My guess would be probably not. Not to that extent. At least for an adult.
@sailor87 what if someone has similiar face structure but due to mouthbreathing his face didn't develop right and he didnt reach his genetic potential as nature intended it to be, is it possible to reach your full potential and grow it the way it must look?
Its impossible to say. Depends on alot of unknowns, some people seems to be getting great results, but they are few and far between.
I would say go for it, what is there to loose? The ones who seem to get the best results are hard mewing, so that would be my best bet.
I doubt that. For that look you need a low gonial angle, like Dr Mike's