Restore all DNS settings from backup

I did a Set Zone Time To Live (TTL) yesterday to all the sites in dns.. This was an error as I just meant to do them for one server. I let it run and figured I could change it back after. It appears to have messed up and removed the default a record and www. records for many many accounts. I have a weekly backup that will still be correct. How do I restore from that backup to all accounts? I'll need to do it on three servers to be sure all are correct.