What characteristic describes a shoulder margin?

The shoulder margin is characterized by its ability to provide more bulk to the restoration. This feature is particularly beneficial in prosthodontics because it allows for a more robust interface between the tooth structure and the restorative material, which enhances the strength and durability of the final restoration. The shoulder margin's design can support thicker occlusal surfaces, making it especially advantageous when fabricating crowns or bridges that require additional strength, such as those used for posterior teeth that endure significant chewing forces. This bulk is also instrumental in achieving proper alignment and stability for the restoration once it is placed in the oral cavity.

While the other characteristics mentioned may relate to other types of margins, they do not accurately describe what is most distinctive about shoulder margins in the context of restorative dentistry. For instance, shoulder margins can be crafted to achieve a more aesthetic finish, particularly when combined with ceramic materials, thereby not limiting them in terms of aesthetic appeal.