@Steve Goldberg can you suggest how can we restrict my account menu navigation based on the customer category?

As Kevin said above, it really is best to used roles and permissions, that is the recommend best practice. Is this infeasible?

thanks steve. but we're using one role for all customers. is there any other way to achieve it?

Well none of them will be best practice. So you could just read the customer's profile object and use jQuery to remove the links to the menu items