A Brief History of Tooth Wear.

Historical publications that have significantly improved the understanding of tooth wear mechanisms are reviewed with a focus on descriptions of the lesions, the evolution of their classification systems, and considerations addressing the main risk factors. Surprisingly, most important advances are often the oldest. Likewise, they are currently only marginally known, which requires a major dissemination effort.

Epidemiology, aetiology and prevention of tooth wear.

Tooth wear is a commonly reported finding globally; however, many patients are unaware of having tooth wear. Identifying early signs of erosion, abrasion or attrition and determining the risk factors contributing to a patient's tooth wear may help to prevent further loss of enamel and dentine in the future. Appropriate prevention should be instigated, or appropriate referral made to other health professionals, when conditions such as gastroesophageal reflux or eating disorders are suspected. This paper presents the epidemiology and aetiological factors for tooth wear, as well as identifying the common clinical presentations of tooth wear. Patient perspectives on tooth wear and preventive techniques that can be utilised are also discussed.

Lesões cervicais não cariosas: considerações etiológicas, clínicas e terapêuticas / Lesiones cervicales no cariosas: consideraciones etiológicas, clínicas y terapéuticas / Non-carious cervical injuries: etiological, clinical and therapeutic considerations

RESUMO Introdução: As lesões cervicais não cariosas são lesões dentárias, que apresentam etiologia multifatorial, sem o envolvimento de bactérias. Objetivo: Descrever as características clínicas, etiologia e tratamento das lesões cervicais não-cariosas. Métodos: Realizou-se uma revisão bibliográfica de estudos publicados nos últimos 5 anos (2014-2018) por meio da busca nas bases de dados: PubMED/Medline, Lilacs, Science Direct, SciELO (Scientific Eletronic Library) e Google Acadêmico. Para a pesquisa foram utilizados os seguintes descritores: "lesões cervicais não cariosas (non-carious cervical lesions)", "abrasão dentária (dental abrasion)", "erosão dentária (dental erosion)", "abfração dentária (dental abfraction)" e "atrição dentária (dental atrittion). Após criteriosa filtragem, foram selecionados 26 artigos e 2 livros para inclusão no estudo. Análise e integração das informações: As lesões cervicais não cariosas comumente classificadas em: abrasão, abfração, erosão e atrição. Essas lesões podem apresentar diversas formas, apesar de serem incluídas em uma classe genérica de denominação. São lesões que causam a perda gradativa dos tecidos mineralizados dentários, podendo trazer inúmeras consequências ao dente acometido. Conclusão: Para um correto diagnóstico e decisão de tratamento, essas lesões devem ser vistas sob seu aspecto etiológico multifatorial. Diversas possibilidades terapêuticas podem ser utilizadas no tratamento dessas lesões sendo necessário que o clínico conheça os principais fatores etiológicos e características clínicas que as diferenciem(AU)

RESUMEN Introducción: Las lesiones cervicales no cariosas son lesiones dentales, que presentan etiología multifactorial, sin la participación de bacterias. Objetivo: Describir las características clínicas, etiología y tratamiento de las lesiones cervicales no cariosas. Métodos: Se realizó una revisión bibliográfica de estudios publicados en los últimos 5 años (2014-2018) a través de la búsqueda en las bases de datos: PubMED / Medline, Lilacs, Science Direct, SciELO (Scientific Eletronic Library) y Google Académico. Para la investigación se utilizaron los siguientes descriptores: "lesiones cervicales no cariosas", "abrasión dental", "erosión dental", "abfracción dental" y " " atrición dental. Después de un cuidadoso filtrado, se seleccionaron 26 artículos y 2 libros para su inclusión en el estudio. Análisis e integración de las informaciones: Las lesiones cervicales no cariosas comúnmente clasificadas en: abrasión, abfración, erosión y atrición. Estas lesiones pueden presentar diversas formas, aunque se incluyen en una clase genérica de denominación. Son lesiones que causan la pérdida gradual de los tejidos mineralizados dentales, pudiendo traer innumerables consecuencias al diente acometido. Conclusiones: Para un correcto diagnóstico y decisión de tratamiento, estas lesiones deben ser vistas bajo su aspecto etiológico multifactorial. Diversas posibilidades terapéuticas pueden ser utilizadas en el tratamiento de esas lesiones, por lo que resulta necesario que el clínico conozca los principales factores etiológicos y características clínicas que las diferencien(AU)

