Dental lesions associated with exogenous and endogenous acids

Dental pathology related to acid and particularly to supraglottic gastro-oesophageal reflux is largely unknown in gastroenterology, including for endoscopists who nevertheless operate through the open mouth. Currently well defined and very recognisable, the prevalence and frequency of these erosive lesions has barely been studied, while at an advanced stage they are irreversible. Early diagnosis is thus indispensable. The destruction of calcified dental tissues by mechanisms other than the carie is covered under the general terms of wear or noncarious lesions. Mechanical wear due to tooth-tooth contact (antagonist teeth) affects the occlusal faces of the posterior teeth and the incisor edges of anterior teeth. It constitutes attrition. Bruxism is the main cause. Mechanical wear provoked by elements introduced into the oral cavity is called abrasion. Classically, pathological abrasion is associated with inappropriate tooth-brushing: abrasive toothpaste, a hard toothbrush, and hard and predominantly horizontal brushing. It is generally located in the cervical region of the vestibular sides. Current opinion pleads in favour of a mixed etiology: chemical attack favouring the mechanical elimination of weakened enamel. The determining role of demineralisation of non-bacterial origin or erosion is becoming clearer. Erosion may be of an exogenous origin. Acids and chelators of alimentary origin (fruit juices, carbonated drinks, vegetables, etc.) are the main agents responsible. The frequency of ingestion and the duration that acid liquids remain in the oral cavity are determining factors. Endogenous erosion is provoked by the repeated presence of acid of gastric origin in the oral cavity. This is mainly from spontaneous vomiting and above all from provoked vomiting (anorexia and bulimia) or gastro-oesophageal regurgitation. The specific localisation of endogenous erosion at the level of the palatal side of anterosuperior teeth should draw the attention of the dentist who, based on in-depth anamnesis, can orient the patient towards the specialised physician concerned, very often a gastroenterologist. It is difficult to isolate the main etiology of wear, given the absence of the specificity of most of the initial lesions and their generally combined origin. It is capital, however, in order to prevent the progression of the lesions and preserve any restoration. According to the etiology (bruxism, inadequate oral hygiene, excessive consumption of acidic products, dietary behavioural problems, chronic alcoholism, gastro-oesophageal regurgitation...) the suppression of the initial cause may be more or less difficult to achieve. Beginning lesions are controllable in a non-invasive manner by the application of fluid resins and/or adhesives. Small lesions can still be treated by simple techniques of directly applying composite resins which restore the anatomy. In the case of extensive destruction, indirect methods of inlay/onlay, veneers and crowns are required. Regular follow-up is indispensable.