Most archaeological and fossil teeth are heavily worn, and this greatly limits the usefulness of tooth crown diameter measurements, as they are usually defined at the widest points of the crown. There are alternatives, particularly measurements at the cervix of the tooth, where the crown joints the root, and measurements along a diagonal axis in molars, that are much less affected by wear. These would allow a wider range of specimens to be included, e.g., in the study of dental reduction in Upper Palaeolithic and Mesolithic Homo sapiens. In addition, they would allow the little-worn teeth of children to be compared directly with well-worn teeth in adults. These alternatives, however, have been little used, and as yet there have not been any studies of the repeatability with which they can be measured, or of the extent to which they are related to the more usual crown diameters. The present study is based on a group of unworn teeth, where direct comparisons could be made between the alternative measurements, which are not much affected by wear, with the usual crown diameters, which are very much affected. In an interobserver-error study of this material, cervical and diagonal measurements could be recorded as reliably as the usual crown diameters. The buccolingual cervical measurement was strongly correlated with the normal bucclingual crown diameter in all teeth, whereas the mesiodistal cervical measurement was highly correlated with the normal mesiodistal crown diameter in incisors and canines, but less so in premolars and molars. The molar diagonal measurements showed high correlations with all other measurements. Crown areas (robustness index) calculated from the usual diameters were strongly correlated with crown areas calculated from cervical measurements, and crown areas calculated from molar diagonals were strongly correlated with both other areas. Despite the long usage of the more usual maximum crown diameters, the alternative dental measurements could be measured just as reliably, could record similar information about tooth crown size, and would be better measures for the worn dentitions seen in archaeological and fossil material.

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.

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Methods of measuring tissue area from images of longitudinal thin tooth sections have been used to assess sexual dimorphism in the permanent dentition. The aim of this study was to demonstrate the extent of sexual dimorphism within the coronal tissue proportions of permanent mandibular canines and premolars, using area measurements of the enamel and dentine-pulp core. The sample consisted of embedded "half-tooth" sections from 45 individuals, all of known age-at-death and sex, collected from the St. Thomas' Anglican Church historic (1821-1874) cemetery site in Belleville, ON, Canada. The relative dentine-pulp area of the third premolars and canines displayed high levels of sexual dimorphism, as well as statistically significant mean differences between the sexes. The male canines and premolars have significantly more dentine than their female counterparts, as well as relatively more dentine with respect to overall crown size. The female canines and premolars have significantly more enamel relative to overall crown area than those of the males. These results suggest that relative area measures of crown tissues are more predictable measures of sexual dimorphism than absolute measures, and tissue proportions may remain constant despite intrasex variation in overall tooth crown size.

One of the difficulties that has prevented Wilson bands, internal defects of enamel growth, from achieving maximum usefulness as indicators of stress in bioarchaeological studies is the inaccuracy of the methods for determining ages of defect occurrence. This study tests a technique that uses microstructural growth markers of enamel to establish the chronology of Wilson bands in deciduous teeth. A sample of 274 teeth from 127 subadults from an Imperial Roman necropolis was sectioned and examined under a microscope. The sample ranged in age at death from birth to 13 years. Sixty-four teeth from 50 individuals were found to have 447 Wilson bands in total. Of those contributing multiple teeth to the sample, 13 individuals had at least one Wilson band in each of two teeth that could be identified as having been formed coevally. These provided the basis for testing the methodology. Paired t-tests found no significant differences between the chronologies of matched pairs in the two teeth, with mean ages from each differing by less than 1 day. The authors propose a hypothesis that explains the development of Wilson bands, and classifies them within the context of other features of enamel. The most important implications arising from this paper are: 1) aging methods using microstructural growth markers can be applied to deciduous teeth; 2) physiological stressors leave different traces in enamel, depending on severity and time of occurrence relative to total crown development; 3) no threshold level exists; all physiological stress will leave a record; 4) therefore, no minimal definition of a Wilson band can be delineated that recognizes all such events; 5) implying that studies using them will only identify minimum rates of occurrence.