Lyon, France ? As she held the mirror up to her new face, the woman looked at her reflection. She paused for a moment. Unable to speak because of the breathing tube in her throat, she wrote a note, “Merci.” Thank you.

Then, she cried. Dr. Sylvie Testelin, one of her surgeons, cried too.

The results of the daring nose, lips and chin transplant – the first ever attempted – were beyond what the doctors had hoped for. The new face bore an uncanny resemblance to her former face, one doctor said.

The 38-year-old divorced mother, who doesn’t want her identity known, had been mauled in June by her dog, a Labrador retriever mix adopted from a rescue shelter. The lower half of her face had been ripped off.

Before last Sunday’s operation, the woman couldn’t chew her food. She had trouble speaking. Whenever she tried to drink something, most of the liquid dribbled from her mouth. She would only go out in public wearing a surgical mask to protect her from stares.

Conventional reconstructive surgery may have been possible, but it would have been very difficult, if not impossible, to restore not only her appearance, but also basic functions, her doctors said Friday at the first news conference since the surgery in northern France.

Several expert advisers agreed that traditional surgery involving skin and muscle grafts from elsewhere on the woman’s own body was not a viable solution, the doctors said.

This image released by the Lyon Hospital shows a model of the defects in the first partial face transplant. A 38-year-old woman, whose identity has not been disclosed, had surgery on Sunday to replace her nose, lips and chin in Amiens, northern France.

Leading transplant surgeon Dr. Jean-Michel Dubernard acknowledged that he initially had reservations. But he added that when he saw the extent of the woman’s disfigurement, “I no longer hesitated for a second.”

“If we didn’t perform this operation, her outcome would have been quite poor. She would have had to undergo four, maybe five conventional surgeries over a long period of time, with uncertain results,” said another of her surgeons Dr. Benoit Lengele, of the Saint-Luc University Clinic in Brussels, Belgium. “We wanted to try to restore her as best as possible and as quickly as possible. We truly believe from the human standpoint and the scientific point of view that the solution we took was the best one.”

Dubernard said the cost of the operation hasn’t been calculated. It will be paid for by the French government’s tax-funded health system, as is most French health care.

Surgical team leader Dr. Bernard Devauchelle said the team was “totally stupefied” by how perfectly the transplant was integrated into her face in terms of the color and the thickness of the skin.

The woman already has some mobility in the new tissue. She can eat, drink and speak clearly, Devauchelle said. But it will be another six months before the nerves start to regenerate. It’s too early to tell how natural the transplant will look, but the doctors said they were optimistic.

The biggest hurdle now is the body’s acceptance of the transplant. The woman must take drugs for the rest of her life to prevent her immune system from rejecting the tissue.

It’s still possible that the surgery will fail, that the new tissue on her face might die and turn black, even months later. In that case, reconstructive surgery or a new transplant would be needed.