The Spanish recipient of the world's first face transplant has appeared before TV cameras to thank surgeons and his donor's family.

A shooting accident five years ago meant the patient, known only as Oscar, needed his entire face replaced.

The 31-year-old farmer was unable to breathe, swallow or talk properly after accidentally shooting himself in the face.

Overnight, Oscar revealed his new look.

He still struggles to be understood, but his sentiment was loud and clear. Oscar thanked his medical team, his family and the family of the face donor.

During the 24-hour surgery in March, doctors lifted the donor's entire face - the jaw, nose, cheekbones, teeth, eyelids, muscles, nerves and blood vessels, placing it mask-like onto Oscar's face.

He is still swollen and needs more than a year of therapy, but doctors say he should regain up to 90 per cent of his facial functions.

The assistant director of Vall d'Hebron Hospital, Pilar Solans, says the operation will give freedom back to his patient.

"I just want to thank Oscar for trusting us. It's still not finished; he has spent four months here, that's too many months isn't it?" he said.

"That's a lot of time to be ill in hospital. Now he needs to take walks and breathe some fresh air, he needs to be with his loved ones and be free.

"Now this moment has arrived and he is leaving today. That doesn't mean that he won't need to come back many times, but it's not the same thing."

Beard growth

Doctors say Oscar has now regained feeling in most of his face. One good sign a week after the operation was that he had to be shaved because of beard growth.

He suffered acute rejection twice, but his new face was saved by medication.

Oscar's sister, who also declined to be named to protect the family's identity, says her brother has retained many of his quirks.

She says he is looking forward to being normal again.

"He recognised himself from the very first moment, as we did, he has kept some of his previous expressions and he did not have any strange sensations," she said.

"He wants to have a life like he used to have, being able to walk down the street without people looking at him strangely, being able to sit down with his family for lunch, all together, and being able to carry on with a normal life, like each one of us does."

It is the world's first full face transplant - a partial one was carried out in France in 2005 on a woman who had been mauled by her dog.

Since then, about 10 similar ones have been performed around the world.