Hi!
It's possible, but:
1. It won't be inexpensive, as the entire top half of the system needs to be replaced. Prices vary on eBay depending on the type of the screen: https://www.ebay.com/sch/15-6-Screens-and-LCD-Panels-for-Dell-XPS/31569/bn_716455/i.html?_fsrp=1
2. It WILL void your warranty to replace the screen and as far as I know dead pixels on a screen should be replaceable under warranty, because you couldn't possibly inflict that sort of damage yourself, but don't quote me on that...
I found this Youtube tutorial on how to take it apart, to put it back together do everything in reverse order:
https://www.youtube.com/watch?v=ZYKwr3hhDh8