I had a problem with my wisdom teeth and took it out in Japan.  If you have a valid insurance, the cost will be 1,500 yen for taking it out and medicine will cost you 500 yen.  Not that expensive.  Also, I would not buy an insurance from Korea.  If you are not getting paid in Japan, all you need to pay is around 2,000 yen a month and coverage is more extensive.

They are in service even in Saturdays.  I recommend you to visit on Monday, when they are not busy. The dentist is 10 minutes walk from my dorm.


 

The drug store. Once you get your prescription from the dentist, you bring it to here or other drug store to get your medicine. This one is near my dorm.

Inside of the drug house. You need to bring your insurance card.