http://www.youtube.com/watch?v=73x8q51zzwg maybe that video will help?

In Italiana, il dentista dice "aperti la tua bocca e dire 'ahhhhhhhhh'? Se si, questa come si pronuncia the "a" in "want". Per la "o" nella parola "won't", è necessario fare una  "o" con le tue labbra, come quando si dice "Coca Cola". In Italian, does the dentist say "open your mouth and say 'ahhhhhhhh'?' If so, this is how you pronounce the "a" in "want". For the "o" in the word "won't", it is necessary to make an "o" with your lips, like when you say "Coca Cola".