Lip Repositioning Surgery for Nonskeletal Excessive Gingival Display: A Clinical Case Report

Excessive gingival display, or gummy smile, caused by upper lip elevator muscle hyperactivity presents a significant esthetic challenge. This case report details the successful management of a 28-year-old female patient with an objectively measured dynamic gingival exposure of 4 mm. Preoperative evaluations confirmed normal clinical crown dimensions and healthy periodontal tissues, definitively ruling out altered passive eruption. The patient underwent conventional lip repositioning surgery (LRS) featuring a partial-thickness mucosal excision and meticulous wound closure with 6-0 polytetrafluoroethylene (PTFE) sutures to mechanically restrict upper lip mobility. The dynamic gingival display decreased from 4.0 mm preoperatively to 1.0 mm at 2 weeks and was stably maintained at 1.5 mm at the 1-year follow-up, meeting the treatment success criteria (≤ 2 mm). The procedure established a harmonious dentolabial relationship with high patient satisfaction and no complications, such as severe scarring, labial paresthesia, or relapse. These findings demonstrate that, based on accurate differential diagnosis and strict case selection, LRS serves as a safe, minimally invasive, and highly predictable intervention yielding excellent short-to-medium-term esthetic outcomes for muscular hyperactive gummy smiles.