Credit scores aren't that deterministic. There are lots of factors that go into your score, and it's impossible to be certain how a single action (other than missing a payment) will affect your credit.
In general, though, opening a new account and maxing it out will reduce your credit score, but it will go back up over time so long as you pay down the balance and do not miss any payments. It may no to go back completely, but a good payment history, which is the main factor in your credit score, should have a positive impact.
However, I'd make sure you understand the reason for "needing a 0% loan". Are you spending more than you make? If you have an unexpected expense like a medical bill - can you negotiate with the provider for a payment plan or a reduction in the total bill? Do you have a realistic plan to pay everything back before the intro rate runs out that doesn't require any lucky breaks?
It's very important to have a firm control over your finances before trying to use credit cards as "loans". It doesn't take much as all to go from "free money" (or miles) to crushing credit card debt.