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Pathology

Claire Nightingale and Jonathan Sandy

in Illustrated Questions in Orthodontics

Monks and Kings Intervene: The Kandy Perahara in Central Śrī Lanka

Paul Younger

in Playing Host to Deity: Festival Religion in the South Indian Tradition

The festival in Kandy in the highlands of central Sri Lanka is unusual because in the eighteenth century, an older festival tradition was transformed by an order of the emperor Krti or Rajasimha to ... More

The festival in Kandy in the highlands of central Sri Lanka is unusual because in the eighteenth century, an older festival tradition was transformed by an order of the emperor Krti or Rajasimha to conclude the festival with a procession from the Buddhist Tooth temple. Both an archaic festival segment and a medieval agricultural segment, introduced when the Cola dynasty conquered Sri Lanka, were clear in the description of the festival given by Robert Knox who was held prisoner in Kandy in the seventeenth century. The more Buddhist‐oriented festival described in the Buddhist Chronicle of the eighteenth century had a very political form with each province of the empire expected to bring its drummers, dancers, elephants, and political officials to march in the procession. Today those elements of the procession remain the same, but they are now thought of as a reflection of medieval grandeur.Less

 The Enshrining of the Relics

Stephen C. Berkwitz

in The History of the Buddha's Relic Shrine: A Translation of the Sinhala Thūpavaṃsa

This chapter presents an English translation of the Sinhala Thūpavaṃsa, focusing on the seven relics that were not scattered into smaller pieces: the four Tooth Relics, the two Collar Bone Relics, ... More

This chapter presents an English translation of the Sinhala Thūpavaṃsa, focusing on the seven relics that were not scattered into smaller pieces: the four Tooth Relics, the two Collar Bone Relics, and the Forehead Bone Relic. They substantiate analogous traditions wherein the Buddha's tooth, right collar bone, and forehead bone are said to have been enshrined in Laṅkā.Less

STRUCTURE REFINEMENTS

Sander Van Smaalen

in Incommensurate Crystallography

This chapter provides a complete account of the method of structure refinement of incommensurately modulated structures and incommensurate composite crystals. Modulation functions for displacive ... More

This chapter provides a complete account of the method of structure refinement of incommensurately modulated structures and incommensurate composite crystals. Modulation functions for displacive modulation, for occupational modulation, and for modulation of anisotropic displacement parameters (ADPs; temperature parameters) are described by truncated Fourier series, thus providing the Fourier amplitudes as parameters of the structure model. Constraints and restraints on the structural parameters are discussed, including the use of rigid bodies and non-crystallographic site symmetries. The block-wave (crenel) function and the saw-tooth function are presented as special modulation functions that may be alternatives to Fourier series. Next to structure refinements against single-crystal diffraction data, refinements of incommensurate structures against powder diffraction data (Rietveld refinement) are presented.Less

Does the Joker Have Six-Inch Teeth?

Roy T. Cook

in The Joker: A Serious Study of the Clown Prince of Crime

Cook’s simple question belies a deep and careful exploration – and ultimately a refutation – of the “panel transparency thesis”: the premise that “characters, objects, events, and locations within ... More

Cook’s simple question belies a deep and careful exploration – and ultimately a refutation – of the “panel transparency thesis”: the premise that “characters, objects, events, and locations within the fictional world described by a comic appear, to characters within that fiction, as they are depicted within the panels of that comic.” By way of Kendall Watson’s explorations of “fictional truth,” Cook examines the Joker’s various physiognomies in print, suggesting that, “although the Joker cannot both have and not have six-inch teeth, there is nothing contradictory about imagining that he appears to us one way during one story and that he appears to us another way during another story.” Suggesting that, given the Joker’s “multiple choice” approach to outlining his origin story, we might best understand the rendering of the character to be always already a metaphorical act, Cook concludes counter-intuitively that “we in fact know almost nothing about the Joker’s appearance.”Less

Removable appliances

Claire Nightingale and Jonathan Sandy

in Illustrated Questions in Orthodontics

Fixed appliances

Claire Nightingale and Jonathan Sandy

in Illustrated Questions in Orthodontics

Anchorage

Claire Nightingale and Jonathan Sandy

in Illustrated Questions in Orthodontics

Hair-Trigger Mouse Traps with Teeth

Carolyn M. King and Roger A. Powell

in The Natural History of Weasels and Stoats: Ecology, Behavior, and Management

This chapter introduces readers to the most important features of the weasels: their long, thin body, short legs, and short fur — the consequences of their specialized lifestyle as hunters of small ... More

