Monographs in oral science最新文献

Erosive demineralisation causes characteristic histological features. In enamel, mineral is dissolved from the surface, resulting in a roughened structure similar to an etching pattern. If the acid impact continues, the initial surface mineral loss turns into bulk tissue loss, and with time, a visible defect can develop. The microhardness of the remaining surface is reduced, increasing the susceptibility to physical wear. The histology of eroded dentine is much more complex because the mineral component of the tissue is dissolved by acids, whereas the organic part is remaining. At least in experimental erosion, a distinct zone of demineralised organic material develops, the thickness of which depends on the acid impact. This structure is of importance for many aspects, e.g., the progression rate or the interaction with active agents and physical impacts, and needs to be considered when quantifying mineral loss. The histology of experimental erosion is increasingly well understood, but there is lack of knowledge about the histology of in vivo lesions. For enamel erosion, it is reasonable to assume that the principal features may be similar, but the fate of the demineralised dentine matrix in the oral cavity is unclear. As dentine lesions normally appear hard clinically, it can be assumed that it is degraded by the variety of enzymes present in the oral cavity. Erosive tooth wear may lead to the formation of reactionary or reparative dentine.

Erosive tooth wear is a gene-environmental model. It requires the exposure to acids, typically from the diet or from the gastric content of the host, and shows variation among individuals and populations, which suggests it to be determined by more than one gene, each with small individual effects. This chapter expands the discussion that supports the assumption that a genetic component modulates the expression of erosive tooth wear.

Erosive tooth wear is increasingly encountered in clinical practice, yet its diagnosis and subsequent treatment planning can be ambiguous. Counselling and monitoring are advocated as the first intervention when managing patients with erosive tooth wear. However, some of them will invariably require restorative rehabilitation. Over the years, restorative care of the more severely worn dentition has shifted from the prescription of invasive, conventional prosthodontic protocols to the use of minimally invasive additive techniques. This has been facilitated by advances in dental adhesion and dental materials. This chapter provides an overview of a pragmatic philosophy for managing tooth wear, facilitating decision-making processes for these cases. It appraises concepts in tooth wear management from counselling and monitoring to restorative treatment, including the principles of planning where rehabilitation is indicated. This chapter also focuses on the application of direct resin composite for the treatment of tooth wear. It outlines some of the applied treatment techniques such as guided material placement and injection moulding that are being more commonly used in contemporary clinical practice. Additionally, it reviews the evidence base for the performance of these materials and techniques for managing erosive tooth wear, demonstrating how this information can lead to the attainment of more superior treatment outcomes. The impact of using direct composite on the patient's oral health-related quality of life is also discussed, emphasising its importance in obtaining consent for the restorative rehabilitation of the severely worn dentition.

The dynamic interplay of the oral fluids with the tooth surface is of essential relevance for the modulation of the de- and remineralization of tooth hard substances. It is generally accepted textbook knowledge that the buffering and clearance properties of the saliva are key factors in the prevention of erosive mineral loss. This becomes especially evident when the patients suffer from xerostomia. Furthermore, biomolecules in the oral fluids ensure the formation of the pellicle layer on all solid surfaces. While the enamel pellicle has been shown to diminish erosive attacks to a certain extent, it is unclear if the dentinal pellicle yields the same efficiency. In this context, two aspects seem to be marginalized in research: the dentine surface and the impact of protein adsorption and infiltration in demineralized tooth structures, despite the fact that both are essential for the understanding and modulation of erosive processes. Successful and sustainable prevention strategies are only possible if we understand these dynamic interactions. Therefore, future research should focus on the interaction of proteins with dentine and enamel during repeated de- and remineralization processes.

Various assessment techniques have been applied to evaluate the loss of dental hard tissue and the surface-softened zone in enamel induced by erosive challenges. In this chapter, the most frequently adopted techniques for analyzing the erosively altered dental hard tissues are reviewed, such as profilometry, measuring microscope techniques, microradiography, scanning electron microscopy, atom force microscopy, nano- and microhardness tests, and iodide permeability test. Moreover, methods for chemical analysis of minerals dissolved from dental hard tissue are discussed. It becomes evident that the complex nature of erosive mineral loss and dissolution might not be comprehended by a single technique, but needs application of different approaches for full understanding.

