I have seen the Messenger of Allah ﷺ using a tooth-stick while he was fasting. Musaddad added in his version: "more often than I could count." (Using translation from Abū Dāʾūd 2364)
رَأَيْتُ رَسُولَ اللهِ ﷺ يَسْتَاكُ مَا لَا أَعُدُّ وَلَا أُحْصِي وَهُوَ صَائِمٌ
I have seen the Messenger of Allah ﷺ using a tooth-stick while he was fasting. Musaddad added in his version: "more often than I could count."
رَأَيْتُ رَسُولَ اللَّهِ ﷺ يَسْتَاكُ وَهُوَ صَائِمٌ زَادَ مُسَدَّدٌ مَا لاَ أَعُدُّ وَلاَ أُحْصِي
[Machine] I saw the Messenger of Allah ﷺ doing things that I cannot count or enumerate while he was fasting. And 'Abdul-Rahman said, "I saw him using the siwak (tooth stick) while he was fasting."
رَأَيْتُ رَسُولَ اللهِ ﷺ مَا لَا أَعُدُّ وَمَا لَا أُحْصِي يَسْتَاكُ وَهُوَ صَائِمٌ وَقَالَ عَبْدُ الرَّحْمَنِ مَا لَا أُحْصِي يَتَسَوَّكُ وَهُوَ صَائِمٌ
[Machine] I cannot estimate or count how many times I have seen the Prophet of Allah ﷺ performing miswak while fasting.
مَا أُحْصِي وَلَا أَعُدُّ مَا رَأَيْتُ رَسُولَ اللهِ ﷺ يَتَسَوَّكُ وَهُوَ صَائِمٌ