What characteristic is unique to performed crowns?

The uniqueness of performed crowns lies in their material composition and manufacturing process. Unlike traditional crowns that may require a detailed impression of the patient’s tooth structure and customized shaping to fit perfectly, performed crowns are pre-made, often with specific materials like polycarboxylate or polymers designed for durability and aesthetics.

These crowns are typically fabricated using precise techniques in a manufacturing setting, which means they are not made directly for the individual patient. Instead, they come in various pre-determined shapes and sizes, allowing for a quicker application in clinical settings. This characteristic allows dental professionals to offer more efficient treatment options, as performed crowns can often be placed without the detailed custom fitting necessary in other crown procedures.

The other answers highlight aspects that do not differentiate performed crowns. For instance, needing detailed impressions is typical of custom dental crowns rather than performed ones. Furthermore, the idea that they can only be used for anterior teeth is inaccurate, as performed crowns are available for posterior teeth as well. Lastly, while all properly made crowns should fit well, stating they are "always custom-made in the lab" contradicts the fundamental nature of performed crowns, which are, by definition, mass-manufactured rather than individually crafted.