Which of the following materials is commonly used for temporary restorations?

Zinc oxide eugenol is commonly used for temporary restorations due to its beneficial properties. One key advantage of this material is its ability to provide a soothing effect on the dental pulp, which is particularly important when a tooth has been recently treated or is sensitive. Additionally, zinc oxide eugenol has excellent sealing properties, minimizing microleakage and protecting the underlying tooth structure from bacteria and irritants.

This material is also easy to manipulate and can be quickly set, making it suitable for temporary applications where a fast turnaround is needed before a more permanent restoration is placed. Its relatively low cost and availability further enhance its desirability for temporary restorations.

In contrast, dental porcelain, amalgam alloy, and ceramic resin are generally used for more permanent restorations due to their durability, esthetics, and strength. These materials are not typically suited for temporary restorations, as they require more complex setups and processing, which is not ideal for short-term use.