This chapter introduces readers to the most important features of the weasels: their long, thin body, short legs, and short fur — the consequences of their specialized lifestyle as hunters of small mammals in tight spaces. All aspects of their lives and behaviour are subservient to their need to be small enough to follow mice and voles into their nests, and yet still strong enough to make successful kills there. As such, their skulls are elongated, their ears flat to the head, and their necks long enough to let them carry a dead vole without tripping over it. They can out-compete larger predators in exploiting small rodents, but usually come off worst in any confrontation. They are disproportionately strong for their size, but the long, thin weasel body-shape makes high demands on their metabolism. Thick fur would prevent access to rodent tunnels, so they are vulnerable to energy loss in cool climates.Less

Biological tissue

G. A. D. Briggs and O. V. Kolosov

in Acoustic Microscopy: Second Edition

Biological tissue: The elastic properties of biological tissue show much greater contrast than their optical properties. Cells can be imaged in an aqueous medium, so that the ... More

Biological tissue: The elastic properties of biological tissue show much greater contrast than their optical properties. Cells can be imaged in an aqueous medium, so that the variation with environment and time of their mechanical properties and adhesion to a substrate can be measured. For soft tissue, time‐resolved techniques are more relevant than Rayleigh wave interference. Mineralized tissues such as teeth can support Rayleigh waves, giving contrast from carious lesions and allowing line‐focus‐beam V(z) analysis to measure elastic anisotropy. Bone is an intermediate case, with contrast from its mechanical structure.Less

Oral Health

Stephanie Zaza, Peter A. Briss, and Kate W. Harris

in The Guide to Community Preventive Services: What works to promote health?

This chapter summarizes the conclusions and recommendations from the Task Force on interventions to prevent or control dental caries (tooth decay), oral (mouth) and pharyngeal (throat) cancers, and ... More

This chapter summarizes the conclusions and recommendations from the Task Force on interventions to prevent or control dental caries (tooth decay), oral (mouth) and pharyngeal (throat) cancers, and sports-related craniofacial injuries. The Task Force recommends both community water fluoridation (CWF) and school-base or school-linked pit and fissure sealant delivery programs to help reduce dental caries.Less

Changing the Face of America: Water Fluoridation and Oral Health

Brian A. Burt and Scott L. Tomar

in Silent Victories: The History and Practice of Public Health in Twentieth Century America

During the early- to mid-1900s, dental caries (i.e., tooth decay), frequently associated with uncomfortable treatment and tooth loss, was one of life's less pleasant certainties. However, the dental ... More

During the early- to mid-1900s, dental caries (i.e., tooth decay), frequently associated with uncomfortable treatment and tooth loss, was one of life's less pleasant certainties. However, the dental health outlook for Americans growing up during the later part of the 1900s was quite different. Substantial improvements in oral health were the result of many factors, including rising standards of living, better treatment technology, and more positive attitudes toward oral health. However, the widescale exposure of Americans to fluoride also played a crucial role. The concept of water fluoridation as tool for oral health began with studies which revealed that routine exposure to fluoride reduced the incidence and severity of dental caries. By the start of the 21st century, more than half of the U.S. population had access to fluoridated water. This chapter traces the historical development of fluoride as a tool for preventing dental caries.Less

Long-term management of direct restorations

Avijit Banerjee and Timothy F. Watson

in Pickard's Guide to Minimally Invasive Operative Dentistry

As has been emphasized throughout this book, minimum intervention oral/dental care involves more than just the minimally invasive operative treatment of the ... More

