I recommend Seon Dental Hospital in Jung-gu, Daejeon.

Seon Dental Clinic is a foundation belonging to a general hospital called Seon Hospital. Because the dental clinic is so large, it operates a whole building as a dental clinic.

As Seon Hospital grows, so does Seon Dental Clinic. As it grows, the skills and level of its doctors improve, to the point where there's a long wait.