High frequency of dental caries and calculus in dentitions from a British medieval town

OBJECTIVE

Dental pathology and tooth wear data can offer valuable insights into the diet and behaviour of past populations. This study aimed to investigate the presence of dietary continuity by examining different types of dental pathology and tooth wear in a medieval sample from the United Kingdom, comparing them to earlier and later samples from the same location.

DESIGN

A comprehensive examination was conducted on 41 individuals (comprising 914 permanent teeth) retrieved from the medieval cemetery of St. Owens Church in Southgate Street, Gloucester, UK. The research focused on documenting and analysing various types of dental pathology and tooth wear, such as dental caries, calculus, and tooth chipping. The frequency of these specific pathologies and wear patterns was then compared to existing literature. Additionally, non-masticatory tooth wear was also evaluated as part of the study.

RESULTS

The sample exhibits high levels of carious lesions and calculus (24 % and 74 % of teeth respectively). Anterior teeth also show an elevated chipping frequency, and along with occlusal notches on the maxillary central incisors suggest teeth were regularly used for non-masticatory purposes.

CONCLUSIONS

Caries frequency is similar to sites from later periods and may relate to the early adoption of consuming refined carbohydrates. However, remains from the same area, but the earlier Roman period, also shows high rates of caries and calculus, suggesting a continuation of consuming certain cariogenic foods, or certain behavioural/environmental factors, may instead be responsible for these pathology and wear patterns.

Metagenomics of the modern and historical human oral microbiome with phylogenetic studies on Streptococcus mutans and Streptococcus sobrinus

We have recently developed bioinformatic tools to accurately assign metagenomic sequence reads to microbial taxa: SPARSE for probabilistic, taxonomic classification of sequence reads; EToKi for assembling and polishing genomes from short-read sequences; and GrapeTree, a graphic visualizer of genetic distances between large numbers of genomes. Together, these methods support comparative analyses of genomes from ancient skeletons and modern humans. Here, we illustrate these capabilities with 784 samples from historical dental calculus, modern saliva and modern dental plaque. The analyses revealed 1591 microbial species within the oral microbiome. We anticipated that the oral complexes of Socransky et al., which were defined in 1998, would predominate among taxa whose frequencies differed by source. However, although some species discriminated between sources, we could not confirm the existence of the complexes. The results also illustrate further functionality of our pipelines with two species that are associated with dental caries, Streptococcus mutans and Streptococcus sobrinus. They were rare in historical dental calculus but common in modern plaque, and even more common in saliva. Reconstructed draft genomes of these two species from metagenomic samples in which they were abundant were combined with modern public genomes to provide a detailed overview of their core genomic diversity. This article is part of the theme issue 'Insights into health and disease from ancient biomolecules'.

Oral pathological conditions of an Early Epipaleolithic human from Southwest Asia: Ohalo II H2 as a probable case of intentional dental ablation

OBJECTIVE

To describe the oral pathological conditions of Ohalo II H2, an Early Epipaleolithic human from southwest Asia.

MATERIALS

The dentognathic skeleton of Ohalo II H2 and relevant comparative data from similar chronological and/or geographic contexts.

METHODS

Gross and x-ray observations of oral pathological conditions and occlusal wear were made following published protocols. A differential diagnosis of antemortem tooth loss is provided.

RESULTS

Ohalo 2 has two carious lesions on the right M³, pulpal exposure of left M₁, and mild to moderate anterior alveolar bone loss. The right I¹ was lost antemortem, and there is probably agenesis of the left M³.

CONCLUSIONS

The pathological conditions noted are not exceptional for a Late Upper Paleolithic forager. However, the antemortem missing right I¹ is most parsimoniously explained by intentional dental ablation.

SIGNIFICANCE

Ohalo 2 could represent the oldest example of dental ablation from the Late Pleistocene circum-Mediterranean world - predating the earliest examples from both North Africa and southwest Asia by several thousand years. The similarity of the Ohalo 2 ablation pattern with later Natufians provides further evidence of potential long-term behavioral trends related to the embodiment of social identities through international body modification within the Epipaleolithic of southwest Asia.

LIMITATIONS

The pre-Natufian (∼23,000-14,500 cal BP) human fossil record is relatively sparse, making comparisons with the Natufian (∼14,500-11,500 cal BP) phases of the Epipaleolithic difficult.

SUGGESTIONS FOR FURTHER RESEARCH

Documentation of oral pathological conditions for other pre-Natufian fossils would provide greater resolution of the temporospatial patterning of oral health and embodied social identities during the Epipaleolithic of southwest Asia.