As has been emphasized throughout this book, minimum intervention oral/dental care involves more than just the minimally invasive operative treatment of the consequences of dental disease. It involves identifying and predicting disease patterns, and concerns the control/ prevention of disease by modifying aetiological factors and reassessing the adherence to changes in patient behaviours, attitudes, and responsibility. Monitoring the oral cavity and restored dentition ensures that the treatment undertaken, and subsequently improved oral health, is maintained. This should be accomplished through individualized strategic recall regimes. Restorations need to be reviewed regularly and occasionally refurbished, resealed, repaired, or replaced (see Figures 9.1, 9.2, and 9.3, and Section 9.5). Therefore periodic recall appointments, once an episode of treatment has been completed, are just as important as the treatment itself. It is critical that the patient understands the importance of these recall consultations as part of the ongoing care that is being offered to help to maintain their oral health. Three aspects of dental care need to be assessed at recall visits:… • the overall state of the patient’s oral and dental health (review) • the individual patient’s longer-term response/adherence to previous preventive advice and/or treatment, in moderating any aetiological factors that could cause future dental disease (reassessment) • the status and quality of the restorations present (monitoring and maintenance)…. The potential causes of restoration failure have been identified and outlined in Table 9.1. It is important to appreciate that the causes of restoration and tooth failure (see Table 9.2) are often multifactorial in nature. Indeed, as the causes of both tooth and restoration failure are inextricably linked, it is wise to consider them together, as a tooth–restoration complex. The multifactorial aetiology of restoration failure is often due to manifestations of inherent long-term weaknesses in the mechanical properties of different restorative materials (e.g. poor edge strength, wear, compressive strength, water absorption, etc.) and/or problems with the technical application of the restorative material for the chosen clinical situation (i.e. incorrect choice of material and poor placement technique). The chemistry and physical properties of the different direct, plastic restorative dental materials at a dentist’s disposal have been discussed in Chapter 7. Less

Anomalies of tooth formation and eruption

S. Parekh and K. Harley

in Paediatric Dentistry

Both the primary and permanent dentitions may be affected by variations in the number, size, and form of the teeth, as well as the structure of the dental hard ... More

Both the primary and permanent dentitions may be affected by variations in the number, size, and form of the teeth, as well as the structure of the dental hard tissues. These variations may be exclusively genetically determined, brought about by either local or systemically acting environmental factors, or possibly a combination of both genetic and environmental factors acting together. The same interplay of influences may affect the eruption and exfoliation of primary teeth, as well as the eruption of permanent teeth. This chapter considers a range of conditions involving abnormalities of the number, size, form, and structure of teeth and their eruption. It is important to be aware of the psychosocial aspect when meeting children and families affected by these conditions. We have too often heard stories of social isolation of even very young children as a result of their missing or discoloured teeth. In the case of discoloured teeth, parents and children have told us that they have been told off or teased for not looking after their teeth when the discolouration was intrinsic and unavoidable. Society’s preoccupation with ‘the perfect smile’ seems to increase; hence children denied access to aesthetic dental treatment may be genuinely disadvantaged. Wherever possible, we try to avoid the use of the word ‘normal’ in our clinical care, although the word will be used in this text. The vast majority of children with these conditions want to become ‘one of the crowd’. Thus we would speak, when offering restorative treatment for example, of making a smile ‘ordinary’ or ‘boring’. While investigating inherited conditions, it is important to make enquiries of both sides of the family tree equally. Not only does this ensure that the investigation is complete, but also it may help to alleviate any sense of ‘guilt’ felt by an affected parent. We have been questioned repeatedly about the possibility of genetic treatment for some of these inherited conditions. We are not aware of any progress in this direction at present. Hypodontia is the term most often applied to a situation where a patient has up to six missing teeth (excluding third permanent molars) as a result of their failure to develop. Less

Detection, diagnosis, and recording in the clinic

Edwina Kidd and Ole Fejerskov

in Essentials of Dental Caries

In Chapter 1 it was stressed that while all dental biofilms exhibit intense metabolic activity, only biofilms where a shift in metabolic activity towards an enhanced ... More

In Chapter 1 it was stressed that while all dental biofilms exhibit intense metabolic activity, only biofilms where a shift in metabolic activity towards an enhanced acid production over longer periods of time, will result in a net loss of mineral from the underlying tooth surface. The reflection or symptom of this is what can be detected with the naked eye and classified as the caries lesion on the tooth surface. It was pointed out that lesions may be active (if nothing changes in the oral environment, they will progress) or arrested (if nothing changes they will stay as they are). Thus, the things it is necessary to know in order to make an appropriate treatment decision are: ◆ Is a lesion present? This is detection of the lesion. ◆ Is the lesion judged to be active or arrested? This decision, adding the aspect of activity to detection, is diagnosis. ◆ Is the surface of the lesion intact or is a cavity present? If there is a cavity, can the lesion be cleaned by the patient? Diagnosis has been called a ‘mental resting place on the way to a treatment decision’. For instance, grading a lesion as active implies that the clinician considers that, if nothing is done, the demineralization will progress. Figure 3.1 is a decision tree showing how the diagnostic decision may guide the treatment. Thus, the diagnosis detects and excludes disease, assesses prognosis (considering the entire oral condition of the mouth), and forms the basis for the treatment decision. Lesions where the tooth surface is intact can be managed by the patient’s caries control measures. However, a cavity in a tooth may prevent access for the toothbrush. In addition, it may be unsightly and the tooth may be sensitive. These lesions may require restorations as a part of caries control. It is the duty of the professional to discuss with the patient whether any action is required in order to control lesion progression. Finally, the diagnosis should allow the clinical course of the disease to be monitored at subsequent visits. Less

When should a dentist restore a cavity?

