VOA慢速英语:Days of Painful Tooth Repair May Be Over

dental cavity – n. a small hole formed in a tooth by decay

enamel – n. the very hard outer layer of a tooth

drill – n. a tool used for making holes in hard substances

injection – n. the act or process of forcing a liquid medicine or drug into someone or something by using a special needle

filling ­– n. material that is used to fill something : example: a filling for a tooth

calcium – n. a substance that is found in most plants and animals and that is especially important in people for strong healthy teeth and bones

phosphate – n. chemistry : a salt or compound that has phosphorus in it and that is used especially in products (called fertilizers) that help plants grow

fluoride – n. a chemical that is sometimes added to drinking water and toothpaste to help keep teeth healthy