A singular case of advanced caries sicca in a pre-Columbian skull from East Tennessee

OBJECTIVE

Documentation of an advanced case of tertiary stage treponemal disease.

MATERIALS

The well-preserved cranium and mandible of an adult male (Burial G) from the Early Woodland period (900 BCE-200 CE) Wilhoite site (40GN10) from east Tennessee.

METHODS

Macroscopic examination of the cranio-facial periostosis on Burial G for pathognomonic indicators of treponemal disease.

RESULTS

There are extensive contiguous nodular lesions on the frontal, parietals, temporals, and occipital bones. The frontal squama additionally exhibits radial scaring and circumvallate cavitating lesions. Radial scars are also present on both zygomatic bones and the endocranial surface of the calotte. There is rounding of the nasal margins in addition to periostosis on the palate.

CONCLUSIONS

Burial G unequivocally exhibits the pathognomonic reactive changes of caries sicca, radial scarring, and cavitating lesions.

SIGNIFICANCE

The Early Woodland date in combination with the advanced degree of pathognomonic reactive change is exceptional, and to date, without parallel in the pre-Columbian archaeological record of North America. Any case approaching the severity displayed here is invariably late prehistoric.

LIMITATIONS

The absence of postcrania does not permit assessment of frailty or synergism of secondary conditions.

SUGGESTIONS FOR FURTHER RESEARCH

More comprehensive documentation of pre-Columbian treponemal cases is merited.

Prevention of Dental Caries by Silver Diamine Fluoride

The use of silver diamine fluoride (SDF) for management of dental caries has gained considerable attention due to recent regulatory clearance in the United States. The primary focus of policies, presentations, and publications has been the arrest of caries lesions (cavities) because of the material's unique ability to non-invasively achieve this elusive and clinically important goal. However, SDF also has proven efficacy in prevention, ie, decreasing the incidence of new caries lesions. Analysis of nine clinical trials in children shows that SDF prevented 61% of new lesions compared to controls. To prevent one new caries lesion, clinicians need to treat four primary teeth (one patient) or 12.1 permanent molars (three patients) with SDF. The preventive effect appears to be immediate and maintains at the same fraction over time. Direct comparisons of SDF applied once per year with alternative treatments show that SDF is more effective than other topical fluorides placed two to four times per year and more cost-effective than dental sealants. Enamel lesions may be even more responsive than cavitated dentin lesions. Annual application of SDF to high-risk surfaces (eg, mesial surfaces of permanent first molars where the distal surface of the second primary molar is carious) in patients with any risk of new caries lesions appears to be the most cost-effective approach available to prevent dental caries. SDF is an underutilized evidence-based preventive agent for dental caries.

Dental markers of poverty: Biocultural deliberations on oral health of the poor in mid-nineteenth-century Ireland

OBJECTIVES

Despite subsisting on a low-cariogenic diet comprising virtually nothing more than potatoes and dairy products, poor oral health affected the quality of life for the poor of nineteenth-century Ireland. This study investigates potential biocultural reasons that may explain why this was the case.

MATERIAL AND METHODS

A total of 6,860 teeth and 9,889 alveoli from 363 permanent dentitions from the skeletal remains of impoverished adult Irish males and females who died between 1847 and 1851 in the Kilkenny Union Workhouse were examined for evidence of dental caries, periodontal disease and ante-mortem tooth loss. Caries rates were quantified and assessed by crude prevalence, frequencies, corrected caries rates and a t-health index, and evaluated by sex and age groups.

RESULTS

A higher rate of caries was present among 18-25-year-old males than females, while the opposite relationship was evident for older age groups. The prevalence rates of periodontal disease and ante-mortem tooth loss increased with age. When assessed by corrected caries rates, tooth decay is observed at a lower rate compared to contemporaneous lower to upper-class population samples from London.

DISCUSSION

Despite being low cariogenic foods, the potato starch and milk lactose of a nineteenth-century Irish laborer's diet would have lowered oral pH-values thereby increasing the risk of bacterial fermentation in dental plaque resulting in caries. Nutritional features alone cannot explain the high rates of dental caries observed in the Kilkenny workhouse population sample, however, and lifestyle factors, particularly habitual clay-pipe smoking, is considered a significant cause of poor oral health.

