California Registered Dental Assistant (RDA) Written Practice Exam

How is irreversible hydrocolloid typically mixed?

1. In a cup with a spoon

2. In a mixing bowl with a spatula

3. Using an electric mixer

4. By shaking in a sealed bag

The correct answer is: In a mixing bowl with a spatula

Irreversible hydrocolloid, commonly known as alginate, is typically mixed in a mixing bowl with a spatula to ensure a consistent and homogenous mixture. Mixing in a bowl allows for adequate space to blend the material without spilling, while the spatula can effectively incorporate the water and dry powder together, breaking up any clumps that may form. It is crucial to achieve a smooth and uniform consistency for optimal results when making impressions. The other methods listed may not provide the same level of control or uniformity. For instance, mixing in a cup with a spoon could lead to inadequate mixing, resulting in an uneven mixture that can negatively affect the impression quality. Using an electric mixer might introduce excess air into the mix, which can create bubbles and compromise the integrity of the impression. Shaking in a sealed bag would not allow for proper blending and would likely result in a lumpy mixture, failing to produce the smooth consistency required for effective impressions.