At what stage is Endodontic treatment considered complete?

Endodontic treatment involves removing diseased or damaged tissue from inside a tooth's root canal and replacing it with a filling material. While filling the root canal (choosing option A) is a major part of the treatment and brings relief to the patient, endodontic treatment is not considered complete until the final step of placing a coronal restoration (choosing option C). This restoration, such as a filling or crown, is needed to seal and protect the tooth from further damage and potential infection. Extracting the tooth (choosing option B) would not be considered successful completion of the treatment. While placing a crown (choosing option D) is a necessary step in preserving the tooth after endodontic treatment, it is not the final step and can only occur once the coronal restoration is complete. Therefore, the correct answer is C.