There are certain positive aspects of living in Japan, including the fact that it's such a peaceful country -- you'll generally feel safe anywhere you go here. Japan is less blessed when comes to dental care, and gaijin living here love to complain about the dentists here. While Japanese dentists are good at fixing teeth, they're famous for making you come back dozens of times to finish your dental work, instead of getting it out of the way in a few visits. I once had some reconstruction work done on three teeth that took an incredible 18 months of twice-weekly visits, which was a huge waste of my time. I believe Japan's dentists take so long to work on teeth because of the way the National Insurance system is structured -- they're only allowed to charge a certain amount to the system each day, so they spread it out as much as they can.
Most gaijin are not fans of Japanese dentists.