From a distance, at a glance, Doc’s case could seem a success. In most any other war, most any other context, the bullet that blew out the right side of his face would have taken with it his life. Instead, Doc took his place in the long, scarred line of living exhibits showing how the American military was rushing gravely wounded troops from the battlefield and treating them with skills and confidence no American fighting force had known before. In 2007, he was back in the States, still in uniform, helping to train new corpsmen for the combat lifesaving skills they would need in Afghanistan and Iraq. All the while doctors kept working on his face.

Those who knew Doc well understood that his recovery did not proceed as far as he hoped, and that the neat stories of maimed but rebounding veterans, a feel-good genre of the period, did not quite apply to him. Doc had dodged death to face a cascade of problems: chronic pain, migraines, PTSD, insomnia. His rebuilt jaw did not line up with his teeth. He retained enough of his tongue that he was able to compensate for speech, but the altered shape of his oral cavity and the damage to his tongue made eating difficult. Sometimes he had to chew food on one side of his mouth, then manipulate it toward his throat with his left index finger. By 2008 his brief marriage had ended. Within a few years he racked up 32 operations. He was jumpy, brooding and self-conscious. To manage pain and sleeplessness, and the loneliness, he took to drinking, sometimes to a restless stupor.

When he was medically discharged from the Navy in 2012, he was stripped of a sense of purpose and belonging. When I visited him that spring, he began drinking before we ate lunch. New physical problems presented themselves, in forms only a person who has suffered a devastating wound to the mouth can know – bits of teeth loosened and dropped out, later followed by a chunk of bone and a screw. Doc gained weight, added tattoos and grew a beard, which partly hid the fact that his jaw, his teeth and his mouth were getting worse.

By last year he had dialed back his drinking, was in a new relationship and had become a father. But still he struggled to move forward, and his confidence in the Department of Veterans Affairs plummeted. As his dental pain became unbearable, he called for appointments. The V.A. offered him tooth extractions, he and his mother said, after a wait of several months. Tooth extractions were never going to be enough.

Doc sensed that his government-funded facial reconstruction had crested, and now was failing. He had no plan. Last year he was 31, tormented by pain and backsliding. “We were at a point where there was not much more they could do,” he said.

One night he pulled out an offending tooth with the pliers on his Leatherman tool. Two nights later he removed another. When his mother, Gail Kirby, understood what he had done, she pleaded with him, asking what he wanted, what someone might do to help. “He said, ‘Mama, I want my face,’ ” she said.

He had been lean and handsome before.

His mother had an idea. It was a long shot.

In 2007, Doc attended a benefit dinner honoring veterans at the Waldorf Astoria. It was hosted by the Marine Corps-Law Enforcement Foundation, a private organization that provides college scholarships to the children of Marines and federal law-enforcement officers killed in the line of duty. He was the guest of Jack Doyle, an investment portfolio manager and foundation donor whose brother-in-law, Dennis M. Edwards, was killed in the terrorist attacks in 2001 on the World Trade Center. There Doc met a pair of brothers — a doctor and a dentist — who said that if he ever needed care, they would help. The dentist was a former Marine. Doc had mentioned the meeting to his mother, but in the ensuing years he thought little of their pledge. He forgot their names. “I just thought, That was nice of them to say,” he said.