I got braces again for the second time, how long do I need them for? (photos)

I got braces for 3 years, and they got off when i was 15, for reverse bite. I'm 16 now, and i had to get them again because my upper canines were very vampire like, and some lower teeth were going into reverse bite again. Now how long will it take to correct my teeth into a perfect smile? I got braces again yesterday, my dentist said it might take 6 months