Durability of Botulinum Toxin Type A and Qualitative Analysis for the Treatment of Gummy Smile due to Muscle Hyperfunction

This study evaluated the durability of botulinum toxin type A in 16 patients (n=16), with 08 units bilaterally, at different time points, through photographs and measurements at T0 (before application), T1 (20 days), T2 (2 months), and T3 (4 months). Two distance measurements were taken: (a) the distance from the anterior nasal spine to the lower edge of the upper lip, and (b) the distance from the lower edge of the upper lip to the incisal edge of the upper right central incisor. The effect of botulinum toxin type A on improving quality of life was assessed by analyzing patient satisfaction using the visual analog scale (VAS). The results indicate that, when measuring the distance from the anterior nasal spine to the lower edge of the upper lip at T3 (14.95 mm), the average distance was greater than at T0 (14.82 mm) but lower than at T1 (16.53 mm) and T2 (15.42 mm). Regarding the average distance between the lower edge of the upper lip and the incisal edge of the upper right central incisor, T3 (11.23 mm) was lower than T0 (12.11 mm) but higher than T1 (8.94 mm) and T2 (8.52 mm). In terms of patient satisfaction, the VAS score at T3 (10) was higher than at T0 (4.5), T1 (8.5), and T2 (9). Botulinum toxin type A qualitatively improved the patient's quality of life and exhibited a durability of at least four months.