The usefulness of caries frequency,depth, and location in determining cariogenicity and past subsistence: A test on early and later agriculturalists from the Peruvian coast

Dental markers have been used to unravel particularities of paleodiet, subsistence, social structure, and health. This article aims to compare oral pathology among four pre‐Columbian groups with different degrees of agricultural and socio‐cultural development but comparable ecological conditions who lived on the coastal desert of Peru. Three of these groups are assigned to distinct phases of the Formative Period (2500–1 BC), a time critical for our understanding of the development of agriculture and social complexity. The fourth group corresponds to the Late Intermediate Period (1000–1470 AD), when agriculture had its apogee and society was highly stratified. In this study we test whether there is an increase (1) in the frequency of carious lesions and (2) in caries depth, and (3) if there is a shift from occlusal to extra‐occlusal caries locations with the development of agriculture. Therefore, we analyze the frequencies of carious lesions and antemortem tooth loss (AMTL), the caries distributions by age, sex, and type of tooth, as well as the tissues affected by, and the location of the carious lesions. Since there are no significant differences in the frequencies of carious lesions and AMTL between the groups, we reject hypothesis 1. In contrast, caries depth does increase, and caries location changes from occlusal to extra‐occlusal sites with agricultural development. However, we can only corroborate hypothesis 2 and 3 when taking into consideration dental wear. Thus, we recommend that caries depth and locations should be used with evaluations of dental wear to reconstruct subsistence in ancient populations. Am J Phys Anthropol 143:75–91, 2010. © 2010 Wiley‐Liss, Inc.     

Age estimation of the White rhinoceros (Ceratotherium simum)

Age estimation criteria for the southern White rhinoceros ( Ceratotherium simum simum ) are presented both for free-ranging live animals and for cranial material. These are based on: (i) size appearance and horn development of live animals; (ii) stages of tooth eruption; (iii) tooth wear classes; (iv) attrition in height of the first molar tooth; (v) counts of cementum lines visible in tooth sections. Selected measurements are presented for live animals, skulls and horns.
For live animals, eight size classes are distinguished, seven of these covering immature animals up to ten years of age. Sixteen tooth wear classes are established, based on eruption and surface wear of maxillary dentition. Chronological ages were assigned from individually known animals followed in the field, and from skulls from animals for which exact records of age were available, or which could be assigned to an age category from appearance at death. Cementum line counts corresponded approximately with age in years, despite difficulties in interpreting lines. Some variability was observed, possibly related to nutritional conditions.
The maximum cementum line count obtained indicates a longevity of at least 40 years. Full body weight and socio-sexual maturity are attained by males between 10 and 15 years of age, while females first give birth between six and eight years of age. Sequences and times of tooth eruption are similar to those reported for the Black rhinoceros ( Diceros bicornis ).
Comparative cranial and body measurements are presented for the northern subspecies ( Ceratotherium simum cottoni ).     

Tooth wear and compensatory modification of the anterior dentoalveolar complex in humans

In populations living in environments where teeth wear severely, some compensatory modification of the dentoalveolar complex is thought to occur during life whereby functional occlusion is maintained as tooth substance is lost by wear. This study investigates one aspect of this modification process: Changes in the anterior dentoalveolar complex that are accompanied with wear were examined in a series of Japanese skeletal samples. In the prehistoric Japanese hunter-gatherer population heavy wear occurs over the entire dentition. The following changes were demonstrated to have occurred in the anterior segment of the dentition accompanied by wear on the anterior teeth: The anterior teeth tip lingually with wear up to a nearly upright position to fill in interproximal spaces that would have been generated by wear, and to maintain contact relations between adjacent teeth. At the same time, the anterior surface of the maxillary alveolar process also inclines lingually to a certain extent. The amount of lingual tipping is greater in the maxillary anterior teeth than in their mandibular antagonists. It is because of this discrepancy that, with age, the horizontal component of the overlap between maxillary and mandibular anterior teeth decreases, and their bite form changes from scissor bite to edge-to-edge bite. Lesser degrees of lingual tipping of the anterior teeth were also detected in the prehistoric agriculturists and historic Japanese populations. The variation in the degree of lingual tipping observed among the samples is explained by inter-population variation in severity and pattern of tooth wear. This and other evidence suggests that mechanisms that compensate for wear in the anterior dentition may be characteristic of all living human populations, independently of the degree of wear severity endured in their environments.     

