assuming that you can't live whole life without smiling, which i assume is a pretty safe assumption, i'd suggest you to be yourself and not worry about what girls or anyone else think. if someone doesn't like your smile, god help them; it's not your problem, it's theirs instead. and you are not 100% sure that girls don't like your smile, are you? so, stop making assumptions and being too conscious about your smile, just let your facial muscles do the job.

aba yo daat kasaiko ramro huncha kasaiko naramro daat doctor le jasto khatam daat lai pani ramro banaedina shakcha tesaile daat doctor ko ma jada ramro hola
lol @ bittertruth nice one hehehe

I am not an ugly Joe , I a average looking Nepaese guy in late 20s and yes, I too have the same problem like yours .... None of my smiling faced photos are good, so I either take it sideways or with poker face..... I

Luciky for me I have found a girl who accepted me what ever I look like. I may be the grumpy faced man, but I make everyone around me laugh and smile, and thats the key....

You do not need to impress every single chick you see and that wont happen to anyone.... you turn will come... some will definitely be impressed with your grumpy face and that "some" will be enough for you to have fun and select one for longer term....  Just keep making those people smile and laugh... they will be more impressed with that than how you look....

I found mine and has been happily married with her for nearly 5 years....

very true , gyan guru

If I were you, I would
either
heed what OutKast included  in their lyrics. "Now, what cooler than being cool? Ice cold!"
or
set up an appointment with an orthodontist TODAY

Looks are not as important to girls as you think. As long as you are properly groomed,that means good haircut, shaved and clothes it should suffice.
Try to be more interesting or become the alpha male in the group.

Read the "Game" by Neil strauss.
http://sajha.com/sajha/chat/smileys/m-happy.gif