Objective: KCOTs are characterized by an aggressive behaviour with a relatively high recurrence rate, especially if they are associated with syndromes. Treatment of KCOTs include marsupialization, saucerization. Methods: A complete history was taken and clinical examination followed by complete enucleation with sulcular flap from 12 region until 18 regions was performed. The diagnosis was maxillary dentigerous cyst based on histopathological result after the operationgion until 18 regions was performed. The diagnosis was maxillary dentigerous cyst based on histopathological result after the operation. Results: The medical history was not significant and patient was in a generally good condition with no fever, nausea, pain, or difficulty in breathing. Extra oral examination showed facial asymmetry and visible lump in the right region of the maxilla. Conclusion: The diagnosis of maxillary KCOT expanding to maxillary sinus can be achieved with adequate datas; history, clinical, and histopathological examinations. Careful surgical approach and proper treatment decision is crucial to avoid complications according to individual case of each patient, especially in children. © 2023 JDMFS.