Which of the following is covered under restorative dental treatment?

Restorative dental treatment encompasses procedures aimed at restoring the function and aesthetics of the teeth that have been damaged due to decay, injury, or other dental issues. Crowns specifically fall into this category because they are placed over a damaged tooth to reinforce it and restore its shape, size, and strength. Crowns are commonly used to cover teeth that have undergone root canal therapy, have large fillings, or are misshapen or severely worn down.

In contrast, X-rays are diagnostic tools used to evaluate the condition of teeth and supporting bone, but they do not directly restore any dental function or structure. Cleanings are preventive measures designed to maintain oral health and prevent future dental issues, rather than a restorative treatment for existing problems. Dentures, while they are used to restore functionality and appearance for those who have lost teeth, are classified as prosthetic devices rather than restorative procedures specifically.

Therefore, crowns fit the definition of restorative dental treatment as they directly address and correct existing dental problems, making them the correct answer.