A resounding hell yes! I'm still recovering so I'm not sure how my sleep has improved, but I'm now able to breathe much better, especially through my nose while my mouth is closed.
I mentioned it I think earlier, but I was never able to breathe through my nose completely. I've always had to supplement with some mouth breathing. I also did a sleep study because there have been a few times where I have woken up out of breath. The study revealed that my oxygen levels were below normal during REM resulting in my heart having to work harder (I think the lowest the oxygen level got was around 70%). Furthermore, I can tell my sleep was never effective since I tend to doze off while driving, etc. and just feeling tired generally. These issues I sort of just accepted until I started looking into jaw surgery for my recessed chin. I'm glad the surgery was able to address a lot of the underlying issues I had including jaw clicking, TMJ pain, and my teeth being worn down since my bite was terrible and my back molars never touched.