Sagrethia theezans, dead or alive?
 

I bought a sagrethia theezans bonsai tree as a christmas present during early December. Unfortunately I neglected to water it for a period of about 2 weeks leading up to Christmas and it now looks like it is dead. I decided to keep the tree as it would have made an unatractive present in the state its in, and see if I can revive it!

Can anyone advise me on how to check if the tree is still alive or not. It still has all its leaves but they are all crisp and gradually falling off! I have been watering the tree regularlly for a couple of weeks now and it has shown no signs if improvement.

I really hope I can get this tree back to good health and then keep it for myself, any adivice would be greatly appreciated.
Thanks,
Jen.