The High Court has upheld a decision to strike off "for public protection" a dentist who tried to carry out work on a woman's teeth in a McDonald's.
Anca Claudia Macavei tried to fit a bridge in the Cannon Street, London, branch of the fast-food restaurant in 2012.
Ms Macavei argued that a General Dental Council professional conduct committee decision in July 2014 to strike her off the register of dentists for that incident and other misconduct was a "disproportionate sanction".
But today, Mrs Justice Patterson, sitting in London, dismissed her appeal.
The judge said: "In my judgment, the committee had ample evidence to conclude that they were dealing with a registrant whose attitude to criticism and defects in her practice, together with her response to offers to help her over a period of some years, showed that she had little insight into her problems."
The judge added: "Against that background, the committee were entitled to conclude that they could not be confident that the public would be protected by an approach less than erasure."
Miss Macavei, a Romanian dentist who previously practised in Tavistock, Devon, was living in London and advertising for Romanian patients online when she met the woman known as Patient 1.
The court heard that she had an arrangement to use the Cannon Street Practice surgery on an "ad hoc basis", but her relationship with the practice manager had deteriorated and in February 2012, she met Patient 1 in McDonald's.
When the woman refused to be treated there, Miss Macavei tried to carry out the work in the hallway outside of the dental surgery.
Miss Macavei has been suspended since the decision last July awaiting the outcome of her appeal.
She said of the striking-off decision during the appeal: "It was too hard to me and I think it was disproportionate. It was a very tough decision."
Ms Macavei arrived in the UK from Romania in November 2010 and the first post she held was in Devon between April 6-21 2011, said the judge.
She was suspended because of numerous concerns, including record-keeping, X-rays and concerns expressed by dental nurses about her practice.
There were six complaints in seven days, and in May 2011 she gave an undertaking not to practise in the NHS and later moved to London.
When asked during the professional conduct committee hearing how she would feel about "picking up a high-speed drill and working on a patient tomorrow", she replied: "I will not have any fear."
The judge said the case before the committee concerned Ms Macavei's treatment of two patients, referred to as Patient 1, treated between February-May 2012, and Patient 2, who was treated December 2011-May 2012.
The committee found that in both cases her standard of care and treatment "fell below that reasonably expected of a dental practitioner".
The committee told her: "Further, in the case of Patient 1, you attempted to provide dental treatment in unsuitable environments, namely in a McDonald's restaurant and in the hallway outside a dental practice.
"She (Patient 1) stated that you tried to put bridges in her mouth whilst in the McDonald's and, when she refused, you insisted that it was necessary to see if they would fit."