Wa alaykum as salaam.
First of all, Muslims use siwaak because it is the sunnah of the Prophet (Allah’s peace and blessings be upon him). In a hadith, the Prophet said, ” if not that I would make it difficult for my ummah, I would have commanded them to use siwaak at the time of every salah”. Because the Prophet (Allah’s peace and blessings be upon him) is a prophet of mercy, he decided not to make it compulsory on us. He recommends that we should make things easy for people and not to create difficulty (yassiruu wa laa ta’assiruu).
As for the benefits, they are too numerous to mention but I will mention five here in shaa Allah.
One, you get reward for acting on the sunnah of the best of mankind (Allah’s peace and blessings be upon him).
Two, it helps to clean the teeth properly.
Three, it makes your gum strong and teeth free from decay and cavities.
Four, it keeps the mouth fresh and away from bad smell.
Five, it helps in good speech.
In addition to this Prophetic hadith states that a salat with siwak has the merit of 70 without. Narrated from the mother of the believers `A’isha (Allah be well-pleased with her) by Imam Ahmad in the Musnad, Ibn Khuzayma in his Sahih, al-Bazzar, al-Hakim, and others. Mulla `Ali al-Qari in his monograph Ma`rifat al-Nussak fi Ma`rifat al-Siwak said its multiple chains raise it to the rank of fair (hasan). Allah have mercy on all of them.
It doesn’t matter if you apply siwaak to it or not. The siwaak itself is the most important thing. And the best of siwaak to be used is the arak (Arabic name) tree.
It should not be shorter than your fist length. This is the recommended size.
Wa Allahu ‘alam.
for a more detailed discussion please refer to the following article on this website: