Evaluation of a neurotoxin as an adjunctive treatment modality for the management of gummy smile

Abstract

Introduction: Excessive gingival display while smiling mars facial aesthetics, this condition is referred to as 'gummy smile' (GS). Available literature suggests that Botulinum toxin type A (BTX-A) is effective in the management of excessive gingival display by denervating hyperfunctional muscles. This study was conducted to statistically assess the effects of BTX-A for the management of GS. Materials and Methods: A total of 10 patients between the ages of 18-27 years were selected for this study, they received BTX-A (Botox; Allergan, Irvine, CA, USA) injections for reduction of excessive gingival display at 'Yonsei point' on both sides. Gingival display was measured as the vertical distance from the zenith of the gingiva of the upper right central incisor to the inferior border of the upper lip before beginning treatment (T0). The patients were then recalled after 15 days to measure the gingival display (T1). Standardized photographs to document changes were obtained at T0 and T1. Results: A statistically significant reduction in gingival display, while smiling was observed from T0 (7.5 ± 1.35 mm) to T1 (3.2 ± 0.91 mm) in all 10 patients (t = 16.5168, P value = 4.87, P < 0.05). Conclusions: Administration of BTX-A is recommended as an adjuvant to orthodontic treatment where the GS is caused due to hyperfunctional upper lip elevator muscles.