All perfect praise be to Allaah, the Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and messenger.
Putting wax on the teeth does not invalidate fasting unless the wax reaches the throat without the person being overcome or forgetful when this occurs. If the wax reaches the fasting person's throat unintentionally or forgetfully, then he is not required to do anything either. Abu Hurayrah narrated that the Prophet, sallallaahu ‘alayhi wa sallam, said: “Whoever forgetfully eats or drinks while fasting should continue fasting. It is Allaah Who has given him food and drink.” [Al-Bukhari and Muslim]
Allaah Knows best.