The Messenger of Allah ﷺ said, "If it were not that I would place a hardship upon my community, I would have commanded them to use the tooth-stick with every ablution."
قال رسول الله ﷺ: لولا أن أشق على أمتي لأمرتهم بالسواك مع كل وضوء.
Tabarani reported it in Al-Awsat (2/138, no. 1260), and this is his wording. Ahmad also reported it (968) in a longer context. Both came through Muhammad bin Ishaq, who said, my uncle Abdul-Rahman bin Yasar narrated to me, from Ubaydullah bin Abu Rafi, from his father, from Ali bin Abu Talib, and he mentioned it.Tabarani said, "This hadith is not narrated from Ali except through this chain, Muhammad bin Ishaq narrated it alone." I say, Muhammad bin Ishaq is truthful but a mudallis, however he has clearly stated that he heard it directly, so his chain is hasan. Haythami mentioned it in Majma al-Zawaid (1/221) and graded its chain hasan.Ahmad also narrated it (607) through Muhammad bin Ishaq, from Saeed bin Abu Saeed Maqburi, from Abu Hurairah, and also from Ubaydullah bin Abu Rafi, from his father, from Ali bin Abu Talib, similar to the hadith of Tabarani, except that Ibn Ishaq used "an" (an ambiguous form of narration) here, and he is a mudallis. His use of "an" does not affect the chain, since it has already been established through another route that he explicitly stated he heard it directly, as mentioned before.