ABSTRACT Introduction: Non-carious cervical lesions are dental lesions of a multifactorial etiology, without the involvement of bacteria. Objective: Describe the clinical characteristics, etiology and treatment of non-carious cervical lesions Methods: A bibliographic review was conducted of studies published in the last five years (2014-2018) by searching the databases PubMED / Medline, Lilacs, Science Direct, SciELO (Scientific Electronic Library) and Google Scholar. The following descriptors were used: "non-carious cervical lesions", "dental abrasion", "dental erosion", "dental abfraction" and "dental attrition. After careful filtering, 26 articles and two books were selected for inclusion in the study. Data analysis and integration: Non-carious cervical lesions are commonly classified as abrasion, abfraction, erosion and attrition. These lesions may present various forms, but they are all grouped in a single generic class. They are lesions that cause the gradual loss of mineralized dental tissue, which may bring countless consequences to the affected tooth. Conclusions: For a correct diagnosis and treatment decision, these lesions must be seen under their multifactorial etiological aspect. Various therapeutic possibilities may be used in the treatment of these lesions, and it is necessary for the clinician to know the main etiological factors and clinical characteristics that differentiate them(AU)

Phenotypes of patients with extensive tooth wear-A novel approach using cluster analysis.

OBJECTIVES: Explore a new approach to identify phenotypes of tooth wear (TW) patients using an unsupervised cluster analysis model, based on demographic, self-report, clinical, salivary and electromyographic (EMG) findings. METHODS: Data was collected for 34 variables from 125 patients, aged 17-65 years, with a TW index > grade 2. Demographic information and presumed risk factors for chemical and mechanical TW were collected. A 14-item stress scale was completed and salivary flow rates, pH and buffer capacity were measured. Sleep bruxism was assessed with a portable single channel EMG device. RESULTS: The final cluster model comprised 16 variables and 103 patients and indicated two groups of TW patients; 61 participants in cluster A and 42 in cluster B. Cluster assignment was determined by several presumed mechanical risk factors and diseases affecting saliva. Cluster B had the highest percentage of sleep bruxism self-reports (A 1.6%, B 92.9%, p ≤ 0.001), awake bruxism self-reports (A 45.9%, B 85.7%, p ≤ 0.001), heavy sport exercises (A 1.6%, B 21.4%, p = 0.001); and highest percentage of diseases affecting saliva (A 13.1%, B 47.6%, p ≤ 0.001). A notable finding was the lack of significant differences between clusters in many other presumed risk factors for mechanical and chemical TW. CONCLUSION: TW patients can be clustered in at least two groups with different phenotypic characteristics but also with a large degree of overlap. Based on this type of algorithm, tools for clinical application may be developed and underpin TW classification and treatment planning in the future.

A guide to the clinical management of attrition.

Attrition is an enigmatic condition often found in older individuals and often as a result of bruxism which can take place as a result of either day bruxism, night bruxism or both. Various studies and systemic reviews clearly shown that tooth wear is an age-related phenomena and the last Adult Dental Health Survey showed that 15% of participants showed moderate wear and 3% severe wear with 80% of patients over 50 years of age showing signs of wear. This review examines current theories around the aetiological factors contributing to attrition together with the clinical management of attrition focusing on minimal intervention where possible.

Lesiones cervicales no cariosas / Non-carious cervical lesions

El objetivo de este trabajo consiste en describir las distintas lesiones cervicales no cariosas, la abrasión, la erosión y la abfracción. Se desarrollarán en detalle su etiología, localización y características clínicas. Se mencionarán los diferentes procedimientos a realizar para su prevención y los materiales a utilizar para su restauración.

This article describes the different types of non-cariouscervical lesions, for example abrasion, erosionand abfraction. We will discuss their etiology, location and clinical features in detail. We will describe the procedures to prevent them, aswell as the materials used for their restoration.

Non-carious cervical lesions imaged by focus variation microscopy.

