Braces nightmare

Many of my teenage students struggle when they first get their braces fitted. Often they can't get a note at all and always there is an impairment of their tone. I've researched many remedies including the Wikipedia article (who knew?)
http://m.wikihow.com/Play-a-Flute-with-Braces

But sadly the advice doesn't always work. It seems the only fail safe option is to experiment. Long notes in front a mirror to hear the lack of clarity and minor adjustments to create a clearer sound. It's important not to just keep playing if the tone is suffering but rather keep readjusting until the new position becomes ingrained. It is sad to hear the initial difference a brace makes but over time your beautiful tone will return.  Please feel free to offer any advice and techniques you have found beneficial x