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Silicone differs from polyether polymer with respect to:

 # Silicone differs from polyether polymer with respect to:
A. Affinity for water
B. Place and time of one
C. Area of one
D. Cost effectiveness



The correct answer is A. Affinity for water.

One of the disadvantages of the silicone impression materials (including condensation silicones) is their inherent hydrophobic nature. A nonionic surfactant can be added to the paste in the manufacturing process to render a degree of hydrophilicity to the surface of the material. This surfactant migrates toward the surface of the impression material and has its hydrophilic segment oriented toward the surface—a phenomenon that makes the surface more wettable by water. These impression materials still require a dry field for impression making. Pouring the set impression with a gypsum forming
mixture is facilitated because the wet stone has a greater affinity for the hydrophilic surface. The clinical significance of hydrophilic additives is discussed in subsequent sections.

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