Do you have a reference for that? I'm from Sweden and I can definitely say preventive dental care is a huge thing here. I felt your statement sounded weird so I googled around. DMFT seems to be one index used to rank countries oral health, which is produced by WHO. In that ranking several European countries beat or sit at US levels. Do you only mean eastern Europe?
This links to OECDs compilation of WHOs data, was easier to get the overview from imo: https://www.oecd-ilibrary.org/docserver/health_glance-2009-1...