Is it all right to sleep with my dentures in?

As a rule you should take dentures out when you sleep. Your gums need 6 to 8 hours a day free from the pressure of the denture for blood circulation to recover, and sleeping with them in makes gum inflammation (denture stomatitis) and fungal infection more likely. A denture that dries out will warp, so store it in cool water or a denture solution. However, there are exceptions - for example when the clinic has advised wearing it to control bleeding and swelling after an extraction or other surgery - so please confirm what applies in your case at your visit.