Dental caries among the prehispanic population from Gran Canaria

Oral conditions of the pre-Hispanic mummies of Gran Canaria (Canary Islands, Spain)

OBJECTIVE

To analyse the oral conditions of pre-Hispanic mummies from Gran Canaria (5th-11th centuries AD), comparing the results with published data from the non-mummified population.

MATERIALS

440 teeth and 764 alveoli of 30 adult mummies.

METHODS

Macroscopic examination of pathological and non-pathological features of the oral cavity, using standardized criteria.

RESULTS

The mummies reveal frequent dental caries (11.8%), especially affecting molars (27.6%), a high prevalence of calculus (66.3%) and periodontal disease (34.9%). The average wear is characterized by extensive dentine exposure. Periapical lesions (10.6%) and antemortem tooth loss (AMTL) (15.9%) are common. A high percentage of individuals exhibit linear enamel hypoplasia (LEH) (84%). Except for periodontitis, the data indicate the absence of significant statistical differences between the mummies and the skeletonized sample.

CONCLUSIONS

The profile of the dental pathologies of the mummies indicates a carbohydrate-rich diet that contained abrasive grit from the stone querns used to grind cereals. Comparison of the oral conditions of mummified and skeletonized remains shows no differences in access to food resources, reinforcing the recent rejection of the traditional interpretation of the mummies as the pre-eminent status group of Canarian society.

SIGNIFICANCE

This is the first study to delve into the oral conditions of pre-Hispanic mummified remains from Gran Canaria. The results have implications for the framing of research questions based on the social status of these mummies.

LIMITATION

The preserved sample of mummified remains of ancient Canarians is small.

SUGGESTION FOR FURTHER RESEARCH

Comparative analysis from a diachronic perspective would improve understanding of the historical development of ancient Canarians.

The frequency and distribution of caries among the Iron Age population (about 2200 years BP) buried in the Mausoleum of Emperor Qinshihuang

OBJECTIVES

The purpose of this study was to assess the prevalence, distribution, and intensity of dental caries in the Iron Age population of northern China in order to increase knowledge about the type of food, dietary habit, and social stratification in this Iron Age people.

MATERIALS AND METHODS

The samples analyzed were dental remains of 1548 permanent teeth from 69 male individuals unearthed from the Qin archaeological site of Emperor Qinshihuang's Mausoleum in Lintong (northern China). The sex and the age-at-death of the samples were estimated.

RESULTS

Overall frequency of antemortem tooth loss in the samples was 0.8%. The proportion of individuals with at least one carious tooth was 65.2%, and the frequency of carious lesions was 9.4%, both showing a trend to rise as age increased. Data obtained on dental caries and antemortem tooth loss provided a corrected rate of 9.5% of teeth with caries. The most frequent carious lesions were occlusal lesions (2.6%), followed by interproximal (2.5%) and buccal/lingual lesions (1.0%). Tooth type analysis showed that molars had the highest percentage of caries (18.6%), followed by premolars (4.5%), canines (3.0%), and incisors (3.0%). The total SRCI was 1.6, increasing with age.

CONCLUSIONS

These findings indicate that dental caries may be related, at least in part, to the subsistence and diet of this Iron Age population.

Socio-cultural factors in dental diseases in the Medieval and early Modern Age of northern Spain

The aim of this study is to present, discuss and compare the results of pathological conditions in teeth from skeletal remains found in the northern part of the Iberian Peninsula (Spain) in four Medieval cemeteries (late 15th century) and three cemeteries from the Modern Age (late 18th century). The final objective was to evaluate the impact of socioeconomic and cultural changes that took place during the early Modern Age in Spain, on oral health. Dental caries and antemortem tooth loss were considered as indicators of dental disease. A significant increase of both dental caries and antemortem tooth loss occurred in Modern Age individuals when compared to Medieval values, as reported for other regions. Increased trade with other continents may explain this deterioration of dental health, as food exchanges (mainly with America) contributed to diet changes for the overall population, including higher carbohydrate consumption (introduction of potatoes) at the expense of other vegetables. A sex-specific increase of dental disease with age, and a significantly higher prevalence of carious lesions in Modern Age females than in males, were also found. These changes can be explained by women having had limited access to dental care after the Middle-Modern Age transition, as a consequence of socio-cultural and political changes. In these changes, an increasing influence of the Catholic Church in Spanish society has to be noted, as it can contribute to the explanation of the unequal dental health of men and women. Women were socially excluded from dental care by regulations inspired by religious precepts.

