Unfortunately, none that I know of.
I too had dust under my screen, so a day or two before my 30 Days I took it to verizon for an exchange for a new one, and the guy told me that this is cosmetic damage, and not manufacturer error, so he could give me a Like New model.
I kindly told him, **** that. I went off telling him how this is most definitely a manufacturer default, dust should never be able to get UNDER the screen, because that's impossible to clean and it's basically like I had 5 dead pixels, cause I couldn't see them! Now before I get *****ed at for complaining after he offered a refurb, the damn refurb looked TERRIBLE. There were around 4 paint chips and the bezel around the scree was terribly scratched up.
Anyhow, I got the rep to agree and give me a brand new one, but he said he's going to note my account that I couldn't exchange for a new one if it was due to dust under the screen, fine with me, my 30 days was up in 2 days.
But I have yet to have the problem repeat, so I'm guessing maybe there are a lot of bad phones without proper sealing, so I would say exchange it, especially if you're in your 30 days.