Source: Tafsir al-Ahlam al-Kabir (Ibn Sirin)
Teeth in a dream represent the dreamer's household and relatives. The upper teeth are the men from his father's side, and the lower are the women from his mother's side. Their falling indicates the death, absence, or illness of the person they represent. If they fall into his hand or lap, it is wealth he will receive or a child. If they fall and he doesn't see them, one of his family members will die or be absent. Tooth decay indicates a calamity afflicting his household. The beauty and whiteness of teeth indicate the strength and prestige of his household.
Source: Ta'tir al-Anam fi Ta'bir al-Manam (Al-Nabulsi)
Falling teeth indicate a long life for the dreamer himself. If all his teeth fall out and he doesn't see them, his family and relatives will die before him. If his teeth fall out and he has a debt, Allah will settle his debt. If they fall and he catches them in his hand, he will benefit from wealth from the person the tooth represents. Teeth falling out with blood indicates sin and severing family ties. Black or crooked teeth indicate a flaw in the household members.
Source: Al-Isharat fi Ilm al-Ibarat (Ibn Shahin)
The vision of falling teeth is interpreted in several ways: the death of a relative, payment of a debt, wealth that comes to him, or bad words he utters. Whoever sees his teeth fall into his palm without pain, it is wealth that will come to him. If they fall with pain and blood, it indicates the loss of something from his house with hardship and worry. Pulling out teeth indicates severing family ties or spending money reluctantly. Cleaning teeth indicates spending money to remove the worries of one's family.