Abu Mulaykah (may Allah have mercy on him) said: A man bit another's finger; he pulled his hand away, and the biter's tooth broke. The two of them came to Sayyiduna Abu Bakr (may Allah be pleased with him), and he declared it unavenged.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأشربة والحد فيها / 17642