Palaeopathology of the Pleistocene specimen D2600 from Dmanisi (Republic of Georgia)

Here we present a detailed palaeopathological study of the hominin mandible D2600 recovered at the Dmanisi site, Republic of Georgia. The Dmanisi assemblage represents the earliest evidence of hominins outside Africa with an age of 1.8 Ma. D2600 is the holotype of Homo georgicus species and its taxonomic assignment is still under debate. Our study reveals severe and unusual dental wear accompanied of extensive root exposure and dental axial migration, periapical abscesses and enamel fractures. In addition, there is evidence of post-eruptive tooth rotation and temporomandibular arthropathy. We propose that the wear pattern observed in this individual is related to a diet with a high intake of fibrous and abrasive foods such as fruits and plants, as it is usually recorded in chimpanzees and gorillas and unlike the wear pattern observed in other Homo specimens of our comparative sample. The rounded occlusal surfaces and highly polished labio-lingual surfaces of D2600 anterior teeth could be mainly the consequence of pre- and/or para-masticatory activities such as gripping and stripping. This type of food would be also the origin of the highly cupped occlusal morphology of the posterior dentition in combination with relatively slight approximal attrition. However, the lesions exhibited by D2600 have not significantly altered the morphology of the mandible and do not prevent a proper taxonomic assessment.     

Dental caries in a Portuguese identified skeletal sample from the late 19th and early 20th centuries

Dental caries was investigated in 600 adult dentitions belonging to the identified osteological collections of the Museum of Anthropology, University of Coimbra, Portugal (late 19th/early 20th centuries). The main advantage of this sample compared to an archaeological source is the presence of known demographic parameters such as age, sex, and occupation. The aim of this study is to investigate the issues involved in comparing caries data derived from archaeological death assemblages with statistics compiled from clinical studies of the living. When only the upper dentition was considered, higher rates were observed in females than in males. No differences were found between sexes for lower teeth. In both sexes, both the percentage of carious teeth and the severity of lesions were found to increase with age, demonstrating that caries activity continued throughout life. The slight decrease observed for the age group 70–79 years is probably due to the increased antemortem tooth loss in the elderly. Caries was most common at contact areas (32.9%) and rarest at smooth crown surfaces (6.5%). Root surface caries was graphed in relation to the exposure of roots, and it was confirmed that the degree of root exposure was not strongly related to the frequency of carious lesions on the exposed root surface, although both increased with age. Molars were attacked more frequently by caries as a whole than premolars, canines or incisors. The results are similar to studies of recent living populations with a limited access to professional dental care. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.     

Ontogenetic changes in limb bone structural proportions in mountain gorillas (Gorilla beringei beringei)

Behavioral studies indicate that adult mountain gorillas (Gorilla beringei) are the most terrestrial of all nonhuman hominoids, but that infant mountain gorillas are much more arboreal. Here we examine ontogenetic changes in diaphyseal strength and length of the femur, tibia, humerus, radius, and ulna in 30 Virunga mountain gorillas, including 18 immature specimens and 12 adults. Comparisons are also made with 14 adult western lowland gorillas (Gorilla gorilla gorilla), which are known to be more arboreal than adult mountain gorillas. Infant mountain gorillas have significantly stronger forelimbs relative to hind limbs than older juveniles and adults, but are nonsignificantly different from western lowland gorilla adults. The change in inter-limb strength proportions is abrupt at about two years of age, corresponding to the documented transition to committed terrestrial quadrupedalism in mountain gorillas. The one exception is the ulna, which shows a gradual increase in strength relative to the radius and other long bones during development, possibly corresponding to the gradual adoption of stereotypical fully pronated knuckle-walking in older juvenile gorillas. Inter-limb bone length proportions show a contrasting developmental pattern, with hind limb/forelimb length declining rapidly from birth to five months of age, and then showing no consistent change through adulthood. The very early change in length proportions, prior to significant independent locomotion, may be related to the need for relatively long forelimbs for climbing in a large-bodied hominoid. Virunga mountain gorilla older juveniles and adults have equal or longer forelimb relative to hind limb bones than western lowland adults. These findings indicate that both ontogenetically and among closely related species of Gorilla, long bone strength proportions better reflect actual locomotor behavior than bone length proportions.     

