Commissure-Preserving Modification of the Gate Flap for Reconstruction of Large Lower Lip Defects

Reconstruction of lower lip defects requires techniques that preserve both aesthetics and essential functions such as speech and oral competence. While the unilateral gate flap, originally described by Fujimori, is a widely used option for subtotal and total lower lip defects, disruption of the oral commissure remains a major limitation. In this study, the unilateral gate flap was modified to preserve the oral commissure by de-epithelializing the proximal portion of the flap and advancing it through a subcutaneous tunnel. Between 2014 and 2022, 25 modified gate flaps were performed in 22 patients with lower lip defects involving ≥50% of the lip with commissure preservation. No cases of flap loss were observed. Minor complications included transient local edema and limited wound dehiscence, all of which resolved with conservative management. During follow-up, oral competence and continuity of lower lip function were maintained when the reconstructed segment represented the primary lower lip repair; 1 patient with prior free fibula flap reconstruction had persistent functional limitation. This commissure-sparing, single-stage modification permits preservation of the oral commissure while maintaining the fundamental reconstructive principles of the Fujimori flap. Rather than claiming outcome superiority, it is presented as a practical technical option for selected cases in which commissure preservation is oncologically appropriate.