Dentist Omer Butt, 31, is said to have told the patient that he would refuse to register her as an NHS patient if she did not cover her head, the General Dental Council (GDC) was told.
The woman, who is a non-practising Muslim and works as an NHS community nurse, was in so much pain she agreed to borrow a headscarf from a nurse at Butt's clinic in Bury, Lancashire, it is said.
A British Muslim dentist has told the female patient, that he would treat her only if she wore an Islamic headscarf.
One of the nurses is said to have warned the young woman - who is being referred to only as Patient A - that 'inside the surgery it is Dr Butt's world and his rules that apply'.
Following the woman's complaint, Butt wrote a letter to the GDC praising Allah and concluding: 'May Allah protect us all from the evils of Shaitan (Satan).'
But she stormed off when Butt told her to wait in the waiting room, saying she felt 'humiliated and upset' by what had happened.
Butt, who is registered as of Sheepfoot Lane, Prestwich, Manchester, admits quoting the Ahadith at Patient A but denies it was the practice policy to insist on a Muslim dress code. He also denies telling her he would not register her as an NHS patient and also denies misconduct.
He could be struck off if he is found guilty of serious professional misconduct.
The charges say that Butt undermined public confidence in his profession by discriminating against a patient and failed to act in her best interests.