A man bit another man's hand and the latter pulled his hand out of his mouth by force, causing two of his incisors (teeth) to fall out. They submitted their case to the Prophet, who said, "One of you bit his brother as a male camel bites. (Go away), there is no Diya (Blood-money) for you."  

أَنَّ رَجُلاً عَضَّ يَدَ رَجُلٍ فَنَزَعَ يَدَهُ مِنْ فَمِهِ فَوَقَعَتْ ثَنِيَّتَاهُ فَاخْتَصَمُوا إِلَى النَّبِيِّ ﷺ فَقَالَ يَعَضُّ أَحَدُكُمْ أَخَاهُ كَمَا يَعَضُّ الْفَحْلُ لاَ دِيَةَ لَكَ  

I fought in Jaish-al-Usra (Ghazwa of Tabuk) along with the Prophet ﷺ and in my opinion that was the best of my deeds. Then I had an employee, who quarrel led with someone and one of the them bit and cut the other's finger and caused his own tooth to fall out. He then went to the Prophet (with a complaint) but the Prophet ﷺ canceled the suit and said to the complainant, "Did you expect him to let his finger in your mouth so that you might snap and cut it (as does a stallion camel)?" Narrated Ibn Juraij from ʿAbdullah bin Abu Mulaika from his grandfather a similar story: A man bit the hand of another man and caused his own tooth to fall out, but Abu Bakr judged that he had no right for compensation (for the broken tooth).  

غَزَوْتُ مَعَ النَّبِيِّ ﷺ جَيْشَ الْعُسْرَةِ فَكَانَ مِنْ أَوْثَقِ أَعْمَالِي فِي نَفْسِي فَكَانَ لِي أَجِيرٌ فَقَاتَلَ إِنْسَانًا فَعَضَّ أَحَدُهُمَا إِصْبَعَ صَاحِبِهِ فَانْتَزَعَ إِصْبَعَهُ فَأَنْدَرَ ثَنِيَّتَهُ فَسَقَطَتْ فَانْطَلَقَ إِلَى النَّبِيِّ ﷺ فَأَهْدَرَ ثَنِيَّتَهُ وَقَالَ أَفَيَدَعُ إِصْبَعَهُ فِي فِيكَ تَقْضَمُهَا قَالَ أَحْسِبُهُ قَالَ كَمَا يَقْضَمُ الْفَحْلُ قَالَ ابْنُ جُرَيْجٍ وَحَدَّثَنِي عَبْدُ اللَّهِ بْنُ أَبِي مُلَيْكَةَ عَنْ جَدِّهِ بِمِثْلِ هَذِهِ الصِّفَةِ أَنَّ رَجُلاً عَضَّ يَدَ رَجُلٍ فَأَنْدَرَ ثَنِيَّتَهُ فَأَهْدَرَهَا أَبُو بَكْرٍ ؓ