The maternal aborigine colonization of La Palma (Canary Islands)

Teeth from 38 aboriginal remains of La Palma (Canary Islands) were analyzed for external and endogenous mitochondrial DNA control region sequences and for diagnostic coding positions. Informative sequences were obtained from 30 individuals (78.9%). The majority of lineages (93%) were from West Eurasian origin, being the rest (7%) from sub-Saharan African ascription. The bulk of the aboriginal haplotypes had exact matches in North Africa (70%). However, the indigenous Canarian sub-type U6b1, also detected in La Palma, has not yet been found in North Africa, the cradle of the U6 expansion. The most abundant H1 clade in La Palma, defined by transition 16260, is also very rare in North Africa. This means that the exact region from which the ancestors of the Canarian aborigines came has not yet been sampled or that they have been replaced by later human migrations. The high gene diversity found in La Palma (95.2+/-2.3), which is one of the farthest islands from the African continent, is of the same level than the previously found in the central island of Tenerife (92.4+/-2.8). This is against the supposition that the islands were colonized from the continent by island hopping and posterior isolation. On the other hand, the great similarity found between the aboriginal populations of La Palma and Tenerife is against the idea of an island-by-island independent maritime colonization without secondary contacts. Our data better fit to an island model with frequent migrations between islands.

Role of wild plant foods among late Holocene hunter-gatherers from Central and North Patagonia (South America): An approach from dental evidence

This study evaluates the role of plant foods in the subsistence of hunter-gatherers that inhabited the Central East, Northwest, and Northeast Patagonia (Argentina) during the late Holocene (ca. 3,000-500 years BP). The goal of the present study is to assess the temporal variation of dental caries ratio and wear rate in skeletal samples to ascertain if the biological information supports the dietary shift toward greater consumption of wild plant foods around 1,500 years BP, suggested by other types of evidence. The authors registered caries, antemortem and postmortem tooth loss, and tooth wear from eight samples belonging to hunter-gatherers from Patagonia for which chronological sequences from early late Holocene (ca. 3,000-1,500 years BP) up to final late Holocene (ca. 1,500-500 years BP) are available. The results indicate that caries percentages in Patagonian samples fall within the range established for hunter-gatherers but there are significant geographical differences. In addition, caries ratio does not change significantly through time, so the amount of carbohydrates consumed seems to have remained fairly constant since 3,000 years BP. In contrast, there is a marked temporal trend toward the reduction of wear rates in the three areas, suggesting a faster rate in early late Holocene than in final late Holocene. These results would reflect a change to less hard and/or abrasive diets in the final late Holocene, probably owing to differences in food processing methods employed.

Explaining sex differences in dental caries prevalence: Saliva, hormones, and “life-history” etiologies

When dental caries rates are reported by sex, females are typically found to exhibit higher prevalence rates than males. This finding is generally true for diverse cultures with different subsistence systems and for a wide range of chronological periods. Exceptions exist, but are not common. In this paper, we present new data for sex differences in dental caries rates among the Guanches (Tenerife, Canary Islands), summarize results of meta-analyses of dental caries prevalence, and emphasize new research that stresses the critical role of female hormones and life-history events in the etiology of dental caries. Among the Guanches, corrected tooth-count caries rates for females (8.8%, 158/1,790) are approximately twice the frequency of caries among males (4.5%, 68/1,498). Higher caries prevalence among females is often explained by one of three factors: 1) earlier eruption of teeth in girls, hence longer exposure of girls' teeth to the cariogenic oral environment, 2) easier access to food supplies by women and frequent snacking during food preparation, and 3) pregnancy. Anthropologists tend to favor explanations involving behavior, including sexual division of labor and women's domestic role in food production. By contrast, the causal pathways through which pregnancy contributes to poorer oral health and higher caries rates are deemphasized or discounted. This paper presents recent research on physiological changes associated with fluctuating hormone levels during individual life histories, and the impact these changes have on the oral health of women. The biochemical composition of saliva and overall saliva flow rate are modified in several important ways by hormonal fluctuations during events such as puberty, menstruation, and pregnancy, making the oral environment significantly more cariogenic for women than for men. These results suggest that hormonal fluctuations can have a dramatic effect on the oral health of women, and constitute an important causal factor in explaining sex differences in caries rates.