Prevalence of Gummy Smile and Its Causes Among the Egyptian Population.

Inclusion Criteria: * patients attending El kasr el Aini hospital at the department of periodontology. * patients whose above 18 years old of both genders * patients consulting the outpatient clinic * provide informed consent Exclusion Criteria: * less than 18 years old * patients having problems opening their mouth or undergoing inter maxillary fixation where oral examination will not be possible * patients diagnosed with psychiatric problems or intoxicated with alcohol or drugs * patients with gingival hyperplasia * patients with extracted maxillary anterior teeth