Is it ok in the Islamic law to have a gold tooth. A Muslim dentist told me that a porcelain tooth will breaks easily.

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and  Messenger.

There is disagreement among Muslim scholars concerning making use of a tooth of gold.

According to the schools of Malik, al-Shafi'e and Ibn Hanbal, it is lawful to use a tooth of gold. They based their opinion on the Hadith (reported by At-Tirmithi) of 'Arfajah Ibn 'As'ad who used a nose of silver when it (his nose) was cut on the day of Kilab. But, when such a nose of silver became bad-smelling, the Prophet ordered 'Arafajah to use a nose of gold.

Al-Athram reported from Musa Ibn Talha, Abu Jamrata al-Dub'i, Abu Rafi' Ibn Thabit al-Banani, Ismael Ibn Zaid Ibn Thabit and Al-Mughirah Ibn 'Abdullah that they tied their teeth with gold.

According to the school of Imam Abu Hanifa it is not lawful to use a tooth of gold except in case of need. This opinion is based on the Hadith that prohibit to use gold by men in general. It is also added that the narration of 'Arfajah was for a dire-need as stated by the Hadith. Here, it is safer to avoid such a use of gold as long as an alternative is available in silver, platinum or porcelain.

Allah knows best.