bind9 and ip expiration

The dns server is up and running.

Now i have to update the online ip dynamically.
When some lease time is over ip will change so i have to change it in my
bind configuration files. Is there a way to do this simple and fully
automatic ?. Or better, which way is the best :-)

Why not run with Static IPs for the host or am I missing the question? Then there is no changing of the bind files but one time to the static IP.....