There was once a famous English bass/baritone who was singing with the Halifax (Yorkshire) Choral Society in their annual performance of Handel's Messiah.

At the height of one of his cadenzas, his false teeth flew from his open mouth. Without missing a note, he caught the flying dentures, finished the aria, turned around, popped them back in and continued. Collapse of audience.

Possibly apocryphal, but my father-in-law told the story often.