Earliest evidence of caries lesion in hominids reveal sugar-rich diet for a Middle Miocene dryopithecine from Europe

The formation of dental caries is mainly caused by dietary habits and therefore, may contain information for dietary reconstructions of fossil hominids. This study investigates the caries lesion in the 12.5 Ma old type specimen of Dryopithecus carinthiacus Mottl 1957 (Primates, Hominidae) from St. Stefan (Austria). Potential food sources are identified on associated palynological data, which allow conclusions about food quality, sugar availability and the hominid metabolism during the Middle Miocene. Using micro computed tomography (μCT) and scanning electron microscopy (SEM) we provide a detailed analysis and characterization of the individuals' caries type. Its lesion is compared with a dataset of 311 wild chimpanzees, indicating morphological and etiological differences in caries formation between both species. The affected molar of D. carinthiacus reveals features known from severe dental caries in humans: (1) Cavitation with steep walls and smooth surface; (2) Reparative dentine at the roof of the pulp chamber; (3) Sclerotic dentine below the cavitation; (4) Association with dental calculus and (5) Unilateral usage of the healthy right tooth row. Its advanced primary caries, initiating on the intact enamel surface, indicates a frequent intake of highly cariogenic sugar-rich fruits, which likely exceeds the frugivory of extant chimpanzees. This finding corresponds with the associated palynological record, which infers a habitat with nearly year-round supply (9-10 months/year) of high quality foods (>carbohydrates; < fibers). Our conclusions challenge the model of a step-wise increase in dietary quality during hominid evolution and support the uricase hypothesis, which discusses the hominid autapomorphy of a fructose-based fat accumulation for periods of starvation. This model receives further validation by the identification of soft-tissue preservation, interpreted as fossilized white adipose cells, in the articulated hominid skeleton of Oreopithecus bamboli from Italy.

Oral health status in historic population: Macroscopic and metagenomic evidence

Recent developments in High-Throughput DNA sequencing (HTS) technologies and ancient DNA (aDNA) research have opened access to the characterization of the microbial communities within past populations. Most studies have, however, relied on the analysis of dental calculus as one particular material type particularly prone to the molecular preservation of ancient microbial biofilms and potential of entire teeth for microbial characterization, both of healthy communities and pathogens in ancient individuals, remains overlooked. In this study, we used shotgun sequencing to characterize the bacterial composition from historical subjects showing macroscopic evidence of oral pathologies. We first carried out a macroscopic analysis aimed at identifying carious or periodontal diseases in subjects belonging to a French rural population of the 18th century AD. We next examined radiographically six subjects showing specific, characteristic dental pathologies and applied HTS shotgun sequencing to characterize the microbial communities present in and on the dental material. The presence of Streptococcus mutans and also Rothia dentocariosa, Actinomyces viscosus, Porphyromonas gingivalis, Tannerella forsythia, Pseudoramibacter alactolyticus, Olsenella uli and Parvimonas micra was confirmed through the presence of typical signatures of post-mortem DNA damage at an average depth-of-coverage ranging from 0.5 to 7X, with a minimum of 35% (from 35 to 93%) of the positions in the genome covered at least once. Each sampled tooth showed a specific bacterial signature associated with carious or periodontal pathologies. This work demonstrates that from a healthy independent tooth, without visible macroscopic pathology, we can identify a signature of specific pathogens and deduce the oral health status of an individual.

"Karius and Baktus": A Critical Appraisal of Enger's Seminal Storybook

Karius and Baktus, first published in 1949, is one of the most influential storybooks with dental caries as main theme and it remains in wide use for domestic health education. This study aimed at assessing oral health related contents of the historic storybook in the light of the current body of cariologic evidence. Two investigators independently identified phrases in the storybook with cariologically relevant content. Dental health related contents were systematically evaluated with respect to the current body of cariologic evidence. Karius and Baktus highlights important etiopathogenetic and preventive aspects such as sugars consumption and tooth brushing with toothpaste. Its behavior management techniques and narrative health didactics concerning dental care for children are, however, outmoded. The cariologic core statements in Karius and Baktus have remained valid whereas certain narrative features may have some drawbacks when employing the historic storybook for educational purposes for young children.

Did Richard III pray to Saint Apollonia for relief from toothache?

Richard III is known to have had a particular devotion to St Apollonia who is the Patron Saint of sufferers from toothache. The dentition in his skeleton exhumed from a car park in Leicester shows missing teeth which are thought to have been extracted due to caries. It is suggested that Richard, when he was Duke of Gloucester, had prayed to St Apollonia for the relief of toothache before submitting to undergo dental extractions.

