PDF(Pubmed)
Abstract：
This study aimed to compare the color change of computer-aided design (CAD)/computer-aided manufacturing (CAM) polymethyl methacrylate (PMMA) denture teeth and conventional acrylic teeth after immersion in three staining beverages (coffee, red tea, and cola) for a day, 7 days, and 30 days.
Group 1: Conventional acrylic teeth (n = 32). Group 2: Milled CAD/CAM teeth out of PMMA disc (n = 32). The specimens of each material were further divided into four subgroups: (1) Control group, distilled water (n = 16). (2) Red tea solution (n = 16). (3) Coffee solution (n = 16). (4) Cola (n = 16). The color change ( ∆ E $\\unicode{x02206}E$ ) was assessed using a spectrophotometer at four time points: at the baseline (t0 ), on the 1st day (t1 ), on the 7th day (t2 ), and the 30th day (t3 ) of immersion. Kolmogorov-Smirnov test was applied, followed by performing independent samples t test, one-way analysis of variance and post-hoc Tukey tests to compare the color change values at different time points.
The mean score of NBS values of the coffee solution indicates perceivable color change at the end of the 30th day in the conventional acrylic teeth group. It was 0.843 ± 0.395 at t1 , then increased to 1.017 ± 0.477 at t2 and to 2.259 ± 1.059 at t3 . There is a statistically significant difference (p < 0.05) in color change values between both tooth types at the end of the 30th day of immersion in red tea solution and a statistically significant difference at the end of the 7th day (p < 0.05) and the 30th day (p < 0.05) of immersion in coffee solution.
CAD/CAM PMMA teeth are more color stable than conventional acrylic teeth after 30 days of immersion in coffee and red tea solution.
Group 1: Conventional acrylic teeth (n = 32). Group 2: Milled CAD/CAM teeth out of PMMA disc (n = 32). The specimens of each material were further divided into four subgroups: (1) Control group, distilled water (n = 16). (2) Red tea solution (n = 16). (3) Coffee solution (n = 16). (4) Cola (n = 16). The color change ( ∆ E $\\unicode{x02206}E$ ) was assessed using a spectrophotometer at four time points: at the baseline (t0 ), on the 1st day (t1 ), on the 7th day (t2 ), and the 30th day (t3 ) of immersion. Kolmogorov-Smirnov test was applied, followed by performing independent samples t test, one-way analysis of variance and post-hoc Tukey tests to compare the color change values at different time points.
The mean score of NBS values of the coffee solution indicates perceivable color change at the end of the 30th day in the conventional acrylic teeth group. It was 0.843 ± 0.395 at t1 , then increased to 1.017 ± 0.477 at t2 and to 2.259 ± 1.059 at t3 . There is a statistically significant difference (p < 0.05) in color change values between both tooth types at the end of the 30th day of immersion in red tea solution and a statistically significant difference at the end of the 7th day (p < 0.05) and the 30th day (p < 0.05) of immersion in coffee solution.
CAD/CAM PMMA teeth are more color stable than conventional acrylic teeth after 30 days of immersion in coffee and red tea solution.
摘要：
目的：本研究旨在比较计算机辅助设计（CAD）/计算机辅助制造（CAM）聚甲基丙烯酸甲酯（PMMA）义齿和常规丙烯酸牙齿浸入三种染色饮料（咖啡，红茶,和可乐)一天，7天,和30天。
方法：第1组：常规丙烯酸牙齿（n=32）。第2组:从PMMA盘铣削出的CAD/CAM齿(n=32)。将每种材料的标本进一步分为四个亚组：（1）对照组，蒸馏水（n=16）。(2)红茶溶液(n=16)。(3)咖啡溶液(n=16)。(4)可乐(n=16)。使用分光光度计在四个时间点评估颜色变化（ΔE$\\unicode{x02206}E$）：在基线（t0），在第一天（t1），在第7天（t2），和浸入的第30天(t3)。采用了Kolmogorov-Smirnov试验,然后进行独立样本t检验，单向方差分析和事后Tukey测试，以比较不同时间点的颜色变化值。
结果:咖啡溶液的NBS值的平均得分表明在常规丙烯酸牙齿组中在第30天结束时可感知的颜色变化。t1时为0.843±0.395,然后在t2时增加到1.017±0.477，在t3时增加到2.259±1.059。在浸入红茶溶液的第30天结束时,两种牙齿类型之间的颜色变化值存在统计学上的显著差异(p<0.05),并且在浸入咖啡溶液的第7天(p<0.05)和第30天(p<0.05)结束时存在统计学上的显著差异。
结论：在咖啡和红茶溶液中浸泡30天后，CAD/CAMPMMA牙齿的颜色比常规丙烯酸牙齿更稳定。
方法：第1组：常规丙烯酸牙齿（n=32）。第2组:从PMMA盘铣削出的CAD/CAM齿(n=32)。将每种材料的标本进一步分为四个亚组：（1）对照组，蒸馏水（n=16）。(2)红茶溶液(n=16)。(3)咖啡溶液(n=16)。(4)可乐(n=16)。使用分光光度计在四个时间点评估颜色变化（ΔE$\\unicode{x02206}E$）：在基线（t0），在第一天（t1），在第7天（t2），和浸入的第30天(t3)。采用了Kolmogorov-Smirnov试验,然后进行独立样本t检验，单向方差分析和事后Tukey测试，以比较不同时间点的颜色变化值。
结果:咖啡溶液的NBS值的平均得分表明在常规丙烯酸牙齿组中在第30天结束时可感知的颜色变化。t1时为0.843±0.395,然后在t2时增加到1.017±0.477，在t3时增加到2.259±1.059。在浸入红茶溶液的第30天结束时,两种牙齿类型之间的颜色变化值存在统计学上的显著差异(p<0.05),并且在浸入咖啡溶液的第7天(p<0.05)和第30天(p<0.05)结束时存在统计学上的显著差异。
结论：在咖啡和红茶溶液中浸泡30天后，CAD/CAMPMMA牙齿的颜色比常规丙烯酸牙齿更稳定。
