A research achievement with teeth in it

EMERITUS. Thanks to the methodology for treating periodontal disease that he and his colleagues developed, people all over the world were able to keep their teeth. Jan Lindhe has devoted half a century to the study of periodontology and is still active as a researcher and international expert. 

“A day will come when we all bite gently into the bread.” Thus wrote Ivar-Lo Johansson in the 1952 book Ålderdoms-Sverige (The Sweden of Old Age), after a study tour of Swedish homes for the elderly. The photographs in the book show old men and old women with sunken cheeks and a short distance between nose and chin. That was the way so many people looked in the middle of the last century, especially in rural areas. Either they had lost their teeth or the dentist had pulled them out.

“If you take away all of a person’s teeth, it changes the whole face because the bones in which the teeth are embedded disappear. People didn’t think about that in the past when they extracted the teeth of both the old and the young,” says Jan Lindhe, who studied dentistry himself in the 1950s and has conducted research on periodontosis, peridontal diseases, since then.

Research, a part of everyday life

It’s a white wintry morning in Hovås, and in the hall of Mr. and Mrs. Lindhe’s home stand wet walking shoes with traction devices. Daily walks of between five and seven kilometers are part of their routines, as are reading and research.

“Maybe it has to do with a lack of imagination,” says Jan Lindhe, about the fact that he still writes scientific papers, even though it has been more than 15 years since he retired from his professorship at the Institute of Odontology at the University of Gothenburg.

Jan was 34 when he was recruited in 1969 from Umeå University to become a professor of periodontology in Gothenburg. Eight years later he became dean of the Faculty of Odontology, as it was called then. Except for five years as dean at the University of Pennsylvania in the United States, he remained in the Institute of Odontology at the University of Gothenburg until retirement. What he is most proud of when he looks back on his achievements is a groundbreaking system of methods to prevent and treat periodontal disease.

“When we started to research periodontoclasia, no one knew for sure why people lost their teeth, as it was called. We operated on the hypothesis that it was caused by bacterial coatings on tooth surfaces that initiated an inflammation of the gums and destroyed the anchorage of teeth in individuals who were particularly susceptible. Ultimately we were able, through clinical and animal experimental studies, to show that the theory was correct.”

Initially encountered resistance

Based on this new knowledge, Jan Lindhe and his graduate students began treating patients who have lost so much of the supporting tissues around their teeth that they normally would have had them removed and replaced by prostheses. By surgical removal of gum pockets in which the bacteria thrived and following this up with long-term preventive care, strategically important teeth were saved. They could then be used to anchor bridges that gave patients good ability to chew.

“This aroused some resistance at first. In Europe and the U.S., dentists were attaching bridges to diseased teeth and in mouths where the bacteria continued to wreak havoc. Consequently, the bridges didn’t last very long.”

When Jan and his colleagues were able to demonstrate that their patients remained healthy, the criticism died down. Another important conclusion of the research was that periodontal disease could be held in check at an early stage by means of preventive measures. The methodology was disseminated, including to Japan, by one of Jan Lindhe’s doctoral students.

Wanted to be a journalist

Over the years Jan has written more than 400 scientific articles, supervised 30 PhD students from various countries, served as editor-in-chief of the Journal of Clinical Periodontology and written a textbook that is used throughout the world. The list of international distinctions, prizes and honorary appointments is very long and includes a prestigious medal from the Japanese emperor. Jan is consulted by international research teams, is in demand as a lecturer and continues to travel. But at home on the couch in the bright living room, he seems a bit embarrassed to talk about awards and accolades. He attributes some of his successes to chance, as if it were a coincidence that he started to conduct research.

“Most of life is a stroke of luck, you know. I can’t think of any single event that led me to become a researcher. One thing led to another. I studied to be a dentist, became especially interested in certain things and wanted to know more.”

Helsingborg resident Jan Lindhe studied to be a dentist in Malmö and continued with specialist training in surgery and periodontics in Lund, where he also earned a doctorate. But initially he wanted to be a journalist. During upper secondary school and academic studies, he wrote film reviews for Helsingborgs Dagblad. He has forgotten the editor’s name, but remembers that he wore a green eyeshade on his forehead and used a red pen mercilessly on young Jan’s creations. The editorial surroundings had great appeal, but Jan’s dad convinced him that it could wait. First, an education for a concrete profession with future prospects! Although he never returned to Helsingborgs Dagblad, Jan often thinks of the editor with a red pen with gratitude.

“I’ve made colossal use of what he taught me about writing. Nothing I’ve learned during my studies can compare with the education he gave me. Academia would do well to adopt a more journalistic writing style. For researchers to be able to evaluate each other’s methods and conclusions, they must be exact, simple and clearly described. That is not often the case.”

He shares his interest in the written word with his wife, Annalena, who is a dyslexia teacher. Both spend a lot of time reading fiction and periodicals. Jan Lindhe does not regret giving up his journalistic dream, but thinks that his father’s advice and chance have led him to the right place in life. At least once a week he rides to Medicinareberget and the Department of Periodontology, where he still has a study. Sometimes younger colleagues call on him when one of his former patients comes in for a checkup so that he can see with his own eyes that the teeth he treated in the 70s are still in place.

“It’s really great to meet again with patients you have had a long relationship with. And it actually makes me quite proud!”

TEXT: MALIN AVENIUS/FREELANCE JOURNALIST
PHOTO: ANNA-LENA LUNDQVIST