I have a what feels like a small slit on the roof of my mouth. pretty much inline with my back teeth. it doesn't hurt, never noticed before!!?

Probably normal: If you notice this slit on your palate located in the center, it is a suture line between the bones of the hard palate. They can have a slight recess or slit and can also be raised. It is not abnormal to have some folds on the palate near the teeth which can feel like a deep line. Unless these areas get infected or irritated, they present little caution.

Normal: If the roof of your mouth has a high vault (deep concavity ) rather than being flatter, then this is likely normal anatomy. Check with your Dentist if needed to feel comfortable. Good Luck.