A dentist adjusts the shade ofa restoration using a complementary color．This procedure will result in()
A. increased value
B. decreased value
C. intensified color
D. increased translucency
Brittle materials have which of the following characteristics()
A. they undergo a lot of permanent deformation before fracturing
B. they tend to have a very ordered atomic structure
C. they respond poorly to tensile forces
D. A and B
你有6种材料，它们均可分类为后牙复合树脂，但它们各自的配方略有差异。你如何用花费最少、时间最短的试验来确定哪一种材料凝固后毒性最小？
在材料的机械性能测试中，去除外力后尺寸能够完全恢复的最大应力被称为()
A. 屈服极限
B. 强度极限
C. 弹性极限
D. 断裂极限
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