Numerical aberrations of permanent dentition and dystopic tooth eruption are part of the phenotype of the tumor predisposition syndrome neurofibromatosis type 1 (NF1). In these cases, surplus tooth germs usually develop in the alveolar processes of the jaw. This report attests to the dystopic development of a dysplastic supernumerary tooth in NF1 arising outside the jaw. The 8-year-old male patient developed a microdont outside the bone and above the occlusal plane of the retained maxillary right second molar. The supernumerary tooth was completely embedded in oral soft tissue. Hyperplastic oral soft tissue in the molar region and microdont were excised. Specimen of the mucosa surrounding the teeth was interspersed with diffuse and plexiform neurofibroma. The retained upper right first molar emerged spontaneously within a few months after surgery. The upper right second molar did not change position. Odontogenesis can take place within tumorous oral mucosa in NF1. Surgical removal of the tumorous mucous membrane facilitates tooth eruption in some cases.