What does the Abhidhamma say about impermanence? I understand the state of changing (impermanence) mentioned in Buddhism, but I have also heard that another more complex version (of the doctrine of impermanence) exists in the Abhidhamma.

I would also like to know about how impermanence work when it comes to the physical body?

I would be thankful if someone could point to a few sources to learn about it, and maybe summarize it in an answer.

Please mention if I can use this knowledge to my personal practice, and if it is possible then how to do that.
i meant the change that happens in milliseconds


I guess the following is what you heard?

Theravada abiddhamma formalizes "an experience" (thought process) in 17 discrete moments ("thought moments", cittakkhanas), or 17 cittas. An example from Abhidhammatha Sangaha ( Chap. IV - Compendium of the cognitive process):



While this is not a presentation on impermanence per se (nor it's about physical body) it's is an abbhidhamma topic that attempts to discriminate something in its detail. 

It's not clear how long such a process or any of it's steps last; some say it's much much less than a millisecond.