(2017) The morphology of the enamel-dentine junction in Neanderthal molars: Gross morphology, non-metric traits, and temporal trends. Journal of Human Evolution, Abstract: This study explores the morphological differences between the enamel-dentine junction (EDJ) of maxillary and mandibular molars of Neanderthals (n = 150) and recent modern humans (n = 106), and between an earlier Neanderthal sample (consisting of Pre-Eemian and Eemian Neanderthals dating to before 115 ka) and a later Neanderthal sample (consisting of Post-Eemian Neanderthals dating to after 115 ka). The EDJ was visualised by segmenting microtomographic scans of each molar. A geometric morphometric methodology compared the positioning of the dentine horns, the shape of the marginal ridge between the dentine horns, and the shape of the cervix. We also examined the manifestation of nonmetric traits at the EDJ including the crista obliqua, cusp 5, and postparacone tubercle. Furthermore, we report on additional morphological features including centrally placed dentine horn tips and twinned dentine horns. Our results indicate that EDJ morphology can discriminate with a high degree of reliability between Neanderthals and recent modern humans at every molar position, and discriminate between the earlier and the later Neanderthal samples at every molar position, except for the M3 in shape space. The cervix in isolation can also discriminate between Neanderthals and recent modern humans, except at the M3 in form space and is effective at discriminating between the earlier and the later Neanderthal samples, except at the M2/M2 in form space. In addition to demonstrating the taxonomic valence of the EDJ, our analysis reveals unique manifestations of dental traits in Neanderthals and expanded levels of trait variation that have implications for trait definitions and scoring.Dear Mike, Ià à à à à à à à à à à à àIà à à à à à with the copy-edits. Kind regards, MattDetailed This study explores the morphological differences between the enamel-dentine junction (EDJ) of 2 maxillary and mandibular molars of Neanderthals (n = 150) and recent modern humans (n = 106), 3and between an earlier Neanderthal sample (consisting of Pre-Eemian and Eemian Neanderthals 4 dating to before 115 ka) and a later Neanderthal sample (consisting of Post-Eemian Neanderthals 5 dating to after 115 ka). The EDJ was visualised by segmenting microtomographic scans of each 6 molar. A geometric morphometric methodology compared the positioning of the dentine horns, the 7 shape of the marginal ridge between the dentine horns, and the shape of the cervix. We also 8 examined the manifestation of non-metric traits at the EDJ including the crista obliqua, cusp 5, and 9 post-paracone tubercle. Furthermore, we report on additional morphological features including 10 centrally placed dentine horn tips and twinned dentine horns. Our results indicate that EDJ 11 morphology can discriminate with a high degree of reliability between Neanderthals and recent 12 modern humans at every molar position, and ...

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Study Design: Prospective within-subject experimental design using a sample of convenience. Objectives: To describe cervical foraminal dimensions in vivo of nonimpaired, asymptomatic individuals in a neutral cervical spine position using magnetic resonance images, and then to document dimensional changes of the foramina when placing the neck in a retracted position. Background: Physical therapists frequently use movement interventions to treat spine dysfunction. The influence of positional changes of the head and neck on the dimensions of the cervical neural foramina is not well documented. Methods and Measures: Twenty asymptomatic subjects (10 men and 10 women), 22 to 25 years of age (mean ± SD = 23.7 ± 0.8), underwent magnetic resonance imaging of the cervical spine in both neutral and retracted positions. Bilateral measurements were documented in both positions and compared for height, width, and area of each subject's intervertebral foramen from C2-C3 to C7-T1. Results: No significant differences (P Ͼ 0.004) were found between the 2 neck positions. With the single exception of foraminal area at C3-C4, the mean values of height, width, and area in the retracted position were equal to or larger than those of the cervical neutral position. Conclusions: Therapeutic maneuvers using retraction of the cervical spine do not promote positional stenosis of the intervertebral foramen in the healthy neck.