Thankfully now, we have modern toothbrushes and floss to protect our pearly whites, but in ancient times, people chewed on twigs to clean their teeth, then scraped the surfaces with the frayed end.

值得庆幸的是， 现在我们有了现代牙刷和牙线来保护我们珍珠般的洁白牙齿，但在古代，人们咀嚼树枝来清洁牙齿，然后用磨损的一端刮擦表面。