Dental pathologies in ten free-ranging chimpanzees from Gombe National Park, Tanzania

The dental remains of ten adult chimpanzees from Gombe National Park, Tanzania, were examined for enamel attrition, caries, abscesses, periodontal disease, and tooth loss. Age was the underlying factor in the development of dental pathology, in that enamel wear was present to some extent in all ten but was uniformly severe only in the three for whom estimated age at death was 39-43 years. In turn, enamel wear appears to have been the direct cause of abscess development, periodontal disease, and tooth loss. Periodontal disease was commonly expressed as alveolar resorption, particularly around the premolars and molars. This involvement was variable in all except the two youngest. Some interesting wear patterns were evident in the form of deep grooves in the upper incisors and dramatic notching of the lower canines. These patterns, and enamel attrition in general, were attributed to normal mastication and to various stripping activities. Only one carious lesion was observed, in a male with an estimated age of 26 years. An accurate assessment of the actual prevalence of caries was obscured by enamel wear and tooth loss in the older individuals.     

Dento-alveolar lesions and nutritional habits of a Roman Imperial age population (1st–4th c. AD): Quadrella (Molise, Italy)

The study of teeth is very important in archaeoanthropology for reconstruction of the nutritional habits and living conditions of past populations. We have analysed dental lesions of pathological (caries, abscesses and ante mortem tooth loss) and non-pathological origin (calculus), linear enamel hypoplasia and tooth wear in 67 adults from the Roman Imperial age necropolis (1st-4th c. AD) of Quadrella (Molise, Italy). The high frequency of caries (likely giving rise to the abscesses and ante mortem tooth loss), the abundant calculus and the low frequency of heavy wear are probably due to a limited use of hard fibrous foods and a high consumption of carbohydrates. The high frequency of linear enamel hypoplasia suggests metabolic problems during growth. Comparison of these data with those for two coeval Italian necropoleis near Rome (Latium), Isola Sacra and Lucus Feroniae, indicates poorer living conditions in the Quadrella population.     

A new juvenile specimen of Yunnanosaurus robustus (Dinosauria: Sauropodomorpha) from Early to Middle Jurassic of Chuxiong Autonomous Prefecture,Yunnan Province,China

An almost complete skeleton with partial cranial material (ZMNH-M8739) is recovered from the Early or Middle Jurassic of southwest China. ZMNH-M8739 is identified as a juvenile individual of basal sauropodomorph dinosaur, Yunnanosaurus robustus Young, 1951. The revised diagnoses are as follows: absence of anteroposterior expansion on the medial end of astragalus and dorsoventrally compressed medium shaft of the metatarsal IV. Unfused neural arch and finely grooved long bone surface texture indicate that this individual is in the immature growth stage. ZMNH-M8739 possesses the tooth–tooth wear facet on its mesial maxillary and dentary teeth. However, the distal maxillary teeth have coarse serrations. Such a characteristic dentition could represent a unique feeding mechanism of this animal. Finally, ZMNH-M8739 constitutes a monophyletic group with Y. robustus (holotype), and Y. huangi is nesting this clade in the phylogenetic tree of the present analysis. Comparison of juvenile and adult specimen reveals distinctive growth changes of Y. robustus. This clade is positioned in an unnamed clade at a sister taxon of Sauropoda. Finally, some members of the so-called prosauropod dinosaurs constitute a monophyletic group in the present result.     

