Abu Bakr bin 'Abdur Rahman أبو بكر بن عبد الرحمن بن الحارث بن هشام · Fasting (Kitab Al-Siyam)

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."

A man asked the Prophet (ﷺ) whether one who was fasting could embrace (his wife) and he gave him permission; but when another man came to him, and asked him, he forbade him. The one to whom he gave permission was an old man and the one whom he forbade was a youth.