Hadith 3:87
Shuraih b. Hani’ said that he asked ‘A'isha what God’s messenger did first when he entered his house, and she replied that he used the tooth-stick. Muslim transmitted it.
وَعَن شُرَيْح بن هَانِئ قَالَ: سَأَلْتُ عَائِشَةَ: بِأَيِّ شَيْءٍ كَانَ يَبْدَأُ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ إِذَا دخل بَيته؟ قَالَت: بِالسِّوَاكِ. رَوَاهُ مُسلم
Original Reference: Mishkat al-Masabih 377