Hospital spokesman Kevin Myron said the 17-hour operation took place Thursday at Harvard-affiliated Brigham and Women's Hospital. A team led by plastic surgeon Dr. Bohdan Pomahac replaced the man's nose, palate, upper lip, and some skin, muscles and nerves with those of a dead donor.
The hospital would not identify the donor or the recipient, but plans a news conference Friday afternoon.
It's only the second such procedure to have been performed in the U.S, reports CBS Station WBZ.
In a phone interview on Friday, Pomahac said the man's injury occurred some years ago, and it left him with "no teeth, no palate, no nose, no lip."
"It was difficult for him to speak, to eat, to drink. It certainly caused a lot of social problems," Pomahac said.
The man had been Pomahac's patient for a long time, and doctors decided to pursue a face transplant because previous attempts to treat him left him still badly deformed. It took three months to find a suitable donor, who also provided some organs for transplant in other patients, Pomahac said.
The operation began at 1:15 a.m. Thursday, with the recipient and the donor in operating rooms across the hall from each other. The recipient was still recovering from anesthesia on Friday.
"He's still not fully awake so he has not seen himself. We have not really had a meaningful conversation so far," Pomahac said.
"He was incredibly motivated to go forward with it," and was extensively evaluated psychologically by doctors in and outside of Brigham, Pomahac said. "We really made sure that nothing was left to chance."
The seven main surgeons and other assistants all donated their time and services, Pomahac said.
"This is a patient that we have known for a long time. We have prepared him for a long time. We are essentially taking a lifelong commitment to help him."
Pomahac was born in Ostrava in the Czech Republic, and graduated from Palacky University School of Medicine in Olomouc, Czech Republic. He came to Brigham for a surgical research internship in 1996 and now, at 38, is associate director of its burn center, where he treats trauma and plastic surgery cases.
The Boston hospital's board approved Pomahac's plans to offer face transplants a year ago.
The first U.S. face transplant was done in December by doctors at Cleveland Clinic who replaced 80 percent of a woman's face with that of a female cadaver. The woman's identity has not been revealed, nor the circumstances that led to the transplant, except that her injury occurred several years ago.
The woman left the Cleveland hospital in February, and her progress was described as astonishing by her doctors.
A Connecticut woman mauled by a chimpanzee is also recuperating at the Cleveland clinic and might be a face transplant patient sometime in the future after she recovers from serious injuries.
The Boston surgery is the world's seventh face transplant, as an operation once considered the stuff of science fiction is suddenly becoming more common.
Last weekend in Paris, doctors performed the world's first simultaneous face-and-hand transplant on a man who suffered severe burns. In that case, doctors replaced the upper half of the man's face and both his hands, all the parts coming from a brain-dead donor.
French doctors also did the world's first transplant, in 2005, on a French woman who had been mauled by her dog.