If it's only the chainring, I used a wrench to straighten one of mine. Slowly turn the crank and use the wrench to pull the chainring straight. Don't try to do it all in one pass. I think I did four or five passes to pull out a 1/8 to 1/4 inch bend on a mountain bike chainring that took a good hit. If you can take off the chainring it's easier to do with a hammer and a flat concrete surface. Look for cracks and replace it if needed.