The oldest case of gum disease has been unearthed. The “patient” was a human that was alive over 1,000 years ago, living in the middle of the Middle Ages. Though we’ve come a long way in terms of technology in dental care, the Medieval man suffered from gum disease caused by the very same bacteria that modern man is afflicted by. The 1,000 year old man had a lot to teach scientists.
What makes this discovery so exciting is that much of the man’s teeth, food debris and bacteria have been preserved. The plaque preserved these features and then hardened to form tartar (or calculus), miraculously standing the test of time. This is due to calculus’s greater resilience and stability when compared to bone, which quickly loses much of its molecular information when buried. Indeed, it is the plaque—not the skull, teeth or anything else—that provides a glimpse into the way of life back then. The calculus preserved food debris, revealing certain aspects of the Medieval man’s diet that aren’t found in fossil evidence, namely vegetable consumption.
That’s what one of the scientists called the preserved microbes found in the tartar. This provided some stunning information never seen before in human remains. First, the bacteria that they found in the tartar already contained the genetic components for antibiotic resistance. So nearly 1,000 years before antibiotics were introduced, bacteria already had the potential to undermine our medicines. It was an arduous task, however, of piecing together millions of genetic sequences in order to reconstruct the oral microbiome. Using a technique called shotgun DNA sequencing, the team of scientists was able to fully reconstruct the ancient gum pathogen. For possibly the first time, scientists produced genetic evidence of dietary biomolecules from millennium old tartar.
The discovery teaches us not only about human biology and life, but also that of the periodontal bacteria. Studying teeth and calculus can shine a light on how human mouth bacteria has evolved and origins of gum disease in general. Periodontal disease has an interesting track record. It’s commonly found in humans, domesticated animals and zoo animals. When it comes to wild animals, periodontal is quite uncommon, suggesting that the disease arose in response to changes in human lifestyle. That could be a change in diet, adoption of a sedentary lifestyle or introduction to a new environment. All of this insight into the nature of past human biology thanks to dental plaque—the only time we look upon it in a positive light.