Even if a gummy smile is not considered a medical condition, we can still discuss what the causes of a gummy smile are. Obviously, these causes are all related to the teeth, lips, jaws or gums, which happen to be the key components that dictate a person’s smile aesthetics.

The most common causes of a gummy smile include:

Teeth that appear short and remain partially covered by gum tissue

Teeth that are small in comparison to the gums, mainly due to genetics

An upper lip that is too short to cover the gums

An upper lip that is normal in length when the face is resting, but lifts too high when smiling, hence exposing a lot of gum tissue

Gingival hypertrophy (enlarged gum tissue)

Maxillary excess (an overgrowth of the upper jaw that makes gums bulge out)

Usually, the condition behind a gummy smile is genetic, so there’s nothing you can do to prevent it.