Violation

If a tooth has an inadequate ferrule, which of the following is/are effective strategies to increase tooth structure available for crown preparation? 1. Surgical crown lengthening. 2. Sub-gingival preparation and prolonged temporization. 3. Orthodontic eruption. 4. Elective endodontic treatment gaining retention from a post in the root.

(1) and (3)

All of the above.