Dentistry is confronted with the functional and aesthetic consequences that result from an increased prevalence of misaligned and discrepant dental occlusal relations in modern industrialised ...societies. Previous studies have indicated that a reduction in jaw size in response to softer and more heavily processed foods during and following the Industrial Revolution (1,700 CE to present) was an important factor in increased levels of poor dental occlusion. The functional demands placed on the masticatory system play a crucial role in jaw ontogenetic development; however, the way in which chewing behaviours changed in response to the consumption of softer foods during this period remains poorly understood. Here we show that eating more heavily processed food has radically transformed occlusal power stroke kinematics. Results of virtual 3D analysis of the dental macrowear patterns of molars in 104 individuals dating to the Industrial Revolution (1,700-1,900 CE), and 130 of their medieval and early post-medieval antecedents (1,100-1,700 CE) revealed changes in masticatory behaviour that occurred during the early stages of the transition towards eating more heavily processed foods. The industrial-era groups examined chewed with a reduced transverse component of jaw movement. These results show a diminished sequence of occlusal contacts indicating that a dental revolution has taken place in modern times, involving a dramatic shift in the way in which teeth occlude and wear during mastication. Molar macrowear suggests a close connection between progressive changes in chewing since the industrialization of food production and an increase in the prevalence of poor dental occlusion in modern societies.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The earliest anatomically modern humans in Europe are thought to have appeared around 43,000-42,000 calendar years before present (43-42 kyr cal BP), by association with Aurignacian sites and lithic ...assemblages assumed to have been made by modern humans rather than by Neanderthals. However, the actual physical evidence for modern humans is extremely rare, and direct dates reach no farther back than about 41-39 kyr cal BP, leaving a gap. Here we show, using stratigraphic, chronological and archaeological data, that a fragment of human maxilla from the Kent's Cavern site, UK, dates to the earlier period. The maxilla (KC4), which was excavated in 1927, was initially diagnosed as Upper Palaeolithic modern human. In 1989, it was directly radiocarbon dated by accelerator mass spectrometry to 36.4-34.7 kyr cal BP. Using a Bayesian analysis of new ultrafiltered bone collagen dates in an ordered stratigraphic sequence at the site, we show that this date is a considerable underestimate. Instead, KC4 dates to 44.2-41.5 kyr cal BP. This makes it older than any other equivalently dated modern human specimen and directly contemporary with the latest European Neanderthals, thus making its taxonomic attribution crucial. We also show that in 13 dental traits KC4 possesses modern human rather than Neanderthal characteristics; three other traits show Neanderthal affinities and a further seven are ambiguous. KC4 therefore represents the oldest known anatomically modern human fossil in northwestern Europe, fills a key gap between the earliest dated Aurignacian remains and the earliest human skeletal remains, and demonstrates the wide and rapid dispersal of early modern humans across Europe more than 40 kyr ago.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The Anterior Dental Loading Hypothesis states that the unique Neanderthal facial and dental anatomy was an adaptive response to the regular application of heavy forces resulting from both the ...masticatory and cultural use of the anterior teeth. Heavy anterior tooth wear frequently observed in Neanderthal specimens is cited as a main source of evidence for heavy forces being applied to these teeth. From this, it might be predicted that the wear shown on the anterior teeth of Neanderthals would greatly exceed that of the posterior teeth and that this differential would be greater than in other hominins with different facial morphologies.
In this paper, a new method of examining tooth wear patterns is used to test these predictions in a large assemblage of Late Pleistocene hominins and a group of recent hunter–gatherers from Igloolik, Canada. The results show that all Late Pleistocene hominins, including Neanderthals, had heavily worn anterior teeth relative to their posterior teeth but, contrary to expectations, this was more pronounced in the modern humans than in the Neanderthals. The Igloolik Inuit showed heavier anterior tooth wear relative to their posterior teeth than any Late Pleistocene hominins. There was, however, a characteristic Neanderthal pattern in which wear was more evenly spread between anterior teeth than in modern humans. Overall, the evidence presented here suggests that all Late Pleistocene hominins habitually applied heavy forces between their anterior teeth and that Neanderthals were not exceptional in this regard. These results therefore does not support the Anterior Dental Loading Hypothesis.
As one of today’s major oral health issues, periodontal disease affects populations worldwide. Here, methods used to record its past prevalence are reviewed, including the problems associated with ...the use of measurements to record bone loss. Clinical and bioarchaeological research offers strong support for the Kerr method that records interdental septum morphological changes as a means of identifying gingivitis and periodontal disease. Using Kerr’s approach, four assemblages from Sudan dating to the Neolithic, Kerma and Medieval periods are examined to track the progression of the disease through time. Results show a significantly lower prevalence of periodontal disease and a limited distribution across the mouth in the Neolithic period. Significant differences were found between the sexes at the Medieval sites, which were not present at the Neolithic and Kerma sites. With no patient history and the cumulative effects of a dynamic and episodic disease - only a snapshot of which is captured at death - the concept of ‘oral health’ may be hard to apply in archaeological remains. As suggested by Kerr, it at best provides an insight into the periodontal status at death. Here, this ‘snapshot’ reveals differences across the mouth, over time and between sexes.
Food has long served as a mechanism for identifying and reinforcing social structures, but while carbon and nitrogen isotope analysis has provided important identity-based evidence of past diets, the ...cyclical and stable/fluid nature of food consumption practices across the life course has been relatively neglected. In this paper, the large human assemblage at Çatalhöyük with all age groups present has enabled diet reconstruction of the rarely represented groups of older children and adolescents as well as for the young, middle and old adult age groups of both sexes. These data show how neonates reflect foods available to pregnant mothers, that infants were breastfed until around 18 months of age and weaned by three years of age, older children had a different diet compared to adolescents and young adults who, in turn, differed from middle and older adults. The absence of sex-related differences suggests changes in food consumed at Çatalhöyük accompanied the marking of transitions through the life course.
Archaeological discoveries of teeth provide remarkable information on humans, animals and the health, hygiene and diet of ancient communities. In this fully revised and updated 2005 edition of his ...seminal text, Simon Hillson draws together a mass of material from archaeology, anthropology and related disciplines to provide a comprehensive manual on the study of teeth. The range of mammals examined has been extended to include descriptions and line drawings for 325 mammal genera from Europe, North Africa, western, central and northeastern Asia, and North America. The book also introduces dental anatomy and the microscopic structure of dental tissues, explores how the age or season of death is estimated and looks at variations in tooth size and shape. With its detailed descriptions of the techniques and equipment used and its provision of tables and charts, this book is essential reading for students of archaeology, zoology and dental science.
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