Last year brought a significant milestone in cutting-edge medicine when former firefighter Patrick Hardison received the most extensive face transplant surgery ever performed. Hardison’s operation rounded out nearly a decade since the first face transplant was done in 2005, a period during which a scientific feat that once seemed to belong to the realm of science fiction became possible and moved closer to the mainstream. Not only were technical limitations transcended, but initial moral objections were also overcome. Here is a look at the evolution of this groundbreaking procedure—and the people whose lives were changed by it.

1. THE GIRL WHO GOT HER OWN FACE BACK // 1994

In 1994, 9-year-old Sandeep Kaur was working in a field in India when one of her pigtails was caught in a threshing machine. The machine’s gears pulled in the girl’s hair and peeled her face off in two pieces. Her family brought her to the nearest hospital, which was three hours away. Determining that skin grafts would not work, the doctors made history by performing what was essentially the first face transplant surgery. Technically, though, since it was the victim’s own face that was being replaced, this early operation counts as a face "re-plant" rather than a transplant.

2. THE WOMAN WHO GOT HER MOUTH AND NOSE REPLACED // 2005

Isabelle Dinoire’s partial face transplant made headlines not only for the pioneering science it involved, but for the circumstances surrounding it: Dinoire, apparently in the midst of some emotional distress, had taken some sleeping pills and awoke to discover that her dog had chewed off her lips and nose while she was unconscious.

In November 2005, doctors Bernard Devauchelle and Jean-Michel Dubernard—who led the French team that had done the first-ever modern hand transplant in 1998—performed the world’s first partial face transplant, grafting a triangle of tissue from a brain-dead woman’s mouth and nose onto Dinoire. Dinoire was able to eat and speak within a day and reported satisfaction with the results 18 months later. However, she suffered a series of tissue rejection episodes during that time, pointing to the need for transplant recipients to take immunosuppressant drugs for their entire lives.

3. THE DOMESTIC VIOLENCE VICTIM WHO HAD 80 PERCENT OF HER FACE RECONSTRUCTED // 2008

In 2008, Connie Culp became the first person to receive a partial face transplant in the United States. Culp’s husband had shot her in the face during a domestic dispute, destroying her mouth, nose, cheeks, an eye, and a section of bone and teeth in the center of her face. Her operation was performed at the Cleveland Clinic, the first American clinic to approve the procedure. The extensive, 22-hour operation, involving 80 percent of Culp’s face, required removal of previous makeshift construction of her jaw structure and transplantation of bone, muscle, nerves, blood vessels, and skin to reconstruct the midsection of her face.

4. THE FARMER WHO UNDERWENT 10 ATTEMPTS TO REBUILD HIS FACE // 2010

In 2010, a Spanish farmer who had been horribly disfigured in a gun accident, identified only as Oscar, became the recipient of the world’s first full-face transplant at a Barcelona hospital. Nine early attempts to rebuild Oscar’s face had failed, making him a candidate for the experimental procedure. The 24-hour operation required a team of 30 surgeons, anesthetists, and nurses to replace Oscar’s facial muscles, nose, lips, upper jaw, teeth, cheekbones, palate, tear ducts, and eyelids. Oscar’s surgery was followed just a few months later by the world’s second full face transplant in France.

5. THE BURN VICTIM WHO WAS ABLE TO SPEAK AND SMELL AGAIN  // 2011

Dallas Wiens says he remembers nothing of the November 2008 accident when, while on a cherry picker, his head hit a high-voltage wire, sending electricity coursing through his body and severely burning him from head to toe. The incident blinded him and obliterated his facial features. Improbably, Wiens survived the accident and began to make a recovery, but it was a 2011 full face transplant operation that would return him to life. The operation, carried out at Brigham and Women’s Hospital in Boston, replaced the entirety of his face with that of a donor and returned his ability to speak and smell (though surgeons were not able to bring back his eyesight).

Wiens’s surgery was followed by full face transplants in the United States on Mitch Hunter later in 2011 and a very extensive operation on Richard Lee Norris in 2012.

