I always think it's really cute when people match their braces to their cosplay! It's your decision, purple and black would look very cute
I have braces too but I get them off before the next con...
Tomie (Junji Ito's Tomie) 100%
Madoka Kaname (Puella Magi Madoka Magica) 30% (working on skirt)
Kiki (Kiki's Delivery Service) 80% (shoes, broom, and bag)
Annie (Attack on Titan) 0% (planning)
Avanna (VOCALOID3) 0% (not even thinking about)