Hadith 887
Narrated Abu Huraira: Allah's Apostle said, "If I had not found it hard for my followers or the people, I would have ordered them to clean their teeth with Siwak for every prayer."
Hadith 888
Narrated Anas: Allah's Apostle said, "I have told you repeatedly to use the Siwak. (The Prophet put emphasis on the use of the Siwak.)
Hadith 889
Narrated Hudhaifa: When the Prophet (p.b.u.h) got up at night (for the night prayer), he used to clean his mouth .