I just ran across this on the web. I can't vouch for all of the advice here, but it seems pretty clear that smiling and laughing are two wonderful ways to improve your health and well-being. Orthodontic treatment is not necessary to smile - you should show off your smile regardless. Your smile will make you and those around you happier and healthier. What could be better?
http://articles.mercola.com/sites/articles/archive/2003/10/11/laugh-smile-part-two.aspx