Hello
1) If left untreated then it might spread.
2)For multiple cavities get appropriate treatment done based on severity
3)If pedodontist has evaluated with x ray , if there is frequent infection even after treatment then kindly proceed with extraction as suggested by your doctor, followed by space maintainer for back tooth
Next Steps
Kindly attach pic for better suggestions
Health Tips
Advised to use Fluoridated toothpaste prescription by dentist
Advised to make child brush twice daily, rinse after each meal and after snacking
Hope your question