RESUMO
BACKGROUND: Lower lip reconstruction aims to maintain facial subunit function and aesthetics. We present a minor modification of the McGregor flap technique, in which depressor anguli oris (DAO) muscle is separately elevated as a chimeric flap together to investigate the outcomes for reconstructing lower lip defects using various functional parameters. METHODS: The study included patients who underwent surgical repair of lower lip defects using a McGregor fan flap with or without DAO muscle chimeric flap between January 2018 and May 2021. The patients were divided into our modified technique with DAO chimeric flap (study group) and conventional McGregor (control group). The primary outcomes were functional evaluation of oral competency, speech intelligibility, and tactile sensation of reconstructed lip outcomes. The functional satisfaction and Patient and Observer Scar Assessment Scale (POSAS) were analyzed. RESULTS: A total of 20 patients were enrolled (10 patients for each group). Excellent oral competence was present in 12 patients, favorably significant in patients with DAO chimeric flap (n = 8/10, p = 0.018). All patients had intelligible speech with insignificant differences between the two groups. No patients demonstrated differences to light touch from baseline sensation at 1 year. Patients in the study group reported more lip function satisfaction (p = 0.049). The POSAS score indicates satisfaction with the appearance of all patients. CONCLUSION: McGregor fan technique combined with DAO muscle chimeric flap offers a good choice by maintaining sensory and motor functions. Our minor modification can ensure the integrity of the oral sphincter, leading to improved lower lip function.