For the first 21 years of his life, Dave Johnson had been known to pediatricians as an FLK: a funny-looking kid. But even that label understated the problems of the young man who walked into the office of a local oral surgeon last winter and said: "I just feel like I'd rather face the world with a different face."

The face of Dave Johnson -- not his real name -- was a narrow, inverted triangle, tapering down, down, down to a sharply pointed chin twice as long as that of a normal person. His eyes were large and blue, but appeared much too prominent because the cheekbone below them receded backward instead of jutting forward as others do.

He reminded one observer of the men seen in the works of the Spanish painter El Greco. But from childhood on, he had reminded his peers of someone else. "Ever since he was so high," said his mother, "he has been called Frankenstein."

For many years, the mother had been thinking about facial surgery for Dave, whose birth defect, cerebral gigantism, had made his face grow so disproportionately in some directions and very little in others. But not until her mildly retarded son finished high school and ventured out to find work did the full impact of that unusual face compel mother and son to seek a permanent remedy.

The face was losing Dave jobs.

And so, several months ago, Dave andhis mother approached Dr. Peter W. Connole, an oral surgeon at the Washington Hospital Center. As their discussions on reshaping Dave's face progressed, the feelings of mother and son took an interesting turn. Mrs. Johnson became frightened that surgery would in effect take her son away, that she would no longer recognize him. Dave became more and more determined to change his face. Said Dave to his mother: "You don't have to live behind it."

Dave Johnson lay asleep on the operating table last Thursday, with a respirator pumping oxygen and anesthetic through a tube in his nose, as Dr. Connole and his team began exposing the bone of his upper jaw. Two or three surgeons were there to assist, and several others stood ready to relieve them in shifts during an operation that could take 14 hours. For Connole, there would be no relief.

Connole delicately stripped the tissue of Johnson's cheeks off the bone until his skull showed cleanly up to the lower borders of his eye sockets. Before he was through, Connole would slice through the bones of Johnson's upper jaw and chin, drill away the excess, move his entire mid-face forward, graft pieces of hipbone to build up the receding cheekbone, and then wire it all back together again.

In the past 10 years, oral surgeons have tackled more and more drastic types of facial reconstruction. Starting with surgery on the lower jaw, they have expanded their field to include the upper jaw and cheekbone and sometimes the palate. Advances in oral surgery have depended not on new technology, according to Connole, but on learning what surgeons could get away with safely.

Trying desperately to repair serious fractures of facial bones, surgeons found they could cut and wire whole sections of the skull without risking serious infections or destroying blood vessels that supply the face. Virtually everything they do can be done through the mouth, without cutting through facial skin and thus without producing scars.

Similar bone-rebuilding operations are performed by plastic surgeons and neurosurgeons on the upper half of the skull so that most serious facial deformities are now surgically correctable. Connole said that Johson's operation was complex only in its scope -- the individual steps in it are performed thousands of times a year in hospitals all over the country, including several in the Washington area.

Beyond the mechanics of surgery, what fascinates Connole is how a transformed face affects his patients. For years, he has observed their reactions, and those of their spouses and families.

For most people, there is a permanent personality change. And the greater the change in the face, the greater the change in the person. "Its not just a euphoria," said Connole. "There is a very positive self-assurance that seems to develop."

Most of his patients have grown up as loners, usually with a tight-knit family that accepts them but with few close friends. Their response to surgery depends on how realistic their expectations are. Unquestionably, the operation changes their lives, but Connole said those who believe a new face will solve everything are cruelly disappointed.

He said others suffer temporary depression for a different reason. "They are bitter because people are accepting them more," he said. "They feel people's acceptance of others is very superficial." After a time, those feelings usually subside.

For a patient's family, the adjustment can be more difficult. The spouse of someone with a severe deformity, according to Connole, often opposes the operation.

"They feel they won't have the same hold on the individual," he said. "Probably they feel unsure of their relationship. [It happens] for the same reasons a fat person's wife may not want him to lose weight."

