Narrated 'Amir bin Rabi'a (R.A)"I saw the
Prophet (Sallallahu alaihi
Wasallam) cleaning his teeth
During ablution with Siwak
While he was fasting so many Times as I can't count.
" And narrated Abu Huraira,
"The Prophet (Sallallahu
alaihi wasallam) said, 'But for My fear that it would be hard
For my followers,
I would have ordered them to
clean their teeth with Siwak
on every performance of
ablution.
" Aisha Radi Allahu Anha
said, "The Prophet Sallallahu
Alaihi Wasallam said, "It (i.e.
Siwak) is a purification for the
Mouth and it is a way of
Seeking Allah's pleasures..
{Sahih Bukhari, Vol 3, Book 31, No. 154}