Do you have excessive gum showing when you smile? More importantly, does it embarrass you? Gummy smiles are typically caused by anything from a short upper lip, to teeth that have not grown properly inside your jaw. The good news is something can be done about it. Gummy smile correction can significantly improve your smile by reducing the length of the gums and relaxing your upper lip. Orthodontic treatment is sometimes necessary to correct gummy smile, in other cases jaw surgery may be required.