“Ring-Like Mass” Surrounding the Cervix of a Primary Incisor. Report of a Challenging Case

BACKGROUND: Several lesions of diverse origin may be detected in the oral cavity of children, affecting the oral mucosa, jaws, or teeth. In equivocal cases, their clinicopathologic features may show considerable overlap with various entities. We present a case of a “ring-like” hard mass around the cervical area of a primary tooth in a child and discuss the diagnostic challenges. METHODS: A 2.5 year-old girl was presented by her mother for evaluation of a painless left first primary lower incisor lesion, first noticed 5 months ago. Medical history was unremarkable, while previous injury or other incident could not be recalled by the patient’s mother. Clinical examination and a periapical radiograph were performed. RESULTS: The clinical examination revealed a yellowish, non-removable, hard in consistency, cylindrical mass, completely surrounding the cervical area of the left first primary lower incisor. A periapical radiograph was performed, revealing a cylindrical radiopacity of mild intensity encasing the tooth cervix and a diagnosis of a foreign body inserted around the tooth was made. Regular follow-up appointments were attended for the next 4 years in which mild but progressive gingival recession, revealing a larger part of the ring-like structure was observed. At age of 6, the tooth was extracted and a cylindrical structure was detached from the tooth, confirming its nature as a foreign body. CONCLUSIONS: A foreign body surrounding the cervix of a tooth eventually becoming inseparable may cause a peculiar clinical and radiographic appearance and provoke diagnostic difficulties, especially in the lack of a relevant history.