Thanks for the downvote, define other problems:

- not brushing your teeth can lead to caries, which in turn can cause your teeth to degrade, gum trouble and can even cause you to literally lose your teeth

- not washing can have dermatological implications, including fungi and infections

Between the toothbrush, running water and penicillin we've probably increased the average lifespan of humans by a measurable amount.

Gum disease can also lead to heart disease and stroke.

http://www.perio.org/consumer/mbc.heart.htm