(A616) Reconstruction of Small-To-Moderate Size Floor of Mouth Defects: A Retrospective Series and Analysis of Techniques

Introduction: Defects of the floor of mouth (FOM) present unique challenges due to their potential impact on speech and swallowing. The specific type of reconstruction for small-to-moderate size FOM defects can be controversial.

Methods: Retrospective review of patients who underwent resection of FOM malignancies at a single institution between January 2014 and October 2024. An operative report search engine was used to identify patients using the search term “floor of mouth”. Patients who had large resections of adjacent oral cavity subsites were excluded, although patients with marginal mandibulectomies or resection of the ventral tongue were included.

Results: Nineteen surgeries met inclusion criteria. There were 5 primary closures. Mean defect size was 5.66 cm2. Most tolerated oral intake with no tongue tethering. Two patients healed by secondary intention. Mean defect size was 4.64 cm2. No speech or diet issues were noted. One 12 cm2 defect was repaired with a full thickness skin graft. Five pedicled flaps were used, with 3 facial artery musculomucosal (FAMM) flaps, one supraclavicular flap revised with a FAMM flap, and one infrahyoid flap. Mean defect size was 29.91 cm2 (range 6.25-58.9). All required enteral feeding (6-16 days). Most experienced dysphagia but also had radiation. Four underwent a combination of techniques with the tongue closed primarily and the FOM repaired with a split thickness skin graft or secondary intention. No oral intake difficulties were noted and 75% described difficulties with speech. Two patients with T3 had radial forearm free flaps. Enteral feeding was required for 21-23 days but no tethering was noted on exam.

Conclusions: Various options exist for repair of FOM defects. Based on review of our institution’s experience, defects around 5 cm2 or less can be repaired by primary or secondary intention without negatively impacting function. When there is ventral tongue involvement, a combination technique can also be considered. When significant tongue involvement is present or the defect extends to the geniohyoid musculature, pedicled or free flap reconstruction was often required.