Apollonia was an elderly deaconess of Alexandria — the principal Christian intellectual center of Roman Egypt — when the persecution of Decius broke out in 249. A mob seized her, beat her, knocked out all her teeth, and gathered a great pyre outside the city, threatening to burn her alive unless she sacrificed.
Asking a moment to consider, she went forward of her own will and threw herself into the fire — preferring martyrdom to apostasy. The historian Dionysius of Alexandria, in a letter preserved by Eusebius (HE 6.41), gave the eyewitness account that has shaped her cult for seventeen centuries.
From the medieval period her patronage of dentistry was universal — every Catholic dentist's shop traditionally bore her image. She is invoked against toothache; pilgrims with mouth diseases have come to shrines in her name from Salzburg to Sicily.