buffering capacity – Saliva and the fluid in dental plaque possess the ability to buffer. Buffering adjusts the pH of any solution such as saliva or plaque fluid, and can resist changes in pH. Buffering capacity is the degree of buffering that can be brought about.
chelation – As it applies to the oral cavity, chelation is the process whereby citric acid has the ability to demineralise enamel to a much greater degree than its pH can explain. Through its chelating properties, citric acid removes calcium from the enamel surface, and through chelation forms a compound from which the calcium cannot be released. Therefore, the calcium is not available to diffuse back into the tooth. Citric acid also has the ability to chelate calcium in saliva, reducing the remineralising effect.
demineralisation – The chemical process by which minerals (mainly calcium) are removed from the dental hard tissues – enamel, dentine, and cementum. The chemical process occurs through dissolution by acids or by chelation, and the rate of demineralisation will vary due to the degree of supersaturation of the immediate environment of the tooth and the presence of fluoride. In optimal circumstances, the minerals may be replaced through the process of remineralisation.
dentine hypersensitivity – Tooth pain that is characterised by brief, sharp, well-localized pain in response to thermal, evaporative, tactile, osmotic, or chemical stimuli that cannot be ascribed to any other dental disease or condition. Exposed dentine is a feature, and therefore the condition is associated with enamel wear (usually erosion) or gingival recession.
developed countries – A term not frequently used today in classifying countries, as no definitive definition exists. The term is used to describe countries with industrialised economies and higher levels of gross domestic product. Developed countries are able to spend more on health systems. These systems are typically treatment-oriented and focus services on the needs of the individual rather than the community.
erosion – Localised loss of oral hard tissues that is chemically etched away from the tooth surface by acids or chelating agents. Can be referred to as Acid Erosion or Acid Wear. Teeth exhibiting signs of erosion lose their surface texture (perichymata), may appear more yellow, and have an altered shape.
fluorapatite – A crystal structure in tooth mineral (Ca10 (PO4)6 F2) resulting from the replacement of hydroxyl ions (OH-) in the hydroxyapatite structure with fluoride ions (F-). Fluorapatite (also commonly referred to as fluoroapatite, fluorhydroxyapatite or fluorohydroxyapatite) is stronger and more acid resistant than hydroxyapatite.
GERD – Gastroesophageal reflux disease; the reflux of hydrochloric acid generated in the stomach that travels to the mouth. Erosion will occur upon the acid’s contact with enamel surfaces.
hydroxyapatite – Crystals of calcium phosphate – (Ca10 (PO4)6 OH2) that form the mineral structure of teeth and bone. Enamel comprises approximately 98% hydroxyapatite (by weight). Much of the hydroxyapatite in enamel, however, is a calcium-deficient carbonated hydroxyapatite, the crystals of which are readily dissolved by acids. The addition of fluoride creates fluorapatite, which is less soluble and more acid-resistant.
ions - Atoms or molecules that carry either a positive or a negative electric charge in a solution. For example, sodium chloride (NaCl, common table salt) in water dissociates into Na+ and Cl– ions.
prevalent – Widespread; widely or commonly occurring.
remineralisation – The chemical process by which minerals (mainly calcium) are replaced into the substance of the oral hard tissues – enamel, dentine and cementum. The process requires an ideal environment that includes supersaturation with calcium and phosphate ions, and adequate buffering. In the presence of fluoride, remineralisation is enhanced.
tooth wear – The non-carious loss of tooth tissue through the processes of attrition, abfraction, abrasion, or erosion, occurring alone or combined (most typically abrasion and erosion).
xerostomia – A subjective assessment of mouth dryness, usually but not always associated with low levels of saliva production. Inadequate production of saliva occurs for many reasons, most commonly as an unwanted effect of many prescription and over-the-counter medicines. Saliva is necessary for maintaining a healthy mouth, and, in relation to dental caries, is essential for remineralisation.