Final answer:
Intermediate restorative materials, also known as dental amalgam, should be selected when a tooth has decay or damage that is not severe enough for a crown but too extensive for a regular filling.
Step-by-step explanation:
When a tooth has decay or damage that is not severe enough to require a crown, but too extensive for a regular dental filling, an intermediate restorative material should be selected. Intermediate restorative materials, also known as dental amalgam, are used to restore the structure and function of a damaged tooth. They are a mixture of metals, such as silver, tin, copper, and mercury. Dental amalgam is chosen because it is durable, long-lasting, and able to withstand the forces of chewing.