Draconian slave camps where people are forced to practice dentistry aren't actually necessary to address the issue; we can just look elsewhere and compare.

What virtually all advanced democracies have done is rather make a judgement about what kinds of fees are reasonable to pay for dental and medical services, and limit what the national health insurance system will pay to that.

Then see if anybody is willing to practice dentistry. They usually are.

(Also, in most, if not all, of these countries, dentists are free to charge any rate they wish for dental services, and if they can find enough people willing to pay those fees with their own money, instead of using the national health insurance system, that's fine, too. But that's typically not necessary, and hence not common.)