National Dental Assisting Examining Board (NDAEB) Practice Exam

What effect does adding more water have on the consistency of gypsum product?

1. Makes it thicker

2. Improves strength

3. Reduces setting time

4. Increases fluidity

The correct answer is: Reduces setting time

Adding more water to a gypsum product significantly influences its consistency, and in particular, it increases its fluidity. When extra water is incorporated into the mixture, the gypsum is able to flow more easily, which is particularly useful for capturing detailed impressions in dental applications. Increased fluidity allows the gypsum to seep into tiny spaces and captures fine details, enhancing the quality of impressions and model-making. Conversely, using less water results in a denser and thicker consistency, which may not flow as easily and can lead to difficulty in achieving precise impressions. The relationship between water and gypsum is crucial because it also affects the setting time—more water typically results in a longer setting time rather than reducing it. Additionally, while it may seem intuitive that more water could improve strength, this is not the case; in fact, greater amounts of water can dilute the primary binding components, potentially weakening the final product. Thus, the most accurate outcome of increasing water in a gypsum product is that it increases fluidity, enhancing the material's workability and application in dental procedures.