Breathing through the mouth while sleeping is one of the major causes of snoring.  As early as 1900, American inventors have patented devices that strap the mouth in shut while sleeping.  Earlier versions were made of wire, cloth or leather. The author tried a modern version of the chin strap made with stretchy vinyl and velcro.  The chin strap made him look like Hannibal Lecter, he couldn’t speak at night, he jaw ached in the morning — and he still snored.