Which secondary function does a spoon excavator serve?

A spoon excavator primarily serves the function of removing carious dentin and debris from cavities, and it can also be used to remove temporary crowns. This makes it especially useful in restorative dentistry when there is a need to access the tooth structure beneath a temporary crown without causing damage to the underlying tooth.

The design of a spoon excavator allows for easy access to the interior of the tooth, where a clinician can gently scoop out materials such as old filling materials or temporary crowns, thus facilitating the restorative process. This tool's curved blade and handle provide better control and reach, which is essential when dealing with delicate structures in the mouth.

In contrast, other functions listed do not align with what a spoon excavator is used for. For instance, administering local anesthetics is typically done with syringes rather than hand instruments like a spoon excavator. Beveling cervical walls refers to the preparation of cavity margins, which is more commonly done with hand instruments designed specifically for that purpose. Cleaving enamel involves the use of certain types of chisels or burs rather than a spoon excavator, as it is more about shaping and adjusting enamel surfaces. This highlights the specific role of the spoon excavator in restorative procedures, particularly in relation to temporary crowns.