"I said to 'Aishah: 'What did the Prophet (ﷺ) start with when he entered his house?' She said: 'The Siwak.'"
Sunan an-Nasa'i Book 1, Hadith 8
← Previous Hadith "Were it not that it would be too difficult for my Ummah, I would have commanded them to use the Siwak at (the time of) every Salah."

Sunan an-Nasa'i Book 1, Hadith 7 Next Hadith → "The Fitrah are five: Circumcision, removing the pubes, trimming the mustache, clipping the nails, and plucking the armpit hairs."

Sunan an-Nasa'i Book 1, Hadith 9