Waqid bin Abdullah al-Tamimi narrates from someone who saw Sayyiduna Uthman (may Allah be pleased with him) that he had had gold fixed to his teeth.
Abdullah bin Ahmad recorded it; its chain contains a narrator who is not named. The rest of its narrators are thiqat (trustworthy).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب اللباس / 8714