Dental worm disease

During human evolution, the period in which groups of humans stopped harvesting fruits and seeds growing wild and introduced the cultivation of cereals as well as the domestication of animals represents a very important event. This circumstance had a considerable impact on human pathocenosis, increasing the risk of infectious diseases of animal origin. The aim of this review was to summarise the archaeological and palaeo-pathological evidence in the literature concerning this topic. Starting from early prehistory (about 1.5 million years ago) up to the historical period, several authors have described the changes in human habits and the consequent changes in food supply, leading to the transition from a protein- to a carbohydrate-rich diet across a broad interval of time. This led to additional problems for human health. The increased accumulation of carbohydrate debris in the odonto-stomatological apparatus, without the appropriate use of hygiene in the oral cavity, increased the risk of infectious disease involving the mouth. Therefore, since the Neolithic period there has been a higher risk of tooth caries, abscesses, deep infection of the teeth roots, reaching also the mandibular and maxillary bone. Several hypotheses have been proposed by the distinct civilizations, which have alternated in the different ages, to explain the cause of these human health problems, including the idea that a "dental worm" could be involved in this process, such as in the Sumerian period. We describe and discuss further modifications of this theory, developed in Egypt, Assyria, Babylon, China, Greece, in Etruscan cities and in Rome in ancient times as well as in the Middle Ages, and the evolution of scientific thought on this topic in the past 300 years. In addition, the results of some palaeo-pathological studies, which were performed on human remains, such as the maxillary bone and teeth, mainly in different geographical areas in Italy, are examined and reported.

[The historical materials of stomatology in the All Things, Prescriptions of Fifty-two Diseases and Yinshu]

All Things, Prescriptions of Fifty-two Diseases and Yinshu were three bamboo and silk medical manuscripts which form-time was no later than the late Warring States period. From the visible bamboo and silk, the ancient Chinese knew the relationships between some drugs and the volume of saliva and used compound drugs to treat dental caries. Some oral and maxillofacial diseases, such as inflammation and pain of oromaxillo-facial region, temporomandibular dislocation and the methods of treatment were descriped in these books. Mouth-rinsing and tooth-picking were the more often used methods for maintaining oral hygiene. Kouchi(clicking the tooth)was also used for prevention and/or treatment of caries. Most of these knowledge were the first documents in ancient China.

Dental health in antique population of Vinkovci - Cibalae in Croatia (3rd-5th century)

Roman city Cibalae (Vinkovci) - the birthplace of Roman emperors Valentinian I and Valens was a very well developed urban ares in the late antique what was evidenced by numerous archaeological findings. The aim of this paper is to get insight in dental health of antique population of Cibalae. One hundred individuals with 2041 teeth dated to 3rd - 5th century AD have been analyzed for caries, antemortem tooth loss, periapical diseases and tooth wear. Prevalence of antemortem tooth loss was 4.3% in males, 5.2% in females. Prevalence of caries per tooth was 8.4% in males, 7.0% in females. Compared to other Croatian antique sites, ancient inhabitants of Roman Cibalae had rather good dental health with low caries prevalence and no gender differences. Statistically significant difference was found between males in females in the prevalence of periapical lesions and degree of tooth wear. Periapical lesions were found only in males.

Feline Caries in Two Cats from a 13th Century Archeological Excavation

Mandibles of two cats containing carious lesions were discovered among the previously published findings of feline dental resorptive lesions from materials examined at an archaeological museum. These lesions were too small to be noted on radiographs, and consisted of two inconspicuous enamel lesions in a mandibular left first molar tooth (309), a clinically visible white spot area containing an enamel lesion in a mandibular left fourth premolar tooth (308), and a root surface caries in the 308 of a different specimen. Histologic examination using special stains and polarized light revealed both initial and early initial stage enamel caries, as well as root surface caries. Knoop hardness measurements confirmed these findings, considered the first documented cases of feline caries.

Prevalence and care index of early childhood caries in mainland China: evidence from epidemiological surveys during 1987-2013

Early childhood caries (ECC) is the most common chronic disease in young children. Its reported prevalence varies greatly across China. This systematic review aimed to explore the epidemiological characteristics of ECC in mainland China from 1987 to 2013. In total, 102 articles were included. The pooled national prevalence and care index (ft/dmft%) for ECC were 65.5% and 3.6%, respectively. The overall ECC prevalence declined from 77.9% during 1987-1994 to 56.4% during 2010-2013. The pooled ECC prevalence for children aged 1-6 years was 0.3%, 17.3%, 40.2%, 54.4%, 66.1%, and 70.7%, respectively. There was no significant difference in prevalence between boys (59.1%) and girls (58.9%); and the care index was also similar (8.1% versus 7.7%). Slightly higher ECC prevalence was observed in rural areas (63.5%) compared with urban areas (59.5%) (RR = 1.08, 95% CI: 1.02-1.14); but a much higher care index was reported in urban children (6.0%) than their rural counterparts (1.6%) (RR = 3.68, 95% CI: 2.54-5.35). The 2006-2013 map of ECC prevalence among 5-year-olds showed wide geographic variations across China. Four adjacent provinces, including Sichuan, Chongqing, Hubei, and Shaanxi, constituted the areas with the lowest ECC prevalence in mainland China.

