It is the stuff of nightmares. Every day, we wake up and go through the same routine to try and steer clear of a collective anxiety — losing our teeth.
We brush twice a day, attempt to floss, and go to the dentist every six months (OK, every ten...). Dental anxiety affects 36 percent of people in the United States, according to one study. But for scientists, dental workups can reveal much more than a bad case of gingivitis.
Rather, teeth act like the rings of trees, preserving information about our identities and revealing key details about human lives long after death — they can also provide crucial clues to how other human species lived, too. In a new study, researchers conducted a full dental workup of a 150,000-year-old Neanderthal skull in a cave in Italy, unearthing some surprising findings of our prehistoric kin hidden in an all-too-familiar problem — toothy decay.
The Neanderthal in the dentist's chair was initially discovered near Altamura, Italy, in 1993. But this study is the first to thoroughly examine its teeth and maxillary jawbones — and the first in the world to find a surprising connection between us and our ancient human peer.
The findings were published Wednesday in the journal PLOS ONE.
Excavation Time — Before the researchers could get close enough to the Neanderthal's teeth to do a full examination of its dental history, the scientists first needed to reach the ancient hominin's skeleton.
"The specimen is located in a small chamber of the Lamalunga cave. Getting to the corner where the skeleton is located requires quite a bit of crawling and going through narrow fissures," Jacopo Moggi-Cecchi, a co-author on the study and a professor at the University of Florence, tells Inverse.
To make matters more difficult, the ancient skeleton is covered in white calcite deposits, obscuring much of it from view. But it is a remarkably well-preserved skeleton nonetheless.
"Although the skeleton of the Neanderthal from Altamura is deep inside the Lamalunga cave, partly incorporated into calcite concretions and covered by coralloid formations, most of the bones are visible, including the cranium, the mandible, several post-cranial elements and both the dental arches," Moggi-Cecchi says.
Moggi-Cecchi and his fellow archaeologists entered the cave through a long shaft, and from there they used a portable X-Ray machine and high-res video probes to fully observe the Neanderthal's skull.
Teething problems — From their observations, the researchers were able to piece together 80 percent of the Neanderthal's dental records. And this ancient human could have done with a trip to the dentist.
Through the alveolar bone, researchers found the Neanderthal suffered from periodontal disease — a gum problem that can cause gingivitis and tooth loss, as happened with this poor ancient fellow.
But perhaps surprisingly, the Neanderthal had pretty decent dental hygiene. The periodontal disease wasn't severe, and at least four of the missing teeth were lost after the Neanderthal had already died.
The scientists also identified some typical characteristics to re-confirm the fact that this skull belonged to a Neanderthal which lived some 150,000 years ago. And they worked out the specimen's general age, finding it was an adult, although not a senior citizen, at the time of death.
"We observed features that confirmed the attribution of the specimen to Neanderthals, such as the existence of a space behind the third molar, a distinctive Neanderthal feature, of no functional significance," Moggi-Cecchi says.
Digging Deep — Curiously, one of the most surprising discoveries the researchers made is eerily familiar to us modern-day humans. In a close examination of the Neanderthal's skull, the researchers found a human-like feature — the palatine torus.
The palatine torus is a variation on skull structure commonly found in Homo sapiens — but not Neanderthals. This study is the first reported discovery of the palatine torus in Neanderthals.
"Palatine torus is an anatomical variant of the skull also found in modern human populations, but with low occurrence in fossil specimens," Moggi-Cecchi says.
The palatine torus is essentially a harmless bone growth that occurs on the roof of the mouth. Typically, the roof of our mouth is smooth and hard, but at least 20 percent of people in the United States have this benign growth. The percentage of the global population with a palatine torus is hard to say for certain, but it appears to be more common among Asians, Native Americans, and Norwegians.
Common issues resulting from this extra bone include speech impediments and difficulty chewing or swallowing, but most people with palatine torus don't need treatment for it.
It seems at least some ancient humans had this same unusual feature, too. But before we assume that scientists have found another missing link between Neanderthals and humans, you might want to pump the brakes. There is still much we don't know about our connection to this ancient human species.
"Its well-expressed occurrence is now reported in the Altamura specimen and in Neanderthals for the first time, but it does not affect our understanding of the connection between Neanderthals and modern humans," Moggi-Cecchi says.
Abstract: The Neanderthal specimen from Lamalunga Cave, near Altamura (Apulia,Italy), was discovered during a speleological survey in 1993. The specimen is one of the most complete fossil hominins in Europe and its state of preservation is exceptional, although it is stuck in calcareous concretions and the bones are mostly covered by calcite depositions. Nevertheless, it is possible to carry out some observations on craniodental features that have not previously been described. In this work, we present an account of the oral cavity, made possible by the use of a videoscope, which allowed us to reach some hidden parts of the mandible and palate. This is the first detailed overview of the teeth and maxillary bones of the Neanderthal skeleton from Altamura. The dentition is almost complete. However, two teeth (upper right P3 and upper left M1) were lost antemortem and four teeth (lower right I1and P3 and lower left I1 and I2) were lost most probably post mortem. Dental wear is marked. The erupted M3s and the inversion of the compensating curve of Wilson in the M1s and M2s but not in theM3s suggest that the individual is fully adult, but not old. Although most of the teeth have their roots exposed for several millimeters, the periodontal bone appears to be in good condition overall, except in correspondence of the two ante-mortem tooth losses. X-rays of the anterior teeth show a periapicallesion, probably linked to the advanced dentalwear. We also observed a weak expression of taurodontism in the posterior dentition and thepresence of a retro molar space, features consistent with an attribution to the Neanderthal hypodigm; this attribution is also supported by aspects of the cranial morphology, the morphometric analysis of the scapula and preliminary mtDNA data. There is also a well-developed palatine torus, to the best of our knowledge a feature not previously described in Neanderthals.