Orthodontic Assistant Practice Exam

Which material is typically used for making orthodontic study casts?

1. Gypsum

2. White orthodontic plaster

3. Composite resin

4. Wax

The correct answer is: White orthodontic plaster

The material typically used for making orthodontic study casts is white orthodontic plaster. This specific type of plaster is favored due to its fine particle size and excellent detail reproduction, which is essential for accurately reflecting the contours and details of dental structures. The resulting casts provide orthodontists with essential information for diagnosis and treatment planning. White orthodontic plaster is specifically designed for dental applications, ensuring that the casts can withstand the stress of manipulation and remain stable over time. This material allows for a smooth, even finish and is easy to work with, making it ideal for creating precise and durable models. In contrast, gypsum, while similar to plaster, typically does not have the same properties needed for orthodontic applications. Composite resin is used for various dental procedures, particularly restorations and repairs, but isn't suitable for creating study casts. Wax, although utilized in certain areas of dentistry for temporary impressions or to create bite registration, does not provide the solid, durable casts needed for long-term analysis in orthodontic treatment.