European and Chinese data suggest that dentine hypersensitivity (DH) is an ever increasing, significant oral pain condition, with adult population prevalence figures reaching 50%. Aetiology is multifactorial, with erosive tooth wear (ETW) becoming more important due to increased frequency of dietary acidic food and beverage challenges in younger adults. In older cohorts, DH prevalence increase is driven by population longevity, healthier lifestyles and higher vital tooth retention enduring a lifetime of tooth wear. DH negatively affects quality of life. For DH to occur, the lesion is localized on tooth crown and/or root surface, followed by initiation, exposing dentine tubules which are patent to the pulp, the key component to DH aetiology being ETW. Therapeutic strategies commence with risk assessment and instigation of preventive measures. Peer-reviewed, evidenced-based, efficacious dentifrice treatment regimens are now available, particularly over-the-counter home-use products, including arginine, stannous and potassium, with or without stannous, and resistant to acid challenge. Dentifrices should be regarded as the first-line treatment in conjunction with ETW preventive therapy. Professional treatment is the second-line approach, and although a plethora of agents have been advocated, there is weak evidence base for a preferred strategy. The ideal treatment should demonstrate immediate and long-lasting pain relief, with efficacious dentifrices showing variable degrees of pain relief commencing immediately to up to 2 weeks. The basic principles of treatment involve altering dentinal tubule fluid flow with dentine tubule occlusion or surface coverage and are designed to withstand ETW or chemically blocking pulpal nerve response.

Tooth wear involves three processes. Abrasion is a form of three-body wear produced by abrasive components of slurries contacting the teeth (either food or, in modern Western populations, mainly toothpaste). Attrition is a form of two-body wear through tooth-tooth contact. Erosion is demineralization of hard tissue, caused by acidic ingested substances (foods, drinks or medications), by regurgitated gastric acid or by acidic industrial vapours. A further process (abfraction) is said to be caused by occlusal stresses, which might enhance wear in the cervical region by abrasion and/or erosion. A review of the knowledge on these tooth wear processes and their interactions is provided. Both clinical and experimental observations show that, in modern Western populations, individual wear mechanisms rarely act alone but interact with each other. The most important interaction is the potentiation of abrasion by erosive damage to the dental hard tissues ('softening'). This interaction seems to be the major factor in pathological wear of occlusal and cervical surfaces. The available evidence is insufficient to establish whether abfraction is an important contributor to tooth wear in vivo.

Any preventive measure or behaviour change from the patient can only be based on a thorough assessment of the factors involved in erosive tooth wear (ETW). Patient assessment, in turn, runs hand in hand with a good detection of the ETW lesions and their progression. This chapter presents an overview of how to assess ETW lesions, monitor their progression and assess the factors related to the condition, in order to discuss preventive measures. Clinical assessment can be made with clinical indexes, like the basic erosive wear examination, while monitoring can also include accessory methods, like photographs, casts, intra-oral scanning, etc. Ideally, ETW lesions should be detected in their early stages, which will then prompt the health professionals to identify the factors involved in the condition. For that, dental health professionals can make use of dietary assessments and verify salivary parameters, eating disorders and gastroesophageal reflux disease. Susceptible patients, like those who use drugs and specific medications and/or who are exposed to environmental or occupational threats, should also be assessed. Once the factors are identified to each individual case, preventive measures can then be tailored to each patient, to hinder the progression of lesions and/or to deal with any dentine hypersensitivity arising from exposed dentine.

Factors related to the development of erosive tooth wear (ETW) over a lifetime can largely be divided into dietary, environmental and/or patient related. As the properties of the teeth change over time, these factors will be involved at different ages, and the susceptibility to ETW will vary according to age. Based on the available literature, dietary acid is the most important determinant of ETW. Various eating/drinking habits and oral hygiene routines are considered moderate factors in children and minor factors in adults. Medications and use of illicit drugs in adolescents and adults are potentially moderate factors in ETW and are often associated with confounding factors that drive the wear process forward. Some environmental and occupational factors in adolescents and adults can also be associated with ETW, particularly in special groups such as professional/competitive swimmers or other elite athletes and factory workers. Medical conditions such as gastro-oesophageal reflux disease and eating disorders are considered possible ETW factors in the primary dentition and major factors in the permanent dentition. The quality and quantity of saliva and pellicle may play a role in ETW, although salivary composition and flow rate can change over a lifetime. In conclusion, dental health professionals should be aware of the various factors that can be related to the development of ETW during a lifetime. Patients should be provided with relevant information about these factors, as well as recommendations for preventing and/or reducing/adjusting these factors.