturing, USA), (2) Spectrum○R (3M, USA), (3) FiltekTM Z100○R (3M, USA) . Every material were soaked in five liquids ; each for 15 days, (1)diluted water, (2)alcohol, (3)acetic acid, (4)black tea, (5)soy bean sauce. Before and after 15 days immersion each specimen was tested and repeated 5 times. Mechanical properties such as (1)water immersion, (2)color change, (3)surface roughness, and (4)surface hardness were recorded and statistically analyzed with paired t test and two-way ANOVA. A significance level of p-value < 0.05 was chosen.
Hypothesis: All nanocomposites have better mechanical properties.
Results: (1)Water immersion: Not all nanocomposites have less water immersion than conventional composites. Acetic acid has significant effect at water immersion of Primedent○R, Spectrum○R, Gradia○R Anterior, Grandia○R Posterior, FiltekTM Z350○R, and Esthet○R （p<0.05）
(2)Color change: Not all nanocomposites have less color change than conventional composites. Acetic acid has significant effect at color change of Primedent○R, Spectrum○R, Grandia○R Posterior, Mono○RFiltekTM Z350○R, Esthet○R（p<0.05）。
(3)Surface roughness: After 15 days immersion, not all nanocomposites have lower surface roughness than conventional composites. Acetic acid has significant effect at surface roughness of Primedent○R, Spectrum○R, FiltekTM Z100○R, Gradia○R Anterior, Grandia○R Posterior, Mono○RFiltekTM Z350○R, and Esthet○R（p<0.05）。
(4)Surface hardness: After 15 days immersion, all materials have lower surface roughness than before immersion（p<0.05）. Acetic acid has significant effect at surface hardness of Primedent○R, Spectrum○R, FiltekTM Z100○R, Gradia○R Anterior, Grandia○R Posterior, FiltekTM Z350○Rand Esthet○R (p<0.05). |