Connole took what looked like an over-sized dentist's drill and cut a straight line across the bone of Johnson's upper jaw just below his nose. Then he made a much more complicated cut across the upper cheekbones, skirting the lower rims of the eye sockets and avoiding the large nerves that travel through holes in the bone beneath each eye. Cuts at the sides of the cheekbones connected the two horizontal ones, effectively separating a whole section of Johnson's skull. The surgeons used hammers and chisels to finish fracturing the bone.

"You almost have to take Shop 103 inhigh school to be able to do this," said Connole.

Ten years ago, an orthodontist had told Mrs. Johnson to forget about facial surgery for Dave, that "it wouldn't be worthwhile." The remark had rankled her ever since. Yet, once the opportunity was held out, the family was undecided for months.

The Johnsons had lost a daughter to cancer, and had too much experience with hospitals and doctors. This was the first time any of their five children had faced surgery that wasn't strictly necessary.

"I was against it," said Dave's father, an oceanographer. "I told him I didn't think he was bad enough to go in and have surgery. He thought he was." d

Mrs. Johnson, who had always been in favor, nearly changed her mind at the last minute. She even asked Connole to put the operation off. Apart from fearing Dave would die, she said her worse fantasy was that it would leave him looking worse than before.

"I was looking at faces on the street," she said. "I had never seen so many ugly people. People don't look at ugly. Ugly is accepted. I was trying to figure out what the difference was between ugly and deformed."

She said Dave was particularly unfortunate because of his body and his manner tended to reinforce the Frankenstein image evoked by his face.

"He had the walk, and the look, and the general mental slowness that is characterized by this figure. I go back to the irony of it . . . In the book, Frankenstein was really a warm and loving person. That's what Dave is."

Connole drilled away a layer of bone from Dave's upper jaw to shorten the distance between his nose and mouth. He checked the result with a plastic model he had made, then wired the bone containing Dave's upper teeth back into place. Then he used an instrument to pull the entire cut-away section of Dave's mid-face forward, and wired that securely back onto the upper part of the skull.

Next he wired specially contoured pieces of bone onto the receding ridges of Dave's cheekbones. He reinforced all the cuts he had made with other bone grafts, taken early that morning from Dave's hip by a orthopedic surgeon. bThe live bone transplants would fuse with Dave's facial bones, strengthening them and promoting healing.

Finally, Connole gently stripped back the tissue of the lower lip and face from Dave's chin bone. He cut a carefully measured, horizontal wedge of bone out of the middle of the chin, and collapsed the tip of the chin upward to shorten it. He wired the chin back in place, replaced the tissue, and the operation was over. There was no facial stitches, and -- except for a small plaster on the chin -- no bandages.

The operation lasted 10 and a half hours, and it was more than three hours after that when Dave was wheeled from the recovery area back to his room. Connole had come out of surgery exultant, and told the Johnsons, "He looks very different." Mrs. Johnson said that frightened her more than anything.

"Walking down the corridor [to Dave's room] was very big for me," she said. "I have a habit of dying inside and holding back while my body is going faster and faster forward."

When she saw him, she said, "My first thought was, 'Oh my God, he looks himself.' I was so thrilled that he looks like Dave."

Nevertheless, she spent the night lying awake and worrying about how he would look when all the swelling disappeared. "I was thinking about Connole. wHe's happy as a clam. What did he say? 'He looks balanced.' Fine and dandy -- he's a surgeon. His idea of good may not match my idea of good."

On Friday, the day after the operation, Dave was sitting up in bed stroking his bandaged chin over and over to learn its new shape. His cheeks were slightly swollen and there was a little bruising below his eyes. Otherwise, his face looked utterly normal.

"I didn't want to have a long chin anymore," he said when asked why he had the operation. At the moment, he said, his chin felt numb and his cheeks smarted. His mother told him he looked scared, and he nodded.

"Why are you scared?" she asked.

"I don't know," said Dave.

His dream is to move to Laconia, N.H., where his family has always spent summers. His mother said it is the one place where he has always had friends and felt accepted. He spent last summer living there alone and working as a busboy, but his parents said he has always wanted a job as a hospital orderly.

"Maybe if his face is better," said Mrs. Johnson, "this time they won't say no to him."