Crowding - Saggital & Cetlin Appliances?

[Skylines]

Hi all, I'm new and just got my top braces on a few days ago, and my bottom braces will be on in 6 months. I'm 18 and very new to orthodontics... I've never had braces or any other treatment before.
(We didn't have the money and my parents assumed my teeth were fine... but that's another story, I'm not here to place any blame, as my parents are fantastic :-)).

Anyhow...
I have moderate crowding, especially on the bottom teeth. I also have a slight overbite. My wisdoms were taken out 3 weeks ago.

My ortho has decided to use a sagittal appliance on top and a cetlin appliance on bottom. I've tried my best to research these appliances, but there have been limited results...
Has anyone (especially those over 18) had any GREAT outcomes with these appliances?
I've read that these appliances are mostly used on young children still developing, and being the worrywart that I am, I'm just a little apprehensive.
My orthodontist seems to know exactly what the best plan is, but I'd like to hear some personal stories or advice...

Thanks!
Sky