noun ダウンロード 🔗共有 象牙質 The hard, dense calcareous material that makes up the bulk of a tooth Examples : "The dentist explained that the cavity had reached the dentine, which is why my tooth was so sensitive. " 歯医者は、虫歯が象牙質に達したため、歯がとても敏感になったと説明しました。 anatomy material body physiology medicine AIとチャット語彙ゲーム読解練習