There is reinfection of the teeth in question.
Causes-
1. Poor oral hygiene /
2. New caries formation with the tooth in question /
3. Incomplete treatment /
4.saliva contamination from the the defective restoration or crown /
Next Steps
visit dentist / pedodontist for further clinical examination, & treatment. Don't worry, we as a dentist are following proper precautions for covid 19.
Health Tips
maintenance of oral hygiene is a very important step. ask child to follow proper brushing technique with fluoride containing toothpaste in a pea size amount only twice daily on a regular basis.
Thanks!