Sex differentials in caries frequencies in Medieval London

OBJECTIVE

Tooth decay is one of the most common oral infections observed in skeletal assemblages. Sex differentials in caries frequency are commonly examined, with most studies finding that females tend to have a higher frequency of carious lesions (caries) compared to males. Less research has examined differences in caries between males and females with respect to age in past populations. Findings from living populations indicate that caries frequencies are higher in females, at least in part, because of the effects of estrogen and pregnancy. We are interested in the interaction of age, sex, and caries in medieval London, during a period of repeated famines, which might have exacerbated underlying biological causes of caries sex differentials.

DESIGN

We examined caries in adults from two medieval London cemeteries dating to c. 1120-1539 AD: St. Mary Spital (n=291) and St. Mary Graces (n=80) to test the hypothesis that males and females have different caries frequencies irrespective of age. The association between maxillary molar caries and sex was tested using hierarchical log-linear analysis to control for the effects of age on caries frequencies.

RESULTS

The results indicate a higher frequency of maxillary molar caries in females (P<0.00), and that the age distribution of caries differs between the sexes (P=0.01), with a consistent increase in frequency with age for females until late adulthood, but not males.

CONCLUSIONS

The difference in caries frequencies is not explained by differences in the age distributions of the sexes. Differences in the age patterns of caries for males and females could be the result of biological factors that present during reproductive age, differences in diet, or differential access to resources during famine.

Sugar industry influence on the scientific agenda of the National Institute of Dental Research's 1971 National Caries Program: a historical analysis of internal documents

BACKGROUND

In 1966, the National Institute of Dental Research (NIDR) began planning a targeted research program to identify interventions for widespread application to eradicate dental caries (tooth decay) within a decade. In 1971, the NIDR launched the National Caries Program (NCP). The objective of this paper is to explore the sugar industry's interaction with the NIDR to alter the research priorities of the NIDR NCP.

METHODS AND FINDINGS

We used internal cane and beet sugar industry documents from 1959 to 1971 to analyze industry actions related to setting research priorities for the NCP. The sugar industry could not deny the role of sucrose in dental caries given the scientific evidence. They therefore adopted a strategy to deflect attention to public health interventions that would reduce the harms of sugar consumption rather than restricting intake. Industry tactics included the following: funding research in collaboration with allied food industries on enzymes to break up dental plaque and a vaccine against tooth decay with questionable potential for widespread application, cultivation of relationships with the NIDR leadership, consulting of members on an NIDR expert panel, and submission of a report to the NIDR that became the foundation of the first request for proposals issued for the NCP. Seventy-eight percent of the sugar industry submission was incorporated into the NIDR's call for research applications. Research that could have been harmful to sugar industry interests was omitted from priorities identified at the launch of the NCP. Limitations are that this analysis relies on one source of sugar industry documents and that we could not interview key actors.

CONCLUSIONS

The NCP was a missed opportunity to develop a scientific understanding of how to restrict sugar consumption to prevent tooth decay. A key factor was the alignment of research agendas between the NIDR and the sugar industry. This historical example illustrates how industry protects itself from potentially damaging research, which can inform policy makers today. Industry opposition to current policy proposals-including a World Health Organization guideline on sugars proposed in 2014 and changes to the nutrition facts panel on packaged food in the US proposed in 2014 by the US Food and Drug Administration-should be carefully scrutinized to ensure that industry interests do not supersede public health goals.

[Arturo Beretta and the "trophomicrobic theory of the caries"]

The most original contribution made by the Italian School to the study of caries aetiology is undoubtedly the "trophomicrobic theory" proposed by Arturo Beretta, the first teacher of dentistry at the University of Bologna in 1918. This article brings biographical and bibliographical notes about Beretta (who was, among other things, Dean of the Faculty of Medicine of Bologna and Senator), and summarises the principles of his theory, which adds to Miller's "chemical-parasitic" theory of caries-predisposing properties of the enamel and host saliva. It also recalls the work of major Italian and non-Italian researchers who have used or modified Beretta's idea.

