The damaged leaves probably wont look better, but Im sure that new leaves will grow soon! They love water and lots of warm weather and sunshine. But if they were growing indoors all winter long, they will need to get used to living outside so some wind protection and shade will be neccesary for at least a week or 2.
Good luck!
-Alex

I started my mango tree in March and it had at least 5 hours of direct sun per day at that time and when was rainy or cloudy I used to put it on my 150w hps 24 hours per day.Now, it has 7-8 hours of direct sunlight per day outside with temperatures between 25-32 degrees, but the dead leaves have not grow back and no new leaves have grow from the top.