My question is; what exactly borders it?
I feel your pain...I had an expander in for almost 7 months. It was a nightmare. The bottom line is that no matter what you eat, stuff will get stuck up there because its not touching the roof of your mouth. The best thing I can tell you is to stay away from food with a bread-like consistency, like crackers and cookies; those are the worst. Keep eating foods that come apart really easily. Stay away from stringy stuff also. Good luck!