What duty can a dentist delegate to a hygienist?

The delegation of duties from a dentist to a dental hygienist is guided by specific regulations within Florida's laws governing dental practice. A dental hygienist is permitted to perform certain procedures under the supervision of a licensed dentist.

Marginating restorations without changing the contour involves refining and smoothing the edges of existing restorations, a task that can be delegated to a dental hygienist. This procedure is considered part of the hygienist's scope of practice, as it aligns with their training in maintaining and enhancing oral health, while still ensuring that the dentist ultimately oversees and is responsible for the patient's overall dental care.

In contrast, performing teeth whitening procedures typically requires more comprehensive oversight or intervention and is not generally within the scope of practice for hygienists unless specific training has been undertaken and permitted by the state. Extracting teeth is a surgical procedure that is reserved for licensed dentists due to its complexity and the potential for complications. Diagnosing dental conditions is also a responsibility that lies firmly with the dentist, as it requires comprehensive clinical judgment and training that extends beyond the hygienist's functions.

Thus, the ability to margin restorations without altering their overall contour exemplifies a task that utilizes a hygienist’s skills appropriately within their delegated authority, making it the correct answer.