The Dental community will suggest you remove them at night to maintain gum tissue health:
I believe if you check with your husbands Dentist or Prosthdontist, they will recommend that the dentures be removed for at least 8 hours per day out of every 24 hr. period. Normally the best time to do that is during sleep.
The reason for removing them is to give the gum tissue a "breather" from the constant pressure placed on the gum tissue by the denture. Constant pressure by the denture can cause the gum tissue to shrink. When that happens the denture becomes loose and moves around creating sores. By removing them at night you restore normal blood flow to the tissue, restored blood flow keeps the gum tissue healthy where they can continue to support the denture. Keep in mind that is the only thing supporting the dentures is the gum tissue between the denture and the remaining bone.
Now toss in OSA and Dentures into the mix:
While there is very little information on this, there was a recent study done by UCLA School of Denistry on this very topic, it suggests that fewer apnea were seen when the dentures remained in the mouth during sleep. For obvious reasons, when the dentures are worn the dentures support the lip and face tissue which eliminates that "sunken face" syndrome associated with tooth loss and age. This gives the mask some place to seal against. With the dentures out even the nasal mask interface will have difficulty sealing with the loss of the upper teeth. Wearing dentures restores that natural face shape and makes it easier to seal.
I'll try and find the study and append them to this thread. I actually know several of the Professors at UCLA and had discussions with them on this topic, my daughter is a Dentist and graduated from UCLA, I'll find out from her which study it was.
You have to decide which is the lesser of the two evils; Do you remove the dentures so your gum tissue remains healthy? or do you wear them and stop the effects of untreated OSA? Obviously you try to do both. Gum loss won't kill you, OSA can. Since eating is a vital function you need to maintain gum heath to support the dentures, some options might be:
1. Remove the dentures during the day
, he needs to remove them at least 4-6 hours, 4 hours is better than 0 hours, gum tissue needs to have blood supply restored. Dentures need that gum tissue support so they continue to fit properly. Loss of the underlying bone and gum tissue is the reason dentures no longer fit.
2. Consider having 2 or more implants placed to support the dentures. Implants act like teeth and have been found by Noble Biocare to reduce bone loss even if there is only 2. Implants help support the pressure of the denture especially with the mandible or lower denture. Having just 2 implants placed will keep the lower denture from floppying around on the ridge and restore quality of life. If your husbands lower ridge has regressed he should see his dentist about getting a couple implants, his denture will ride on those be better supported and slow bone loss.
3. While I hate them, use a pillow style mask interface like a Swift. This interface type doesn't rely on facial structure to maintain the seal. If he can use this type of interface (requires a heated hose if you sleep in a cool room).
4. If he wears his dentures at night so he can use a conventional nasal or Full Face mask he can do that, just remove the dentures during the daytime to give the gums a break. You need to do both.
Personally, I would see a Prosthdontist. Of course I am biased, but I'd look for one that graduated from or is a Professor at UCLA. They specialize in dentures and implants, the trick is finding one with lots of experience (old guy more likely to have it) and that also understands the perils of Obstructive Sleep apnea.
someday science will catch up to what I'm saying...