By Clare Murphy
Health reporter, BBC News
A French woman who three years ago became the first person in the world to undergo a partial face transplant is by accounts adapting well to her new appearance - both physically and psychologically.
Isabelle Dinoire was the first person to have a partial face transplant
In the UK we could hear any day that a patient has been chosen to become the world's first recipient of a full face transplant.
This has received full approval from all the necessary ethics committees - although it remains unclear when it might take place - or indeed if a patient has even been found.
But whether this operation is days or years away, there is still fierce debate as to whether we really are ready for the cultural and medical implications of transferring a key part of someone's identity from a dead body to a living person.
Who am I?
In fact, for all the concerns about switching identity or "trading faces", those who treated Isabelle Dinoire note that she looks neither like the woman she was prior to being savaged by a dog, nor the dead woman whose face she inherited.
"The patient was very strong before the transplant and very sure of herself when she saw looked in the mirror immediately afterwards," Professor Bernard Devauchelle, who led the operation, told a conference in London aimed at addressing the continuing public discomfort around the issue.
"The transplant was very rapidly integrated into her life - it became a part of who she was."
French doctors have subsequently carried out two more such operations, and have the ethical authorisation to perform five more.
But even now, three operations on and with tangible benefits to those who had lived with horrific disfiguration, the criticism in France from some quarters has yet to abate.
The doctors stand accused of a number of ethical crimes - but one in particular stands out: transplantation is no longer a life-saving necessity, but has been transformed into a question of aesthetics.
This is a charge with which Dr Raj Persaud, a consultant psychiatrist at the Bethlem Royal and Maudsley hospitals, appears to sympathise.
"What is the cause of the suffering: is it society, or is it the face? Is not the real kernel of the problem society at large and its inability to see past that face?" he says.
"In essence doctors are doing a very peculiar thing. They are taking fit bodies and making them ill."
The long-term medical implications of face transplantation are as yet unknown - but there is little doubt that while the immense psychological burden of disfigurement may be at least partially alleviated, there are other significant risks to someone who is in every other respect healthy.
It is possible to grow human features, as scientists proved with this mouse
Ms Dinoire has had two "incidents", when her body's immune system tried to reject the foreign tissue, but so far immunosuppressive drugs are working.
But these drugs - which all transplant patients need to prevent their bodies rejecting the new organ - carry their own side-effects.
Diabetes and osteoporosis are among the consequences of medication which can also lead to renal failure, cardiac arrest, and increasingly, it is believed, cancer.
"What we are seeing as these patients live longer is that they are perhaps three times more likely to develop cancer than the general, age-matched population," said Professor Peter Morris, transplant specialist at the Royal College of Surgeons.
Skin cancer is among the most common. While it is generally seen as one of the most treatable forms of the disease, in the transplant population it "can be quite virulent and spread to other parts of the body much more rapidly", he said.
These risks may be acceptable ones to someone who, without a transplant, will die - and may be equally acceptable to someone whose disfiguration is causing them immense distress.
"But patients need to be aware of these risks, and at present the risk/benefit ratio is impossible to determine," he said. "What's clear at any rate is that these procedures cannot be done without immense psychological and psychiatric input."
There is hope that a number of these thorny ethical and medical issues can be overcome by "growing" a new face, rather than depending on a dead donor.
Using the patients own bone and tissue in reconstruction is one line of inquiry, but the work is still at an early stage.
Stem cells are also a key avenue. But while scientists can grow the complex components of the face individually, combining them into a custom-made, multi-layered face is another question.
"You wouldn't have the problems of rejection, you'd have better control over appearance, and ethically it would be much easier," says Francis Hughes, professor of periodontology at Barts and the London School of Medicine and Dentistry.
"But it is a lengthy process involving many stages - and at present it is still just an aspiration."