Repair rims. A parking damage to a rim or rims? You will have that soon. A moment of thoughtlessness and the rim is 'shaved'. And gdat applies entirely to light-alloy wheels.
Fortunately, there are nowadays companies that can optically and technically restore such a rim.
A rim that is really firmly over an edge, that can be dented.
The 'denting out' of such a steel or light-alloy rim is at least challenging, and only a job for professionals.
When squeezing the dent, it is possible - especially with light metals 
rims - material cracking caused by cold deformation. Such a fracture can usually be repaired with TIG welding.
After welding it is best when the rim goes on the lathe to be completely tightened again. Grinding away the weld almost always leaves visible traces.
After repairing the bumped rim, the rim only has a minimal deviation from the nominal dimensions.