OK....I think you've tried just about everything I would have suggested!

It is reassuring that he is still having his night feeds though, that is something to hold on to. I am not sure what the advice would be re feeding at night and offering water during the day so I will leave that up to the experts.

The only other thing I can think of is to TRY (and I KNOW how difficult it would be) not to react at all when he bites. I know, it would be nearly impossible, but maybe it is the reaction he is getting that makes him keep biting? All three of mine have bitten during teething, but not persistently as you've described.

I'm sorry hun, I wish I had some better advice, but I will think on it and come back if I come up with anything. Have you called the ABA helpline?