Dentigerous cysts are rarely reported in young children. They are usually asymptomatic and only identified when becoming significantly large. Treatment by enucleation may damage structures like the inferior alveolar nerve, maxillary sinus, or permanent teeth, thus reducing the child's quality of life. Therefore, conservative surgical treatment such as decompression is indicated. This case report describes the treatment and subsequent complete regression of an inflammatory dentigerous cyst based on the decompression method using a customized surgical tube in a 10-year-old girl. The innervation was preserved, and permanent teeth erupted.