Abstract
Ameloblastoma is a rare odontogenic tumour that develops from the epithelial remains of the dental lamina. It is a benign but locally aggressive neoplasm that typically manifests as slow-growing tumours in the jaw, with posterior maxilla ameloblastoma being the rarer occurrence compared to mandibular ameloblastoma. This case report is about a 46-year-old Malay man who presented with a two-month history of left palatal and cheek swelling, along with symptoms such as left eye blurring, nasal block, and dysphagia. Imaging revealed a massive cystic lesion in the left maxillary sinus, which was diagnosed as a multicystic ameloblastoma after biopsy. The patient underwent surgical resection with a partial maxillectomy and was treated postoperatively with antibiotics, steroids, and regular follow-up appointments. The histopathological examination confirmed the diagnosis, and the patient was given a dental obturator to cover the defect intraorally. He is currently under annual surveillance with no signs or symptoms of recurrence.