To fix a door dent in a car you will need a kit for door dings, dry ice, hairdryer and air duster. You can try the dry ice to repair the door dent in your car. You will place the dry ice into the middle of the dent. You should have on some form of safety gloves in order to use the dry ice. You will leave the ice on there for about thirty to sixty seconds. This may pop out the dent. You can use .