Background: Excessive gingival display or "gummy smile" is a clinical condition where a maxillary gum shows between the inferior line of the superior lip and the gingival line of the incisive superior during a spontaneous smile. The aim of this research was to understand the various skeletal and dentoalveolar components contributing to a gummy smile in a sample of 120 patients.
Material and methods: This retrospective case-control study had the primary objectives of analyzing the existence of a correlation between the presence of gingival exposure and the alteration of the inclination of the upper incisors with respect to the Frankfurt plane, the Palatine plane (bi-spinal) and to the NA line in a sample of orthodontic patients, and also evaluating the association with skeletal, dental, and aesthetic cephalometric parameters.
Result and conclusions: In our study, it's emerged a correlation between the gingival exposure and the presence of alterations to incisal torque in the vestibular direction and the quantity of maxillary gingiva evident during the smile, which is correlated in particular to the Is-Sts distance, overjet and overbite. The major indicative data, therefore, are related to the vertical position of the upper incisors, in particular with respect to the upper lip and to the sagittal position.
Keywords: cephalometric parameters; gingival display; gummy smile; incisal inclination; orthodontics.