Musannaf Ibn Abi Shayba 18:239

Abu Bakr narrated to us, he said: Muhammad ibn Bishr narrated to us, he said: Sa'id ibn Abi 'Aruba narrated to us, from Matar, from 'Amr ibn Shu'ayb, from his father, from his grandfather, that the Messenger of Allah (may Allah bless him and grant him peace) said regarding the teeth: "Five, five."