Capillaria hepatica (Nematoda) infections in human-habituated mountain gorillas (Gorilla gorilla beringei) of the Parc National de Volcans, Rwanda

Habituation to humans of free-ranging populations of endangered mountain gorillas (Gorilla gorilla beringei) raised concern of anthropozoonotic transmission of parasitic helminths and protozoans. Examinations of liver tissue of 19 gorillas found dead in the Parc National de Volcans, Rwanda, revealed 10 cases of hepatic nematodiasis due to Capillaria hepatica. Identifiable C. hepatica eggs were present in the liver of 4 gorillas (3 juveniles, 1 adult), and nematode cross-sections were found in 1 juvenile gorilla. Six other adult gorillas had areas of periportal and subcapsular fibrosis with calcified eggs. Histologically, the lesions surrounded by the areas of mild inflammatory reaction were characterized by subcapsular, periportal foci of fibrosis in which were embedded numerous C. hepatica eggs. Control of hepatic capillariasis in the remaining populations of mountain gorillas should be focused on eradication or control of populations of rodent pests (i.e., mice and rats) that sustain the reservoir of C. hepatica in habitats shared by gorillas and humans.     

Analysis of human skeletal remains from Nadin iron age burial mound

This analysis attempts to reconstruct health, disease and life conditions of the population buried in Nadin, a burial mound, situated in central Dalmatia, Croatia. The analyzed skeletal material belongs to Liburnian culture and could be dated to early Iron Age, from 9th to 6th century B.C. The sample consists of a minimum number of 37 individuals, 7 children and 30 adults. The frequency of all the observed conditions is relatively low. Cribra orbitalia was observed only in females, the frequency of periosteal reaction on the tibiae is 26.1%. Two cases of cranial trauma were observed. Analyzed teeth exhibit low prevalence of carious lesions, ante mortem tooth loss and linear enamel hypoplasia. The case of hyperostosis frontalis interna on the endocranial surface of the frontal bone was observed. The affected skull belongs to the older adult female.     

Skeletal evidence of trauma in African apes, with special reference to the gombe chimpanzees

Incidence of cranial and postcranial skeletal trauma was investigated in samples of chimpanzees (Pan troglodytes troglodytes, P. troglodytes schweinfurthii), lowland gorillas (Gorilla gorilla gorilla), and bonobos (P. paniscus). The larger (adult) samples of chimpanzees (N=127 crania, 92 postcrania) and gorillas (N=136 crania, 62 postcrania) are curated at the Powell-Cotton Museum, Birchington, U.K. The bonobo collection (N=71 crania, 15 postcrania) is housed the Musée Royal de l'Afrique Centrale in Tervuren, Belgium. In addition, data were collected on the small but extremely well-documented skeletal sample from Gombe National Park (N=14 crania, 13 postcrania — including adults and adolescents). Cranial injuries, including healed fractures and bite wounds, were fairly frequent in the museum collection of chimpanzees (5.5% of individuals), but were twice as frequent in gorillas (11.0%). In the Gombe sample an even higher incidence was observed (28.6% of individuals). Bonobos, however, showed the lowest incidence of cranial trauma found among any of the African ape samples (1.4% of individuals). Postcranial trauma, documented most clearly by healed fractures, was seen in 21.7% of the Powell-Cotton chimpanzees, 30.8% of Gombe chimpanzees, 17.7% of gorillas, and in 13.3% of bonobos. Most of these lesions were found in the upper appendage. Nevertheless, highly debilitating healed fractures of the femur were also noted, most frequently and severe in female gorillas. The pattern of injuries suggests serious risks of falling in all free-ranging African apes, but also (in chimpanzees and gorillas) considerable risk from interindividual aggression, especially for males.     

