Al-Kāfi - Volume 3 > Brushing One’s Teeth
Hadith #2

2ـ عِدَّةٌ مِنْ أَصْحَابِنَا عَنْ أَحْمَدَ بْنِ مُحَمَّدٍ عَنِ ابْنِ مَحْبُوبٍ عَنْ يُونُسَ بْنِ يَعْقُوبَ عَنْ أَبِي أُسَامَةَ عَنْ أَبِي عَبْدِ الله (عَلَيْهِ الْسَّلام) قَالَ مِنْ سُنَنِ الْمُرْسَلِينَ السِّوَاكُ.

2. A number of our people have narrated from Ahmad ibn Muhammad from ibn Mahbub from Yunus ibn Ya’qub from abu ‘Usamah who has said the following: “Abu ‘Abd Allah, ‘Alayhi al-Salam, has said, ‘Brushing one’s teeth is of the traditions of the messengers (of Allah).”