In some countries, healthcare has nothing to do with “insurance”.
European healthcare is run very differently across the continent. 'Insurance' can mean a [state] social insurance institute that the doctor must bill. Some countries would employ the doctor directly as part of a nationalised health system. Some places it might be the municipality or city that would then get some subsidy from central government. Some it is a mix of all of this. 'Free' healthcare might actually mean a few hundred Euros, or literally nothing.
Later I requested the clinic to share the x-ray with me and consulted with another pediatric dentist from another EU country. His assessment was completely different, and recommended very minimal intervention.