eli5 why does putting toothpaste on scratched disks fix them?

Question

As the title says why does toothpaste fix disks

In: 2049

Answer 1

If you have scratched discs and have access to a buffing wheel, like a table mounted buffing wheel, use some jeweler’s polishing compound and the buffing wheel to restore the disc with relative ease. Most scratches on the polycarbonate surface are very superficial. Unfortunately, sometimes massive deep scratches can’t be corrected, but that’s usually not the case.

Used to work at a plastics manufacturer and their industrial use buffing wheel could polish a disc in just a few seconds.