It is said that private dental clinics are not allowed in downtown Shaoxing. The health bureau seems to refuse to issue a health permit. Is that so?

In terms of policies and regulations, it is definitely illegal to do so.

Individuals can also open dental clinics as long as they meet the statutory requirements and standards.

You can go to the government affairs hall of the Health Bureau to ask if you can and what information you need. If individuals can't do it, ask them why and according to what regulations or documents. If not, they won't do it for you. You can complain to the Commission for Discipline Inspection.