Hello,

Welcome to the Forum.

According to your clinical symptoms, I suppose your child might have developed ulceration, or a canker sore this can be due to any physical or chemical trauma, nutritional deficiency.
Also, check whether the associated teeth are carious or not, the lesion can also be because of abscess drained by infected tooth, if tooth related the infected tooth need to be treated.
Can also be due to eruption of permanent incisors, to rule out this you need to visit the Dentist and get the checkup done.
Take lukewarm saline rinses to give soothing effect.
Take antiseptic mouthwash rinses like Chlorhexidine twice daily.
Apply Dologel oral ointment topically over the affected area.
Maintain a good oral hygiene of your child.


Hope you find this answer helpful! Feel free to ask any other queries.


Take care!
Dr Qazi.

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