Edwina Kidd and Ole Fejerskov

in Essentials of Dental Caries

At the start of this book it was commented that some dentists see restorative dentistry (fillings) as the treatment of dental caries. These dentists see prevention of ... More

At the start of this book it was commented that some dentists see restorative dentistry (fillings) as the treatment of dental caries. These dentists see prevention of caries as a separate issue. The authors profoundly disagree with this. The previous chapters have shown how dental caries develops and what it is, so in this chapter it is important to ask the question ‘with this knowledge in mind, what is the role of restorations (restorative dentistry) in caries control?’ Are restorations required or can the problem be solved by sealing all surfaces in the oral cavity—or at least those parts where surface irregularities (occlusal fissures, grooves, pits, etc.) may favour biofilm stagnation? Therefore, this chapter starts with a discussion of so-called fissure sealants. On occlusal surfaces, caries lesions may form at the entrance to the fissure because this complex morphology may be difficult to clean, particularly in the erupting tooth that is below the level of the arch and tends to be missed as the toothbrush swings by. Fissure sealants cover the fissures with a flowable resin or highly viscous glass ionomer cement, so that they are easier to clean. Their effectiveness has been proved in many studies. When first introduced in developed nations, all molar surfaces were recommended for sealing to avoid caries development and the need for fillings. This ‘sealing all teeth’ policy would now be totally incorrect for two reasons: ◆ Caries can be controlled by cleaning alone. ◆ Many of these surfaces will never develop lesions, and this automatic sealing approach is over treatment and not cost-effective. The indications for fissure sealing are: ◆ Active fissure caries has been diagnosed, but attempts at caries control have not arrested lesion progression. ◆ Occlusal surfaces are often highly irregular, and filled with grooves and fissures, and the patient or parent either cannot, or will not, remove plaque effectively. This is particularly important in the erupting molar. This surface is particularly at risk of lesion development and progression because permanent teeth can take 6–12 months to erupt; indeed, third molars may take several years. Less

Out of Regard to Custom: Tooth Modification in the Ancient and Modern Worlds

George R. Milner

in A World View of Bioculturally Modified Teeth

This overview of the volume’s chapters focuses on intentional modifications of teeth, specifically alterations of crown shape or removal, as known from historical and ethnographic sources, ... More

This overview of the volume’s chapters focuses on intentional modifications of teeth, specifically alterations of crown shape or removal, as known from historical and ethnographic sources, archaeological studies, and observations of contemporary peoples. Anterior teeth, a highly visible aspect of a person’s appearance, were altered for different reasons by past and present peoples. While purposeful modifications of the dentition are of principal interest, they must be distinguished from features that can mimic them, including use wear, pathological features, and decay or trauma-related tooth loss.Less

Bones, Teeth, and History

Alessandra Sperduti, Luca Bondioli, Oliver E. Craig, Tracy Prowse, and Peter Garnsey

in The Science of Roman History: Biology, Climate, and the Future of the Past

This chapter discusses human bones and teeth, which are the primary databank for biological anthropologists. The topic has aroused little interest among historians of antiquity. The beginnings of an ... More

This chapter discusses human bones and teeth, which are the primary databank for biological anthropologists. The topic has aroused little interest among historians of antiquity. The beginnings of an explanation of this disparity are to be sought in the fact that human skeletal remains have no obvious relevance as a source of information for politics, political institutions, political thought, government, law, religion, warfare: in brief, for the traditional concerns of ancient historians. A second consideration is that biological anthropology is rooted in prehistory; its practitioners are characteristically involved in the exploration of the origins of humanity. Fortunately, some anthropologists have allowed themselves to stray into historical periods, including the classical world of Greece and Rome. In the meantime, historians of antiquity are showing increased interest in social, economic, and cultural history, and are displaying a new willingness to expose themselves to other disciplines, including the natural and social sciences. Thus, the time seems ripe for fruitful communication between historians and anthropologists. Specifically, health and demography (mortality, fertility, and mobility) hold promise as fields for constructive dialogue and collaborative research.Less