I just went through this with my 8 yr old, so I can answer some of this for you.
My 8 yr old had a cross bite and very crowded teeth. The orthodontist put him in top and bottom expanders for 6 mo. Basically, it "broke" his palate and made his mouth wider to fit the size of his teeth. This really widened his bite, gave more room in between his teeth, and caused a lot of them to loosen! Now he's had the expanders out, and he has a holding wire top and bottom - basically it's anchored to his molars and it's a wire running across the roof of his mouth or behind his front bottom teeth. That's to hold the progress they made so it doesn't move back. From what I was told, you can only do this until a certain age since then their palate hardens and it wouldn't work (or maybe not as fast?).
He's not ready for braces yet. They're wanting him to lose a couple more teeth first. Then he'll go into top and bottom braces.
To answer your husband's questions - my husband had the exact same question - it's done differently now than in before. Instead of pulling any teeth, the goal is to make their mouth be the same size as their teeth. My son will not have any teeth pulled since they made room. A benefit from not pulling teeth is that they're not scootching all your front teeth around to the sides of your mouth. I've also heard that if you have teeth pulled and they then shift them around, it can make your chin look different (???). What I think is that it's just the new way for braces. Back when, everyone got braces in high school. Now it's elementary. When our kids have kids, it'll be different. I do know of some people now still have teeth pulled, but the drs around here seem like they're trying to avoid it by doing these other things.
My other son has been told that he has plenty of room, so we're waiting on him to lose a couple more teeth, then it's on to braces for him.
I've also heard of different "phases" of braces. My neighbor's daughter has been in expanders, then 2 sets of braces. She's had something going on for almost 7 years! I specifically asked how many phases and how long. I don't want to be on the 7 yr plan!!!
Hope this was somewhat of a help. Good luck. The expanders weren't very much fun for me. I would suggest going to
Walmart and getting a cheap waterpik-type thing. You'll need it since food gets wedged in them and it's MUCH easier to squirt it out! The good thing is that kids are so resilient. It seemed to bother me much more than him!