Forensic odontological examination of a 1500 year-old human remain in ancient Korea (Gaya)

Forensic odontological examination was performed on one of the 1500-year old human remains of ancient Korea (Gaya) excavated from a burial site at Songhyeon-dong, Changnyeong, South Korea in April, 2008. The main purpose of the examination was to age estimate the remains and record any dental characteristics to aid full-body reconstruction and life history data collection. Oral and radiographic examinations and metric data collection were conducted. During the oral examination, the following observations were made: dental caries, semi-circular abrasion on the maxillary right lateral incisor and enamel hypoplasia on the left and right canines and first premolars in the mandible. The metric data was similar to that of average metric data of modern Koreans. Age estimation was initially conducted using the degree of dental attrition with methods of Takei and Yun, and was estimated to be approximately 40 years. However, it was observed in the radiographic examination, that the maxillary right second molar, together with the mandibular left and right second and third molars had incompletely developed root apices. The age estimation was then performed using the developmental status of the lower second and third molars. The age was estimated to be approximately 16 years using Lee's method which was consistent with the estimation using forensic anthropology. This case study highlights that the degree of attrition should not be used as a sole indicator for age estimation.

[Caries of permanent dentition in medieval inhabitants of Wrocław]

INTRODUCTION

The study of dentition plays an important role in the reconstruction of the diet and in assessment of the overall health and living conditions of paleopopulations. The aim of this study was to determine the condition of permanent dentition of medieval inhabitants of Wrocław basing on the prevalence and intensity of caries in permanent dentition.

MATERIAL AND METHODS

The material consisted of 1156 permanent teeth from 118 skulls recovered from two medieval cemeteries in Wrocław: the parish cemetery at the St. Elisabeth Church (13th-14th century) and the cemetery in Ołbin (12th-13th century). Two age classes were formed taking into account anthropologic assessment and group size. The younger class consisted of material up to the age of 35 years; the remaining skulls were assigned to the older class. The prevalence and incidence of caries was determined.

RESULTS

The prevalence and intensity of caries was 56.91% and 15.7%, respectively. Carious lesions predominated in males and in the older age class.

CONCLUSIONS

The prevalence and intensity of caries in permanent dentition did not differ from other medieval populations and increased with age. High prevalence of caries reflects a high proportion of carbohydrates in the diet of medieval inhabitants of Wrocław, their high socioeconomic status, and poor oral hygiene.

Mosquitoes, flies and dental cavities: Dr. Howard Riley Raper's public campaign to prevent toothache

Dr. Howard Riley Raper (1886-1978) was an early oral health pioneer and dental roentgenology faculty member of the Indiana Dental College (IDC) who single-handedly introduced key concepts in radiology to dentistry. Due to his efforts, IDC became in 1910-11 the first dental school to have a regular course in dental radiology. Virtually all American dental schools soon added this subject to their regular curriculum. Raper's text, Elementary and Dental Radiography (1913) became the first comprehensive student textbook of dental X-ray diagnosis. In his 1933 Blue Book entitled, The New Aim in the Care of the Teeth, Raper elaborated upon his mission to prevent caries, by comparing the insidious damages of tooth decay with the threat of insect-borne disease.

Can dental caries be interpreted as evidence of farming? The Asian experience

The seminal development of control of food production and its social and biological effects on human populations has for a long time been one of the foci of prehistoric research. The relationship between diet and oral pathology is well recognised and accepted to the point where rates of dental caries in particular have been seen as indicative of subsistence mode. This is despite the complex aetiology of caries, with both genetic and environmental factors other than diet contributing to lesion frequency. Most publications considering prehistoric diet and caries acknowledge the contribution of non-dietary variables but provide a more comfortable dietary explanation, with the role of domesticated starchy staples paramount. This widespread acceptance of a simple relationship between dental pathology and starchy carbohydrates needs to be challenged, as there is no reason why one dietary component would be solely responsible for the development of caries or why all carbohydrates should have the same effect. Some years ago, on the basis of evidence from prehistoric rice farming communities in Southeast Asia, we questioned the relationship between dental caries and the presumptive increased carbohydrate consumption consequent to the adoption of agriculture. This paper reviews recent literature on the topic and presents evidence that there is still no simple or universally applicable explanation for patterns of changes in caries frequencies during human prehistory.

Scientific knowledge and clinical authority in dentistry: James Sim Wallace and dental caries

Once the germ theory had become generally accepted within medicine, the importance of experimental science to the improvement of medical practice could no longer be reasonably doubted. However, clinicians still sought to retain control of how knowledge that had originated in the laboratory was interpreted and applied within practical diagnostics and therapeutics. Thus how practitioners incorporated new scientific knowledge into their medical discourse and practice is a matter for careful empirical inquiry. James Sim Wallace, born in Renfrewshire in 1869 and a graduate in medicine from the University of Glasgow, was a leading figure in British dentistry throughout the first half of the twentieth century. Through an examination of his voluminous writings, we explore how the new 'chemico-parasitical' theory of dental caries was accommodated within dentists' understanding of oral hygiene. The paper also looks at the controversies that surrounded the application of the vitamin theory to the problems of rickets and dental caries, focusing on the contentious interaction between Sim Wallace and his colleagues, on the one hand, and the eminent physiologists May and Edward Mellanby, on the other.

