Dentigerous cysts are the most common bony lesions of the jaws in children. It is one of the most prevalent types of odontogenic cysts associated with an erupted or developing tooth. This paper describes a case in which a conservative enucleation surgery of dentigerous cyst is made to save unerupted permanent tooth. Seen the great capacity to regenerate the bony structures at the children, conservative surgery should be tempted in dentigerous cysts in report with open apices teeth.