Dr. Per-Ingvar Branemark, a Swedish orthopedic surgeon and research professor whose accidental discovery made him the father of the modern dental implant, died on Dec. 20 in Gothenburg, Sweden, his hometown. He was 85.
The cause was a heart attack, his wife, Barbro Branemark, said.
Implants have been a major advance in dentistry, liberating millions of elderly people from painful, ill-fitting dentures, a diet of soft foods and the ignominy of a sneeze that sends false teeth flying out of the mouth. But addressing those problems was not Dr. Branemark’s initial intent.
At the start of his career, he was studying how blood flow affects bone healing.
In 1952, he and his team put optical devices encased in titanium into the lower legs of rabbits in order to study the healing process. When the research period ended and they went to remove the devices, they discovered to their surprise that the titanium had fused into the bone and could not be removed.
Dr. Branemark called the process “osseointegration,” and his research took a whole new direction as he realized that if the body could tolerate the long-term presence of titanium, the metal could be used to create an anchor for artificial teeth.
But first there was a long period of safety testing. Rabbits were not his only test subjects. To make sure that titanium would not be rejected by the body, Dr. Branemark enlisted about 20 students working in his lab to have titanium instruments inserted into their upper arms.
“You have to understand, every male in the lab was considered a volunteer, including my older brother,” said Dr. Tomas Albrektsson, one of Dr. Branemark’s longtime associates at the University of Gothenburg. “They all have a nice scar in their upper arm to this very day. I’m the only one who got out of it, saying that they needed me as the control group for the Albrektsson genes.”
Even after years of experimentation, though, it was difficult to convince the medical and dental establishment that titanium could be integrated into living issue. The conventional wisdom was that the introduction of any foreign material into the body would inevitably lead to inflammation and, ultimately, rejection.
Moreover, previous efforts to install dental implants, relying on mechanical devices to keep them in place, had failed miserably and left many patients in great pain.
For years, Dr. Branemark’s applications for grants to study implants anchored in bone tissue were rejected. The United States National Institutes of Health finally financed the project, and in the 1970s, Sweden’s National Board of Health and Welfare approved the Branemark implants.
An Advancement
The discovery that bone fuses to titanium — a process called osseointegration — led to permanent dental replacements.
REPLACEMENT CROWN
ABUTMENT
GUM
BONE
TITANIUM
IMPLANT
The implant locks into the jaw bone as cells attach to its titanium surface.
Dr. Branemark’s first titanium dental implant patient, in the mid-1960s, was Gosta Larsson, a man with a cleft palate, jaw deformities and no teeth in his lower jaw. The operation giving him four titanium implants allowed Mr. Larsson to use dentures until his death four decades later.
Still, Dr. Branemark’s innovation was poorly received. After Dr. Branemark gave a lecture on his work in 1969, Dr. Albrektsson recalled, one of the senior academics of Swedish dentistry rose and referred to an article in Reader’s Digest describing Dr. Branemark’s research, adding, “This may prove to be a popular article, but I simply do not trust people who publish themselves in Reader’s Digest.”
As it happened, that senior academic was well known to the Swedish public for recommending a particular brand of toothpick. So Dr. Branemark immediately rose and struck back, saying, “And I don’t trust people who advertise themselves on the back of boxes of toothpicks.”
A turning point came in 1982 at a professional meeting in Toronto, where Dr. Branemark made the case for osseointegration and won widespread recognition for his materials and methods. Since then, millions of people worldwide have been spared dentures because of his work.
Dr. Branemark’s system of dental implants is now manufactured and sold by Nobel Biocare, a publicly traded company. However, it is still sold as the Branemark System.
Titanium implants have spread well beyond dentistry: Osseointegration is now used in medical and veterinary applications.
For example, Dr. Branemark worked on titanium implants for people with large facial injuries and those who needed external hearing aids. One early patient, Dr. Albrektsson said, was a 15-year-old girl whose mother had taken thalidomide, and who had hearing problems as a result. The girl could not speak properly until Dr. Branemark put a titanium implant behind her ear and then attached to it a novel hearing aid.
Dr. Branemark was awarded the Swedish Engineering Academy’s medal for technical innovation, the Swedish Society of Medicine’s Soderberg Prize and the European Inventor Award for Lifetime Achievement, along with many other honors and honorary degrees.
In addition to his wife, Dr. Branemark is survived by three children from his first marriage, Annika, Rickard and Christian; and four grandchildren. Rickard works in his father’s field, developing prosthetic arms and legs anchored to the skeleton.
Mrs. Branemark, a nurse who worked closely with her husband for 40 years, said he disliked the word “implant.”
“Before they found out how to do it properly, before it was a science, implants destroyed a lot of patients,” she said. “He wanted to find another word — ‘fixtures’ is what he called them — for the titanium that integrates into the bone.”
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