Plan the shape around cleaning and function
A space can look different from the front than it does from the side. Before closing it, the dentist needs to consider where the new contact will sit and how the gum will relate to the added material. A wider tooth should still allow an effective cleaning routine, including access near the gumline.
Discuss any food trapping you already experience. Closing the visible part of a space does not automatically solve the reason food collects there. The clinician may need to assess tooth position, the contact and gum support together.
If several teeth are involved, ask whether the proposed additions will look balanced across your smile. Changing one contour can affect the appearance of the tooth beside it. A photograph or other planning record may help you understand that relationship before work starts.
It is also worth discussing what happens if the composite later stains or chips. Find out which changes can reasonably be polished or repaired and when replacement would be considered. That conversation gives you a more useful comparison with ceramic work than a single promised lifespan.