Makes perfect sense to me, defend your home from intruders and get those teeth pearly white at the same time.
![laugh :lol](http://www.thebore.com/forum/Smileys/default/laugh.gif)
As if Japanese are concerned about oral hygiene! Ha!
In actuality, most younger people are concerned about their teeth, and braces are becoming more commonplace. However, the older generation have teeth like a train wreck, and the abundance of metallic dental work going into them look like the rails and railroad spikes at the accident site.