Abstract
We treated a 2-year-11-month-old Japanese boy with a gingival lesion including supernumerary tooth germ-like tissues. The initial physical examination found a 10×5×5 mm red sessile nodule in the lingual mucosa of the left first deciduous molar region of the mandible. The lesion showed no erosion, ulcer, or inflammatory signs, and X-ray imaging revealed no destructive findings in the deciduous teeth, tooth germs of the permanent successors, or bone. Based on these features, we suspected epulis and surgically excised the nodule.A microscopic examination of the excised specimen showed well-circumscribed dental germ-like structures in the submucosal layer, which were composed of undifferentiated mesenchyme of the dental papilla surrounded by columnar cells resembling pre-ameloblasts. No enamel or dentin formation was detected. These findings were most suggestive of supernumerary tooth germs. A peripheral developing odontoma was also considered a possibility, though a definitive diagnosis could not be made due to lack of enamel or dentin formation.The postoperative course was satisfactory and there was no recurrence of the lesion at a 4-year follow-up examination.
