Not really. There's a number of differences because TimesTen "knows" that it only is a in-memoory database.
Take a look here at the architecture
https://docs.oracle.com/cd/E11882_01/timesten.112/e21631/arch.htm#TTCIN156 in particular, how we can cache related tables together, and also that we can link apps to have direct access to the shared memory of a timesten database as opposed to always having to talk a separate process to do the data access.
Its because of this bespoke nature, you can insane in-mem performance levels out of timesten (ie, tens of millions of transactions per second)
This is not to say that using all the memory for your conventional database wont also improve things - it will.