The Yonsei Point: A Precision Approach to Gummy Smile Correction With Botulinum Neurotoxin

Abstract

Background: A gummy smile, or excessive gingival display (EGD), is a condition characterized by the visibility of more than 3 mm of gingiva during smiling. It often stems from hyperactivity of the lip elevator muscles, a treatable etiology. Botulinum neurotoxin (BoNT) offers a minimally invasive option for addressing this issue. This study introduces the Yonsei Point, a novel injection site targeting the convergence of key muscles to achieve precise and natural correction of EGD. Objective: To evaluate the effectiveness and safety of the Yonsei Point as a standardized technique for BoNT injection in the treatment of gummy smiles caused by hyperactive lip elevator muscles. Methods: Patients presenting with EGD due to hyperactive lip elevator muscles were included in this study. Exclusion criteria encompassed skeletal-based EGD, altered passive eruption, and prior BoNT treatments. The Yonsei Point was identified using anatomic landmarks: a vertical line drawn from the alar base and a lateral point 1 cm from this line, intersecting a horizontal line 3 cm above the cheilion. BoNT-A was injected bilaterally at this site (2-3 units per side) using a 30-gauge needle placed intradermally or subdermally. Post-procedural instructions included avoiding massage and strenuous activity for 4 to 6 hours. Results: A 33-year-old female with a 5-mm gingival display underwent BoNT-A injections at the Yonsei Point, receiving 3 units per side. Within 1 week, gingival display reduced to 2 mm, achieving an aesthetically pleasing smile. No complications were reported, and effects lasted similar to 4 months. Similar outcomes were observed in other patients treated with this technique. Conclusions: The Yonsei Point represents a precise, effective, and minimally invasive method for correcting gummy smiles caused by hyperactive lip elevator muscles. Its anatomic specificity minimizes complications while ensuring natural results. Further research is warranted to validate its utility across diverse patient populations and refine the technique for broader clinical adoption.