From Sahih Muslim (Hadith 1798):
Ibn `Abbas reported:I slept one night in the house of Maimuna when the Messenger of Allah (ﷺ) was there, with a view to seeing the prayer of the Messenger of Allah (ﷺ) at night. The Apostle of Allah (ﷺ) entered into conversation with his wife for a short while, and then went to sleep, and the rest of the hadith is the same and in it mention is made of: "He then got up, performed ablution and brushed his teeth
Reference: Muslim 1798