Hadithcore
Riyad as-Salihin, 1201

Abu Musa Al-Ash'ari (May Allah be pleased with him) reported:

I came to the Prophet (ﷺ) once and noticed the tip of Miswak (tooth-stick) on his tongue. <b>[Al-Bukhari and Muslim]</b>.

وعن أبي موسى الأشعري، رضي الله عنه، قال‏:‏ دخلت على النبي صلى الله عليه وسلم، وطرف السواك على لسانه‏.‏ ‏(‏‏(‏متفق عليه‏)‏‏)‏ ‏.‏ وهذا لفظ مسلم‏.‏

References1 variant
In-Book Reference
Book 8, Hadith 211
Sharh · explanationclick to expand
<b>Guidance from the Hadiths:</b><br> The preceding Hadiths speak about the merit of using the tooth-stick, the recommended times for doing so, and the manner of using the tooth-stick. They include the following guidance:<br> 1) The Prophet (may Allah’s peace and blessings be upon him) stressed the merit of using the tooth-stick upon ablution, prayer, Qiyām al-Layl (voluntary night prayer), and entering one’s house, which indicates that using the tooth-stick is a confirmed Sunnah.<br> 2) Islam has perfect guidance, as it calls for purification and cleanliness, including the need to keep one’s mouth and teeth good-smelling, especially when meeting people.<br> 3) In using the tooth-stick, the Prophet (may Allah’s peace and blessings be upon him) would rub the teeth and pass the stick over the tip of the tongue in order to achieve the intended cleanliness of the mouth.<br> 4) The Prophet (may Allah’s peace and blessings be upon him) had perfect manners in dealing with his family, as the first thing he would do upon entering the house was to use the tooth-stick, thus removing any possible bad smell.<br> 5) It is permissible to inquire about the conditions and manners of righteous people inside their homes so as to follow their example in goodness and worship.