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Updated: May 10, 2026

Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children
Published on: September 11, 2018
A foreign body in disguise
1Department of Public and Child Dental Health, Trinity College Dublin, Dublin Dental University Hospital, Lincoln Place, Dublin 2, Ireland, rona.leith@dental.tcd.ie.
Background:
Young children habitually place objects in their mouths to discover and learn about the world and it is considered a normal stage of early childhood development. Ingestion and aspiration of foreign objects predominantly occurs in preschool toddlers with a peak incidence at age three years, and can have serious consequences.
Case Report:
A 2-year-old boy presented to the Dublin Dental University Hospital with a tooth-coloured mass tightly adherent to a lower primary incisor. The lesion surrounded the cervical third of the crown on the lower right primary central incisor and extended subgingivally. The tooth was mobile but with minimal inflammation.
Treatment:
The tooth was subsequently extracted under general anaesthesia to reveal that the mass was in fact a foreign body, although this was originally thought unlikely as a cause.
Follow-Up:
The patient underwent an unremarkable recovery.
Conclusion:
The case of a foreign body disguised as a tooth-like abnormality was only identified under general anaesthesia, and even then it was impossible to prise the object from the tooth in situ. Misdiagnosis of impacted foreign bodies in young children presents complicated diagnostic problems.
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