Anon, dental insurance coverage here in the U.S. is also a sad state of affairs. Though the teeth are holistically integral to one's overall health, care, maintenance, repair and restoration of them have all been deliberately excluded from most vested health insurance pension plans.
The reason for this seems clear. The Powers That Be have designed a health care system with a built in huge gap which guarantees that an aging middle to lower middle class will suffer substantial health and economic costs due to the invariable deterioration of their teeth.
Are there any dental colleges or schools in Germany which provide first come, first served dental services to volunteers for class instruction? These exist in the U.S. but you have to look fir them. The service is free but you have to waive all rights and legal remedies available in a normal doctor-patient relationship.
Hope you find relief soon and just ignore that asshole on tge board,