My daughter needs braces and the orthodontic will not perform without a ceph x-ray. is it absolutely necessary to have it done?

Yes: Your orthodontist will learn so much (s)he needs to know from taking it that is very worthwhile. I wonder why you are against taking it? There is no danger to your child. If she goes to the beach for an hour, she will get about the same amount of radiation from the sunshine as she gets from a Ceph. X-ray. It's very safe.

Blind: No Orthodontic Specialist will work blind. Without a low dose lateral skull x-ray the Orthodontist would have to guess at skeletal relationships and projected growth. If the Orthopedic Surgeon thought your child had a broken leg would you refuse an X-ray? Well, essentially your child has a broken face, the parts don't fit properly. Given the right information your Orthodontist can fix that.