OBJECTIVE: The aim of this study is to characterize the morphological and histological features of NCCLs in a group of extracted teeth using a focus variation optical microscopic technique that is capable of detecting minute variation in surface topography. METHODS: Twenty three extracted teeth containing NCCLs were collected. Histological features of the surface and longitudinal cross sections were examined using a focus variation microscope (FVM). RESULTS: The sample included 8 teeth with wedge-shaped lesions; the remaining 15 contained saucer-shaped lesions. Wedge-shaped lesions showed obliterated dentinal tubules, parallel furrows and micro-fractures in the surface; longitudinal cross sections revealed subsurface micro-fractures extending toward the pulp chamber. The surfaces of typical saucer-shaped lesions were smooth and relatively featureless. CONCLUSIONS: FVM imaging shows microstructures that are consistent with simultaneous erosion and toothbrush abrasion. Saucer shaped lesions have a smooth featureless surface as well as craters and dimples that could be attributed to uneven acid attack. In wedge-shaped lesions, the presence of scratches and furrows could be attributed to mechanical forces such as tooth brush abrasion. The furrows and in-surface micro-factures of wedge shaped lesions suggest a possible role of tensile stresses but require further investigation. CLINICAL SIGNIFICANCE: NCCLs present in two morphologies, either saucer-shaped or wedge-shaped. Erosion and toothbrush abrasion are important in both types of lesions. Tensile stresses due to occlusal loading may be important in some wedge-shaped lesions. Knowing the etiology of cervical lesions is the key for their prevention.

Mandibular movement during sleep bruxism associated with current tooth attrition.

PATIENT: Observation of attrition patterns suggests that mandibular movement in sleep bruxism (SB) may be associated with current tooth attrition. The aim of this study was to confirm this phenomenon by investigating mandibular movement and masseter muscle activity. The subject was a healthy 21-year-old Japanese male. We recorded biological signals including mandibular movement and masseter electromyograms (EMGs) with a polysomnograph. Based on the EMG using Okura's criteria, SB events were classified into clenching, grinding and mixed types according to mandibular movement criteria. The close-open mandibular movement cycles (CO-cycles) during grinding and mixed type events were selected based on mandibular movement trajectories. DISCUSSION: Fifty-eight CO-cycles were selected in seven grinding and three mixed types. We found that SB mandibular movements associated with current tooth attrition. Excessive lateral movements (ELM) beyond the canine edge-to-edge position were observed in the closing (10.3%) and opening (13.8%) phases of the CO-cycle. Total masseter muscle activity was significantly higher during voluntary grinding (VGR) than during CO-cycle including ELM (working side: P=0.036, balancing side: P=0.025). However, in the middle and late parts of the opening phase, working side masseter muscle activity was significantly higher during CO-cycle including ELM than during VGR (P=0.012). In the early part of the closing phase, balancing side masseter muscle activity was significantly higher during CO-cycle including ELM than during VGR (P=0.017). CONCLUSION: These findings suggest that excessive forceful grinding during ongoing SB events may have caused canine attrition in this patient.

Long-Term Provisional Bonded Composite Restorations Make Full-Mouth Rehabilitation Possible.

Full-mouth rehabilitation cases frequently require an extended period to complete. In this case involving a patient who presented with a significant amount of lost tooth structure, treatment featured laboratory-fabricated composite provisional restorations aimed at stabilizing the dentition and enabling definitive treatment to be completed in segments. The approach taken allowed occlusal and esthetic issues to be resolved through use of the provisionals while minimizing tooth preparation. The technique provided immediate improvement in esthetics, function, and comfort.

Direct Placement Composite: the Treatment Modality of Choice to Restore the Worn or Eroded Dentition in Primary Dental Care.

Tooth wear is increasing in severity and prevalence, partly because of an ageing population and partly because of modern lifestyles. Management of the worn dentition with 'full mouth rehabilitation' is outmoded. This clinical paper aims to review the literature on composite restorations and give general dental practitioners the confidence to restore the worn dentition with dental composite. Composite is a versatile and widely available material that can be successfully applied within the existing occlusal vertical dimension (OVD) or at an increased OVD using a Dahl approach. Cases illustrate what is achievable, and clinical tips will help dentists optimise their results.

Treating Tooth Surface Loss: Adhesive Restoration of the Worn Anterior Dentition.

The treatment of tooth surface loss (TSL) is becoming more common in primary health care and a diverse variety of patients are presenting with this condition are often being treated by general dental practitioners. This article highlights the importance of comprehensive planning and adept execution that can enhance the patient's outcome and experience. Stages of clinical planning and treatment approaches using a selection of restorative materials utilising various established adhesive clinical techniques will be presented and discussed.

The tooth wear evaluation system: a modular clinical guideline for the diagnosis and management planning of worn dentitions.

