Patient with a very short clinical crown — what preparation design is most appropriate?

Correct answer: D. PFM with shoulder (shoulder provides more surface area for retention on short preps)

• A. A metal-only crown is not specified as necessary here; the question focuses on margin/preparation design appropriate for short crowns generally in a PFM context.
• B. While a shoulder margin design is correct, an all-metal crown is not the indicated restoration type in this scenario per the source material.
• C. A chamfer margin provides less surface area/retention than a shoulder, making it less ideal for a short crown requiring maximum retention.
• D. Correct. A PFM crown with a shoulder margin design provides increased surface area for retention/resistance form, which is especially beneficial when preparing a tooth with limited (short) clinical crown height.