This study is a prospective observational study conducted over two years from December 2020 to March 2023 at the Department of Plastic and Reconstructive Surgery.

To evaluate the outcomes of delayed reconstruction in patients with maxillectomy defects post-COVID-19 associated mucormycosis, focusing on safety, morbidity, and aesthetic results.

Fifty patients with post-COVID-19 mucormycosis and maxillectomy defects without skin involvement were included. These patients underwent radical debridement and were treated with Amphotericin B followed by Posaconazole therapy until clinical and radiological resolution of the disease. Reconstruction was performed after a minimum of six months post-maxillectomy. Flaps used for reconstruction included the radial forearm free flap (RAFF), anterolateral thigh flap (ALT), and free fibula osteomyocutaneous flap, planned using a 3D-printed model. Follow-up was conducted weekly for the first month and monthly for the next two months, with semiannual visits thereafter.

Of the 50 patients, 42 % were male, and 58 % were female, with a mean age of 43 ± 8.75 years. Most patients (88 %) were diabetic. Maxillectomy defects were categorized as type IIA, IIB, IIIA, IIIB, and IV based on the Cordeiro classification. Four flaps (8 %) required re-exploration, with three salvaged. Complications included marginal flap necrosis (4 %) and oro-nasal fistula (2 %). The average hospital stay was six days, extended to ten days for re-explored cases. Flap dimensions varied with the largest being 62 cm² for the free fibula flap.

Delayed reconstruction using free flaps in patients with post-COVID-19 mucormycosis maxillectomy defects without skin involvement is a safe approach with minimal morbidity. This method allows confirmation of disease resolution before major reconstructive surgery, resulting in excellent aesthetic and functional outcomes.