HUGE scratches on 3DS touchscreen. How do I hide/fix this?

My 3DS has scratches all over the middle of the bottom screen. It's really bothering me because it feels different and makes a different sound when I run the stylus over them. Also, all the games I play use the touchscreen over 50% of the time. I don't get how this happened because I have always been pretty careful not to press to hard when playing on my 3DS, and I DEFINITELY would have remembered if I had made those scratches. And when I was younger I pressed REALLY hard on my DSi, yet my DSi only has ONE big/medium scratch that you can barely see while the system is turned on! I have already tried that toothpaste trick and it did nothing. I also tried putting Vaseline over the scratches which covers them for a bit but then it rubs off and I'm back to square one. Buying a new system isn't an option because I already have purchases on my 3DS that can't be transferred. How can I fix this, or at LEAST make the scratches less noticeable? I'd prefer a permanent solution rather than something like the Vaseline thing also.