Revision of Habrosaurus Gilmore (Caudata; Sirenidae) and relationships among sirenid salamanders

The sirenid salamander Habrosaurus is revised and redescribed based on skull elements and vertebrae from the middle Campanian–middle Palaeocene of the North American Western Interior. Habrosaurus differs from the Cenozoic (Eocene–Recent) sirenids Siren and Pseudobranchus in a suite of cranial and vertebral plesiomorphies, one vertebral character of uncertain polarity and five apomorphies describing the structure of the dentary, atlas and tooth crowns. Two species are identified based on dental characters: the type species H. dilatus (late Maastrichtian–middle Palaeocene) has stout marginal and palatal teeth with bulbous crowns and prominent wear facets, whereas H. prodilatus sp. nov. (middle Campanian) has chisel-like marginal teeth (palatal teeth unknown) with weaker wear facets. Habrosaurus is argued to be the geologically oldest, undoubted sirenid and the sister-taxon of Siren  +  Pseudobranchus . Replacement of marginal teeth with a broad, horny beak in Siren and Pseudobranchus and the broad, bulbous marginal and palatal teeth in H. dilatus are proposed to be convergent strategies for achieving a crushing bite. The chisel-like teeth of H. prodilatus are interpreted as being transitional to the more specialized, crushing dentition of H. dilatus .     

Experimental studies in human tooth wear. II

Studies of human tooth wear have been carried on for the past two years using a machine designed to approximate human chewing motions. During this time wear patterns that resemble those frequently found on the teeth of various American Indian skulls have been produced on casts of the definition. Noticeably among these patterns produced are examples of wear on the front end of the dental arches that result in an edge to edge bite. This type of wear was produced by wearing down casts of a modern dentition with a “normal” overbite. The forces applied to the casts mounted on the machine are variable over a wide range and numerous force combinations are possible. By noting these forces and the resulting vectors, the motions necessary to produce different wear patterns can be determined. This has especially aided in understanding the ways in which the oblique molar wear is produced.     

The role of occlusal stress and gingival infection in the formation of exostoses on mandible and maxilla from Neolithic China

Exostoses on the mandible and maxilla is a frequently observed bone growth of controversial aetiology. The aim of this study is to analyse environmental factors that may stimulate the formation of exostoses on different regions of the maxilla and mandible. Sixty-six well-preserved crania from Neolithic China were studied for the presence of buccal exostoses on the maxilla (BE) and lingual exostoses on the mandible (LME). Other oral health indicators, such as occlusal wear on molars, pathology of temporomandibular joint (TMJ), carious lesions, calculus accretion, periodontal disease, and antemortem tooth loss were recorded. Buccal maxillary exostosis was unusually common on the Neolithic skulls from China, which thus resemble the Sinantropus crania described by Weidenreich (1943). We report a significant Spearman correlation between BE and LME (rho = 0.54, P < 0.00001), suggesting a partially shared aetiology of these two types of exostoses. The highest correlations between either form of exostoses and any oral indicator of stress were found for pathology at TMJ (rho = 0.46, P < 0.0001 for both types of exostoses). Smaller but significant correlations were observed between LME and the age adjusted wear rate on lower molars, as well as between BE and indicators of oral/dental pathology, e.g. caries, calculus, periodontoses, and antemortem tooth loss. Both types of exostoses tended to increase in frequency with age, although a significant trend was observed only for BE. We conclude that formation of exostoses is a complex process that can be invoked by any agent causing damage and inflammation of gingival tissue. However, severe occlusal stress, which is often manifested in TMJ disorder, is the main environmental factor leading to exostosis development in genetically pre-disposed individuals.     

Body mass in lowland gorillas: a quantitative analysis

Body proportions and tissue composition (e.g., relative contributions of muscle, skin, bone, and adipose to total body mass) were determined through dissection of four adult captive lowland gorillas. The relative contribution of bone varies little among the four animals (10.2-13.4%) despite considerable range in body weights (99.5-211 kg). In tissue composition, three animals have on average 37.3% muscle relative to body mass. Maximum estimates of body fat range between 19.4-44%. Differences in age, sex, and life history events partially explain the observed variation in body proportions and tissue composition among the four animals. Although gorillas are considered extremely sexually dimorphic in body weight and canine size, differences in tissue are not as dramatic as body mass differences suggest. This study found sex differences mostly in the upper body; males have relatively heavier forelimbs, including heavier deltoid, trunk-binding, and deep back muscles compared to the younger female. The old, obese female had one half the muscle tissue of the other three animals (16% vs. 37.3%), and twice the body fat (44%); forelimbs and upper body musculature were relatively well-developed to compensate for the restricted hip-joint movement due to arthritis. Data on the variation in tissue composition and body proportions in gorillas provide a basis for comparison with other hominoids, including humans. For example, compared to highly dimorphic orangutans, gorillas have more muscle, less adipose tissue, lighter forelimbs and heavier hindlimbs. Such analyses complement studies of the skeleton and contribute to our understanding of human evolution and adaptation.     

