The earliest evidence for anatomically modern humans in northwestern Europe.

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.

Deciduous tooth growth in an ancient Greek infant cemetery.

The Kylindra cemetery on Astypalaia in the Dodecanese, in use 750 BC to 1st century AD, contains a unique skeletal collection. Over 2,400 infant inhumations, each buried in its own clay pot, have been uncovered so far. The skeletal material from each burial is embedded within a ball of accreted earth and since 2001, some 850 infant remains have been recovered and conserved. Most of these died perinatally, but some were very premature babies and some appear to have survived for several months after birth. A study to estimate ages at death of 277 teeth from 107 infants, using microstructural growth markers, is currently underway. One immediate objective is to help resolve the enigma of why such an unusually large number of infants were interred on such a remote Aegean island. Longer term objectives are to reconstruct the sequences of development of the different deciduous tooth types, providing new standards of growth for long bones, the skull and the dentition. This paper presents an interim report on the findings from the histological study, which has analysed 68 teeth from 36 individuals so far. Five of the 36 infants survived birth, three dying within the first 3 weeks of life and the other two surviving for about 3 months. Average appositional growth rates were found to be 3.6 microm/day, and initial mineralisation was found to be well below the figures in Sunderland and coworkers' study in 1987.

Sexual dimorphism of the dental tissues in human permanent mandibular canines and third premolars.

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.

Health of infants in an Imperial Roman skeletal sample: perspective from dental microstructure.

This study examines general health in the first year of life of a population of 127 subadults from the Imperial Roman necropolis of Isola Sacra (2nd-3rd century ACE). Health status was determined by analyzing 274 deciduous teeth from these children for Wilson bands (also known as accentuated striae), microscopic defects caused by a disruption to normal enamel development arising from some generalized external stressor. While macroscopic enamel defects, or hypoplasias, have long been used as proxies of general population health, we believe that this is the first population-wide study of microscopic defects in deciduous teeth. We used microstructural markers of enamel to attach very precise chronologies to Wilson band formation that allowed us to calculate maximum prevalence (MAP) and smoothed maximum prevalence (SMAP) distributions to portray what we believe to be a realistic risk profile for a past population of children. There appear to be two periods of high prevalence, the first beginning around age 2 months and continuing through month 5, and the second higher period beginning around month 6 and continuing through month 9. These results are discussed in light of historical records of Roman childhood rearing practices.

Alternative dental measurements: proposals and relationships with other measurements.

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.

Test of histological methods of determining chronology of accentuated striae in deciduous teeth.

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.

Laboratory monitoring of OxyContin (oxycodone): clinical pitfalls.

Some patients have headaches that are refractory to standard treatments, and they require chronic administration of opioid analgesics. The use of opioids in a clinical setting must be closely monitored due to the medications' potential for addiction, abuse, and fatal interactions. Limited access to opioids and the demand for them outside the clinical setting leads to another danger. Patients can mislead their providers into prescribing opioids, intending to sell the medications instead of using them to alleviate their own pain. For protection of the patient, as well as the community, it is vital that such activity be prevented. We recently encountered a patient we suspected of abusing or misusing OxyContin (oxycodone). In order to determine whether the patient was taking the medication as prescribed, we ordered a urine-based immunoassay drug screen. The results were negative; the patient appeared to not have oxycodone in his system. Based on these results, we dismissed the patient from our practice. At the patient's request, a second test was performed, this time using gas chromatography-mass spectrometry. It indicated that the patient did indeed have sufficiently high levels of oxycodone in the urine. The minimum level threshold was too high to detect the presence of oxycodone in the immunoassay. We would like to help prevent future misunderstandings such as we experienced. To do so, we will first present the case of our patient, followed by a discussion of the actions taken. Finally, we will provide an overview of analgesic monitoring systems.