Have a regular dental appointments for your child
It might seem too soon for children under 5 to go to the doctor, but 40% of children, from the ages 2 to 5, have cavities. And, even with these stats, some pediatricians do not check for a child's oral health. Any cavities in baby teeth must be treated before any permanent teeth come in. Baby teeth are placeholders, and losing any of them permanently can cause issues with how your teeth align in the future. If this happens, children would need to have braces in order to correct it.
A quick visit might seem worrying but it'll be quick. A dentist will see if your child has any plaque along their teeth or top gum, which is a huge sign of mutans. The dentist would also be able to perform a culture to measure the bacteria.