Dento-alveolar lesions and palaeodietary inferences from the Paso Alsina 1 site (eastern Pampean–Patagonian transition, Argentina)

Several archaeological researches in northeastern Patagonia and southeastern Pampas have evaluated various indicators of the diets of hunter-gatherers who inhabited these regions during the Late Holocene, including the role of plant foods. Dental analysis is an important way to introduce new information about subsistence. In this sense, the objective of this work is to document and interpret dento-alveolar lesions in an osteological sample recovered from the Paso Alsina 1 archaeological site (eastern Pampean–Patagonian transition, Argentina). This paper will explore the oral health status of individuals and discuss palaeodietary information of hunter-gatherers that inhabited the lower valley of the Colorado River during the final Late Holocene (ca. 500 years BP). The site is defined as a formal area bundle composed of 10 secondary multiple burials containing 56 individuals of both sexes and various ages (e.g., perinatal, infant, and adult). In this study, 781 teeth and 1036 alveoli from 47 maxillae and 38 mandibles were analysed from 51 adult individuals. The results indicate a moderate rate of dental wear, and dental calculus, and low percentages of caries, abscesses, and antemortem tooth loss. The information obtained suggests a diet based on a combination of proteins, fat and carbohydrates. Results are then compared with those from other lines of analysis for the study area and for the neighboring regions (northeastern Patagonia and southeastern Pampas).     

Field age determination of leopards by tooth wear

Age determination is an important tool in wildlife studies. Estimating the age of animals in the field using tooth wear criteria may be subject to error as a result of variations between individuals, habitats and populations. Data on age estimation of leopards and tooth wear characteristics are lacking. Nineteen leopards in Namibia were assessed for tooth eruption and wear. Between 1991 and 1995 leopards (including 13 individuals of known age) were monitored at one year intervals ('28 leopard years') to record age and tooth wear. At the age of two years leopards had fully developed dentition. Wear started with the incisors and canines, and spread to the premolars and molars. A chronology of tooth eruption and wear in relation to age is presented. Above the age of three years, male leopards showed higher frequencies of enamel flaking and canine fractures than females.     

Nonalimentary tooth use in the neolithic population of the Lengyel culture in central Poland (4600-4000 BC)

One hundred and four skeletons of adult individuals representing Neolithic populations of the Brze?? Kujawski group of the Lengyel Culture (Kuyavia, central Poland, 4600–4000 BC) were analyzed with regard to evidence of nonalimentary tooth use, periapical lesions and antemortem tooth loss (AMTL). Instances of nonalimentary behaviors were found in 47.1% of females and 27.5% of males. Females were primarily characterized by occlusal grooves on the incisors and canines, most probably resulting from yarn production or weaving. The most frequent defect in males was severe tooth wear extending from the incisors to first molars, caused by some hard‐to‐identify nonalimentary activities. Occlusal grooves were also found in males, but their morphology indicates processing of some coarser material. The occupational nature of the tooth defects has been confirmed by archaeological data. The only two burials with grave goods indicative of craft specialization at the sites studied contain the remains of individuals with marks of nonalimentary tooth use. Moreover, the sites provide unequivocal evidence of weaving and basketry production in the form of loom weights and imprints of cloth and mats. Periapical lesions have been found in 40.4% of males and 35.6% of females, and AMTL in 32.1% of males and 36.7% of females. Individuals with evidence of nonalimentary tooth wear are characterized both by ahigher incidence of these lesions in general, and by their more frequent location in the anterior part of the alveolar arch. Am J Phys Anthropol, 2011. © 2010 Wiley‐Liss, Inc.