Tooth wear is a multifactorial condition, leading to the loss of dental hard tissues, viz. enamel and dentine. Tooth wear can be divided into the subtypes mechanical wear (attrition and abrasion) and chemical wear (erosion). Because of its multifactorial aetiology, tooth wear can manifest itself in many different representations, and therefore, it can be difficult to diagnose and manage the condition. A systematic approach is a sine qua non. In the below-described tooth wear evaluation system (TWES), all necessary tools for a clinical guideline are present in different modules. This allows the dental clinician, in a general practitioner setting as well as in a referral practice setting, to perform a state-of-the-art diagnostic process. To avoid the risk of a too cumbersome usage, the dental clinician can select only those modules that are appropriate for a given setting. The modules match with each other, which is indispensable and essential when different modules of the TWES are compared. With the TWES, it is possible to recognise the problem (qualifying), to grade its severity (quantifying), to diagnose the likely causes and to monitor (the progress of) the condition. In addition, a proposal for the classification of tooth wear is made. Further, it is possible to determine when to start a treatment, to make the decision which kind of treatment to apply and to estimate the level of difficulty of a restorative treatment.

Risk Assessment for Tooth Wear.

Tooth wear has an increasing prevalence in the UK population. The aetiology is commonly multifactorial, and the aetiopathology is through a combination of erosion, attrition, abrasion and abfraction. Erosion is associated with intrinsic or extrinsic acids, and therefore subjects with reflux disease and eating disorders are at increased risk. Fruit juice, fruits and carbonated drink consumption, frequency of consumption and specific habits are also risk factors. Attrition is more prevalent in bruxists. Other habits need to be considered when defining the risk of tooth wear. Abrasion is usually associated with toothbrushing and toothpastes, especially in an already acidic environment. Patients with extensive lesions that affect dentin may be at higher risk, as well as those presenting with unstained lesions. Monitoring of the progress of tooth wear is recommended to identify those with active tooth wear. Indices for tooth wear are a helpful aid.

Worn Down by Toothwear? Aetiology, Diagnosis and Management Revisited.

The incidence of toothwear in the population is increasing, as is the number of referrals regarding this problem to secondary care dental hospital consultants and specialists. This paper outlines current theories in aetiology, diagnosis and management of localized and generalized toothwear, as well as describing clinical tips for assessing such patients.

Enamel mineral loss.

OBJECTIVES: To summarise the chemical, biological and host factors that impact enamel mineral loss, to highlight approaches to contemporary management of clinical conditions involving mineral loss and summarise emerging trends and challenges in this area. DATA SOURCES: "Medline" and "Scopus" databases were searched electronically with the principal key words tooth, enamel, *mineral*, caries and erosion. Language was restricted to English and original studies and reviews were included. Conference papers and abstracts were excluded. CONCLUSIONS: Enamel mineral loss leads to the degradation of the surface and subsurface structures of teeth. This can impact their shape, function, sensitivity and aesthetic qualities. Dental caries is a multifactorial disease caused by the simultaneous interplay of dietary sugars, dental plaque, the host and time. There is a steady decline in dental caries in developed countries and the clinical management of caries is moving towards a less invasive intervention, with risk assessment, prevention, control, restoration and recall. Tooth wear can be caused by erosion, abrasion and attrition. Dental erosion can be the result of acid from intrinsic sources, such as gastric acids, or extrinsic sources, in particular from the diet and consumption of acidic foods and drinks. Its prevalence is increasing and it increases with age. Clinical management requires diagnosis and risk assessment to understand the underlying aetiology, so that optimal preventative measures can be implemented. Overall, prevention of enamel mineral loss from caries and tooth wear should form the basis of lifelong dental management. Evidence based oral hygiene and dietary advice is imperative, alongside preventive therapy, to have a healthy lifestyle, whilst retaining hard tooth tissue.

Developmental enamel defects in the primary dentition: aetiology and clinical management.

Developmental enamel defects, presenting as enamel hypoplasia or opacities are caused by damage or disruption to the developing enamel organ as a result of inherited and acquired systemic conditions. The high prevalence of these defects in the primary dentition demonstrates the vulnerability of the teeth to changes in the pre- and postnatal environment. The presence of enamel hypoplasia increases the risk of primary teeth to early childhood caries and tooth wear as the defective enamel is thinner, more plaque retentive and less resistant to dissolution in acid compared to normal enamel. The purpose of this paper was to critically review the aetiology and clinical complications of developmental enamel defects in the primary dentition and propose recommendations for the clinical management of affected teeth.