What they're feeling for is if the tooth is really hard, then it's healthy, but if it's kind of soft and sticky, that's a signal that the enamel is starting to decay.
치과 의사들이 찾는 것은 이가 진짜 딱딱하면 건강한 것이고 좀 물렁하고 끈적거리면 에나멜이 썩어간다는 신호입니다.