Abstract:

Objective To observe the clinical effect of the modified M-shaped flap for repairing defects following resection of lower lip cancer and to provide a reference for clinical application.Methods Fourteen cases using modified M-shaped flaps to repair lower lip cancer surgery defects were retrospectively analyzed. The postoperative follow-up patients’ flap survival, mouth opening, denture use, bilateral mouth angle symmetry, recurrence and survival were analyzed.Results Fourteen patients with lower lip cancer underwent reconstruction immediately after surgery, and the defect range after tumor resection was 30% to 50% of the lower lip. The continuity of the orbicularis oculi muscle is reconstructed by modified M-shaped flap to transfer bilateral residual lip tissue. The blood supply to the flap is stable. All patients’ flaps survived completely without complications, such as hemorrhage, infection or flap necrosis, and their lip movement and sensation recovered well. There were no obvious obstacles in opening and closing or pronunciation and dietary function, and the mean maximum opening was (3.06 ± 0.23) cm. Three patients used active dentures, which could be removed normally. All patients’mouths were preserved. Approximately 85.7% of patients (12/14) had bilateral symmetry of the bilateral mouth, the flaps matched the facial color, and the lower lip was naturally beautiful, as the scar was not obvious. After 6 months to 4 years of follow-up (mean 2 years and 6 months), no recurrence or death occurred.Conclusion The modified M-shaped valve design is simple and easy to operate. This method can be applied to 30% to 50% defect reconstructions of the lower lip to retain the corner of the mouth.

Key words: modified M-shaped flap, lower lip cancer, defect repair, flap, pedicle flap, sliding flap, orbicularis oris muscle