Tooth wear erosion

Current health promotions advise that ecstasy users should frequently consume sports type or fruit drinks to counteract dehydration and avoid ion imbalances. These particular drinks may be erosive to the teeth. Bruxism and trismus associated with ecstasy use can also contribute to tooth wear. 

The term tooth wear is commonly used to describe the loss of tooth hard tissue due to non-carious causes [1], This encompasses a variety of both chemical and mechanical causes of both intrinsic and extrinsic origin. The term tooth wear is preferred over some of the more precise definitions of individual hard tissue loss mechanisms, because it acknowledges the fact that wear is usually a multifactorial process one mechanism may dominate, but the overall wear is commonly due to the interaction between two or more wear mechanisms. In dentistry, the terms erosion, abrasion, attrition and abfraction are widely used to describe particular mechanisms of hard tissue loss. 

The mechanisms of tooth wear fall into two distinct types those of chemical origin (e.g. erosion) and those of physical origin (e.g. abrasion, attrition). In any individual, both chemical and physical insults to the tooth hard tissue will be present in some form or other, so tooth wear is the combined effect of these insults. Despite the clear definition of a number of distinct tooth wear mechanisms, it is uncommon to find a single wear mechanism present in the... 

Of particular note is the importance of erosion in accelerating tooth wear. The softening of enamel and dentine surfaces by erosive attacks from acid renders the surface extremely susceptible to mechanical attacks [9]. Abfraction is also an example of interaction between wear mechanisms, where abrasion and erosion may act in combination with cyclic loading and unloading to produce an overall wear effect. 

The surfaces of the mouth are coated with a layer of salivary proteins known as the acquired pellicle, which provides a protective effect from both chemical and mechanical attacks to the tooth surface. The pellicle layer both moderates diffusion of ions away from the tooth surface, thus inhibiting the dissolution of enamel by erosion, and provides a lubricating layer to protect from mechanical attacks [10, 11], It is known that dental prophylaxis and the use of regular oral hygiene procedures are able to reduce or remove the pellicle layer. However, recent evidence has shown that the pellicle is able to re-form very rapidly and thus, maintain a protective layer over the tooth surface [10]. For this reason, tooth wear studies performed in vivo or in situ, where the mediating effects of pellicle are present, will give a much more realistic assessment of tooth wear than in vitro studies. For a more detailed discussion on the effects of pellicle, see chapter 2. 

Smith BGN, Knight JK An index for measuring the wear of teeth. Brit Dent J 1984 156 435-438. Azzopardi A, Bartlett DW, Watson TF, Smith BGN A literature review of the techniques to measure tooth wear and erosion. Eur J Prosthodont Rest Dent 2000 8 93-97. 

Bartlett DW, Blunt L, Smith BGN Measurement of tooth wear in patients with palatal erosion. Brit Dent J 1997 182 179-184. 

Amaechi BT, Higham SM, Edgar WM Development of an in situ model to study dental erosion in Addy M, Embery G, Edgar WM, Orchardson R (eds) Tooth Wear and Sensitivity. Martin Dunitz, London, 2000, pp 141-152. 

A topic of increasing interest is tooth wear. Chapter 4 describes recent research on the influence of dental product use, diet and other natural factors, and the inter-relationship between abrasive wear and chemical erosion. After describing the various physical and chemical mechanisms implicated in tooth wear, the author discusses the laboratory, in situ, and clinical approaches used to investigate the condition, illustrated with selected examples. 

A property not listed in Table 5.14, but which is of paramount importance to this application, is wear rate. Wear rate was described briefly in Section 8.2.2, and those concepts apply here as well. As it applies to tooth enamel, abrasive wear occurs by fracture or chipping of the enamel, chemical erosion, which may arise due to acidic medications or drinks, dietary oxalate, or high oral hydrogen ion concentrations as a result of disease, physical erosion, or abrasion, which arises due to idiopathic mechanisms, dentrifices, toothbrushes, or abrasive diets. For example, the wear rate of enamel has been measured at about 10 ttm/hour due to brushing with a toothbrush and toothpaste for 86,400 strokes [7],... 

West NX, Maxwell A, Hughes JA, Parker DM, Newcombe RG, Addy M A method to measure clinical erosion the effect of orange juice consumption on erosion of enamel. J Dent 1998 26 329-335. Cowell CR An appliance for the study of tooth tissue in vivo. Brit Dent J 1974 137 61-62. Cowell CR, Allen RWB A comparison of dentine wear on prepared tooth sections in vivo using two toothpastes. Brit Dent J 1979 146 339-342. 

However, this view has been challenged. For example, Lee and Eakle [77] suggested that they arise from a combination of factors, of which occlusal stress is one, but with abrasion and erosion also playing a part. Similarly, Spranger [78] has proposed a combination of factors in the development of cervical lesions, and that the phenomenon is related to the tooth anatomy, occlusion and parafunction, all of which contribute to elastic deformation forces at the neck of the tooth and which are augmented by wear phenomena [78],... 

It has been suggested that erosion of this type may contribute to the development of non-carious cervical lesions because erosive agents enter the surface of the enamel through internal channels. Having done so, they would weaken the enamel by chemical attack from within. The resulting affected enamel would then be more susceptible to wear (tooth brush erosion) and fracture when loaded than unaffected enamel. This erosion might influence the formation of cervical lesions without having a primary role in their occurrence. 

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