[Dental care, dental diseases and dentistry in antiquity]

Numerous written relicts, belletristic works (poems of Martial, Juvenal, Ovid etc.) indicate that oral hygiene and its tools (toothbrush, toothpick, use of tooth pastes and tooth-powder) were used long before our times. Already ancient people started to remove, file, dye and inlay teeth. The teeth were dyed red, green or black in Egypt, red or brown (with henna or betel) in India, white by Romans. The teeth decoration has a long but forgotten history. The most skillful and artistic work was done by the Maya's between 900 BC and 1500 AD. The modification of contours (more than fifty forms) of the incisors were practiced also in Mesoamerica. Dentistry was surely practiced in ancient Egypt, India, China, Greece and Rome, while odontology and especially suitable dental appliances arose only by Etruscan. Dental prosthesis, including bridges and simple retention bands were invented by the Etruscans 2500 years ago. These Etruscan bridges were worn mostly by females, suggesting that cosmetics was the principal dental concern. Some,--if not all--of the Roman and other prostheses have been purely ornamental. Orthodontic appliances are also Etruscan invention. The holes caused by caries were filled with garlic, incense, caraway seed in Egypt, with wood or lead in Rome, and with "silver-paste" (amalgam) in ancient China. The toothache was cured with poppy-tee, or hashish and nightshade plants (Solanaceae) in Egypt, Greece, Roman Empire while with coca (Erythroxylon coca) in South-America.

[The developmental history of the dental filling materials]

Caries may cause substantial defects in the hard tissue of teeth. The dental filling for defects is an effective method to resume teeth complete form and masticatory function as well as aesthetic effects. The filling material is artificial restorative material to fill the dental defects. Tracing back the developing process of dental filling materials, we can see the advancement of stomotology of human beings. There was a revolutionary change in the filling materials from filling dental cavity with Chinese medicinal herbs to silver paste, from establishing the composition and proportion standardization of the silver amalgam filling materials to the application of new macromolecule compound resin. This is a continuous improvement and renewal in the idea and technology of dental filling treatment so that perfects the dental filling method and enables the retention of more healthy dental tissue. In addition, it pushes the development of dental aesthetics, adhesives and technology. With the improvement of people's health standard, aesthetic demands and environmental awareness, compound resin restorative materials has become clinically preferred dental filling materials of doctors and patients in clinic.

Oral and physiological paleohealth in cold adapted peoples: Northeast Asia, Hokkaido

This paper examines variables useful in reconstructing oral (caries, antemortem tooth loss, alveolar defects) and physiological (cribra orbitalia, linear enamel hypoplasia) well-being in two bioarchaeological assemblages from Hokkaido, Japan: Okhotsk (n = 37 individuals) and Jomon (n = 60). Findings are compared and contrasted with each other, with published series from Honshu Japan, and samples from climatically near-equivalent Alaska. It was found that more meaningful comparisons of Hokkaido paleohealth could be made with Alaskan material, rather than the more southerly Jomon. Results were ambiguous with respect to physiological well-being. Low levels of LEH in the cold-adapted samples suggest operating in arctic and subarctic environments with marine-based subsistence regimes is not physiologically expensive. However, the relatively high levels of cribra orbitalia in Hokkaido, relative to Alaska, suggest the picture is not straightforward: the reasons for elevated cribra orbitalia in Hokkaido are unclear. The subarctic and arctic samples formed three broadly similar groupings in terms of oral health profiles: (1) Aleuts and Eskimo; (2) Ipiutak and Tigara; (3) Hokkaido Jomon, Okhotsk, and Kodiak Island. Differences between these groupings could be explained with a combination of sample demographics and subsistence orientations. The extremely high frequency of caries in one sample, caribou hunting Ipiutak, may have been influenced by factors such as low levels of dietary magnesium and potentially cariogenic foodstuffs, such as preparations of caribou stomach contents. It was concluded that oral health profiles are potentially sensitive to differences in subsistence strategies among cold-adapted hunter-gatherers, although they lack predictive value.

Caries and periodontal disease: insights from two U.S. populations living a century apart

PURPOSE

To compare caries experience and periodontal status between two U.S. populations that lived a century apart.

