Abstract
A simple bone cyst of the jaw is rare in children younger than 10 years. Here, we present an unusual case in the mandible of a 7-year-old boy. A simple cyst was incidentally detected in the jaw during a radiographic examination for caries treatment at the age of 7. Panoramic radiograph findings revealed a broad radiolucent lesion area beneath the mandibular left second premolar, in which root formation was incomplete. Both marsupialization and a histopathological examination were performed under local anesthesia.Three months after the operation, the radiolucent lesion showed a size reduction tendency. Occlusal guidance was performed with a lateral expansion appliance to correct the maxillary space shortage and a removable space maintainer was applied to maintain the space of the unerupted mandibular premolars at 6 months after the operation. One year after the operation, the radiolucent lesion showed a gradual decrease and new bone was developed in the cyst. Nine years after the operation, there were no clinical or radiological signs of recurrence, though a small radiolucent area remained in the left mandibular region. Permanent dentition developed normally without abnormalities such as hypoplasia,delayed eruption, or malposition of the left premolar.Our experience indicates that early detection and treatment of a simple bone cyst in younger children can prevent developmental abnormalities of permanent teeth and lead to normal permanent dentition.
