This case series study aimed to find out if a new surgical technique that preserves the sinus membrane during upper jaw removal can help patients regenerate bone and recover function better after surgery. The study included two female patients with jaw tumors who were not suitable for or did not want complex reconstruction with tissue flaps. The main questions the study tried to answer were:

Can the preserved sinus membrane help new bone grow spontaneously in the jaw defect area after surgery? Can this new method reduce common complications seen with traditional surgery, such as oronasal fistula and empty nose syndrome? How well can patients recover in terms of chewing, swallowing, speech, and quality of life after the procedure?

In the study, during surgery, the surgeon carefully separated and preserved the sinus membrane from the bone that needed to be removed. After surgery, patients were followed with regular CT scans to check new bone growth. They also underwent tests to measure chewing force, swallowing ability, speech function, and quality of life to evaluate the long-term outcomes of this technique.

Inclusion Criteria:

• Maxillary lesions requiring resection of the jaw as diagnosed by imaging (CT) and pathology;
• CT shows the lesion only invades the maxilla without involving the maxillary sinus cavity;
• No nasal septum within the maxillary sinus cavity, with an intact and smooth sinus floor bone wall;
• No distant metastatic malignant tumors;
• American Society of Anesthesiologists (ASA) classification I-III, able to tolerate general anesthesia.

Exclusion Criteria:

• Lesions invading the maxillary sinus mucosa;
• Presence of septa or severe inflammation in the maxillary sinus;
• Previous history of head and neck radiotherapy;
• Coexisting immune system diseases or metabolic bone diseases;
• Pregnancy or breastfeeding;
• Any surgical contraindications;
• Mental illness or inability to comply with follow-up.