6. THE CHIMP ATTACK SURVIVOR WHO RECEIVED A NEW FACE—AND HANDS // 2011

While not as much of a milestone in terms of face transplant science, Charla Nash’s story is notable for the extremely bizarre circumstances surrounding it. In 2009, Nash drove to the Connecticut home of her friend and employer Sandra Herold to help her corral her pet chimpanzee Travis, who had gotten out of control that day. Upon her arrival, Travis, a full-grown, 200-pound male, viciously attacked Nash, ripping off her face and hands.

After several earlier surgeries, Nash eventually received face and hand transplants in May 2011 at Brigham and Women’s Hospital. Both transplants were initially successful, but the hand transplants eventually had to be removed after Nash developed an infection. Nash continues to recover and it is hoped that her progress will inform future operations on veterans returning from war.

7. THE MAN WHO GOT A NEW FACE IN JUST THREE WEEKS // 2013

The first of two face transplants performed in Poland is remarkable mainly because of the extremely short time period within which it was carried out. A male patient, identified only as Grzegorz, received a full face transplant just three weeks after he was injured in a machine accident at work in 2013, losing his nose, upper jaw, and cheeks. The delicate nature of face transplant surgeries usually necessitates months or even years of preparation, making this particular operation the fastest ever performed. Doctors deemed the speed necessary because the accident had left an area of the brain exposed to infection.

8. THE FIREFIGHTER WHO RECEIVED THE BIKE MESSENGER'S FACE // 2015

In 2001, volunteer firefighter Patrick Hardison rushed into a burning home in Senatobia, Mississippi, to rescue a woman he thought was inside. The roof collapsed, knocking his helmet from his head, melting his mask, and searing his skin. The accident left Hardison without ears, nose, lips, or eyelid tissue and with virtually no normal skin left on his entire face and neck. Over 70 surgeries and grafts had left him a patchwork of scars and in constant pain, with limited vision due to lack of functioning eyelids.

In August 2015, surgeon Eduardo Rodriguez performed the most extensive ever face transplant on Hardison at NYU Langone Medical Center, using donated tissue from David Rodebaugh, a Brooklyn bike enthusiast who died following a bike accident. The transplant extends from the back of Hardison’s skull, over the top of his head, and down to his collarbones, and includes eyelids and both ears.

CHALLENGES AHEAD FOR THE PROCEDURE

The relative success of these operations has dispelled many, but not all, of critics’ fears. When face transplants were first proposed, some doubted the transplants would have feeling and functionality, but patients have regained their senses of smell, taste, and touch. Nonetheless, the delicate procedure, requiring years of training, microsurgery techniques, and large teams of specialists, is still in its early stages, and there is much room for improvement. Each face transplant surgery performed so far has followed a slightly different protocol, and the technology is in need of standardization. Surgeons are exploring new ways to match donor and recipient anatomy and improve alignment using CT scans and 3-D printed replicas of the anatomy involved in order to improve planning and speed up the process. The surgeries, too, carry a steep price tag—about $300,000 on average—and American health insurance plans do not cover it, a situation many hope will change.

Then there is the ongoing moral debate over the process. Initial objections revolved around sheer revulsion at the concept and identity-based misgivings. But while some recipients have expressed feelings of responsibility toward the donor’s legacy, few have reported identity crises about wearing a donated face. The current moral debate largely concerns the immunosuppressant drugs that patients must take in order to avoid rejection of the foreign tissue. Such drugs can negatively affect health, increasing risk of cancer, diabetes, and other ailments. Critics argue that the procedure, while life changing, is not life saving, and that it is essentially putting otherwise healthy people at risk of death. 

Finally, while the public may be warming up to face transplants, scientific advances will undoubtedly open new cans of morally questionable worms. Italian surgeon Sergio Canavero has declared that he will perform the first full head transplant in 2017. Most neuroscientists are highly skeptical that's possible, but the future undoubtedly holds stranger things yet.