The aim of this study was to estimate the overall viability of the islanded facial artery myomucosal flap (iFAMM) compared to the facial artery myomucosal flap (FAMM). A systematic review of English articles was performed on PubMed and Cochrane Library electronic databases. Search terms included every nomenclature variant for FAMM flap and iFAMM flap. A total of 373 articles were identified, and 20 articles were considered eligible for inclusion in the review. A total of 486 flaps were evaluated (350 FAMM and 136 i-FAMM flaps). In all studies, the primary outcome assessed was flap viability, collecting the rate of total and partial flap necrosis and then comparing FAMM to i-FAMM. Overall reported partial/total necrosis rate for FAMM flap was 9.7%, 1.4% as total and 8.3% as partial necrosis. Overall partial/total reported necrosis rate for iFAMM flaps was 2.2%, 1.5% as total and 0.7% as partial necrosis. FAMM flaps, both as classical or islanded variants, are an effective option for intraoral small/medium sized defect reconstruction. Outcomes from the present review show a higher partial/total survival rate when this flap is harvested as islanded flap.