Daughter has normal size teeth but when she smiles you can still see her gums? what causes a gummy smile?

Lip: She may have a high lip line. A dental exam could confirm this.

High lip line: The position of her maxilla and the relationship to her face in toto helps to determine a high or low lip line. Not really related to the size of the teeth.

Gummy smile: There are four main causes: an overgrowth of the upper jaw; a short upper lip: individuals with short upper lips show more of their incisors at rest and more of their gums when they smile; a hyperactive upper lip (some individuals tend to overstretch their lips when they smile because they have hyperactive tight facial muscles); an overgrowth of gum tissue.

Gummy smile: Maxillary excess. This mean the upper jaw grew downward in excess.

Genetics: Usually inherited anatomy. Lip length, vertical height of upper jaw bone, lip position. Also protrusion causes upper lip to roll up/back. Deep overbite causes more gingival show. Excess gum tissue sometimes a problem. The dental specialist best trained to advise you as to appropriate treatment is an Orthodontist. Go find out. Initial examination usually complimentary.