Which type of cavity preparation is typically used in Class 5 pulp irritation tests?

• A. Full crown preparations
• B. Class 5 cavity preparations
• C. Class 1 cavity preparations
• D. Class 2 cavity preparations

Answer: (B)

For studies of how materials irritate the dental pulp, you want a cavity that exposes dentin in a predictable, repeatable way so the pulp’s response can be assessed consistently. A Class 5 cavity preparation fits this need because it is placed on the cervical area of the tooth and creates a shallow to moderate dentin exposure with relatively thin dentin walls toward the pulp. This proximity to the pulp and the exposed tubules allow irritants or restorative materials to contact dentin in a controlled manner, producing a measurable and reproducible pulp response across samples. Other types of preparations involve much more tooth structure removal or different locations (such as full-crown, occlusal Class I, or proximal Class II), which introduce different patterns of irritation and greater variability, making them less suitable for standard pulp response testing.