MATERIALS AND METHODS

The University of Pittsburgh, School of Dental Medicine possesses a collection of skulls that was organised in the first half of the 20th century. Those individuals are likely to have lived in the northeast United States during the late 19th century and the early 20th century. The present study measured caries and periodontal disease morbidity in the collection of skulls and compared the data with current prevalence rates of these diseases in the United States (from the third National Health and Nutrition Examination Survey 1988-94).

RESULTS

Periodontal health appears to have improved since this population resided, over 150 years ago. On the other hand, Americans between the ages of 16 and 39 appear to have the same prevalence of caries as a group of individuals that lived 150 years ago.

CONCLUSIONS

The periodontal health of Americans has probably improved in the last 100 years. The individuals identified that were free of caries and periodontal disease among the group that lived during the 19th century may have some protective factor against these diseases.

Prevalence of dental caries and tooth wear in a Byzantine population (13th c. a.d.) from northwest Turkey

Dental caries and wear are important conditions to record in archaeological collections. Reconstruction of the life of ancient peoples can be accomplished by studying their dental remains. The aim of the present paper was to determine the frequency, distribution, and characteristics of dental caries, dental wear and related diet in the mediaeval Byzantine population of Iznik in northwest Turkey. The analysed sample consisted of the dental remains of 56 individuals with the total of 280 teeth. The majority (261 or 93.2%) of the teeth belonged to the permanent dentition. The frequency of antemortem tooth loss in the sample was 6.5% and the frequency of caries was 6.8%. The most frequent recorded caries were mesial (3.3%), followed by buccal (3%). The frequency of dental wear was rather high (84.2%) exhibiting presence of dentin clusters mostly. This finding is consistent with the hypothesis of caries attrition competition based on the assumption that a beneficial effect of tooth wear is to avoid development of caries. High wear in the archaeological population can be linked to the fact that the cumulative effects of attrition as a result of the Byzantine diet.

Caries prevention through the fluoridation of milk. A review

The aim of this review is to give an overview of 50 years experience of milk fluoridation and draw conclusions about the applicability of the method. Fluoridated milk was first investigated in the early 1950s, almost simultaneously in Switzerland, the USA and Japan. Stimulated by the favourable results obtained from these early studies, the establishment of The Borrow Dental Milk Foundation (subsequently The Borrow Foundation) in England gave an excellent opportunity for further research, both clinical and non-clinical, and a productive collaboration with the World Health Organization from the early 1980s onwards. Numerous peer-reviewed publications in international journals showed clearly the bioavailability of fluoride in milk, and increased concentrations of fluoride in saliva, dental plaque, dental enamel and dentine, and urine, after consumption of fluoridated milk. Clinical trials were initiated in the 1980s--some of these can be classed as randomised controlled trials, while most of the clinical studies were community preventive programs. These evaluations showed clearly that the optimal daily intake of fluoride in milk is effective in preventing dental caries. At present, milk fluoridation programs are running continuously in about ten countries of the world. Fluoridation of milk can be recommended as a caries preventive measure where the fluoride concentration in drinking water is suboptimal, caries experience in children is significant, and there is an existing school milk program. The program should aim to provide fluoridated milk for at least 200 days per year and should commence before the children are 4 years of age.

Dietary variation and stress among prehistoric Jomon foragers from Japan

Current archaeological evidence indicates that greater dietary reliance on marine resources is recorded among the eastern Jomon, while plant dependence prevailed in western/inland Japan. The hypothesis that the dietary choices of the western/inland Jomon will be associated with greater systemic stress is tested by comparing carious tooth and enamel hypoplasia frequencies between the eastern and western/inland Jomon. Demographic collapse coincides with climate change during the Middle to Late Jomon period, suggesting dwindling resource availability. It is hypothesized that this change was associated with greater systemic stress and/or dietary change among the Middle to Late Jomon. This hypothesis is tested by comparing enamel hypoplasia and carious tooth frequencies between Middle to Late and Late to Final Jomon foragers. Enamel hypoplasia was significantly more prevalent among the western/inland Jomon. Such findings are consistent with archaeological studies that argue for greater plant consumption and stresses associated with seasonal resource depletion among the western/inland Jomon. Approximately equivalent enamel hypoplasia frequencies between Middle to Late and Late to Final Jomon foragers argues against a demographic collapse in association with diminished nutritional returns. Significant differences in carious tooth frequencies are, however, observed between Middle to Late and Late to Final Jomon foragers. These results suggest a subsistence shift during the Middle to Late Jomon period, perhaps in response to a changed climate. The overall patterns of stress documented by this study indicate wide-spread environmentally directed biological variation among the prehistoric Jomon.