title: The effect of Coca-Cola and fruit juices on the surface hardness of glass-ionomers and 'compomers'.
abstract: The interaction of tooth-coloured dental restorative materials (a conventional glass-ionomer, two resin-modified glass-ionomers and two compomers) with acidic beverages has been studied with the aim of investigating how long-term contact affects solution pH and specimen surface hardness. For each material (ChemFil Superior, ChemFlex, Vitremer Core Build-Up/Restorative, Fuji II LC, Dyract AP and F2000) disc-shaped specimens were prepared and stored in sets of six in the following storage media: 0.9% NaCl (control), Coca-Cola, apple juice and orange juice. After time intervals of 1 day, 1 week, 1 month, 3 months, 4 months, 6 months and 1 year, solution pH and Vickers Hardness Number were determined for each individual specimen. Differences were analysed by anova followed by Student-Newman-Keuls post hoc analysis. All materials were found to reduce the pH of the 0.9% NaCl, but to increase the pH of the acidic beverages. The conventional glass-ionomers dissolved completely in apple juice and orange juice, but survived in Coca-Cola, albeit with a significantly reduced hardness after 1 year. The other materials survived in apple juice and orange juice, but showed greater reductions in surface hardness in these beverages than in Coca-Cola. Fruit juices were thus shown to pose a greater erosive threat to tooth coloured materials than Coca-Cola, a finding which is similar to those concerning dentine and enamel towards these drinks.
authors.affiliation: Guy's, King's and St Thomas' Dental Institute, King's College, Guy's Hospital, London, UK.
authors.forename: M
authors.initials: M
authors.lastname: Aliping-McKenzie
authors.forename: R W A
authors.initials: RW
authors.lastname: Linden
authors.forename: J W
authors.initials: JW
authors.lastname: Nicholson
mesh_terms: D001628:Beverages; D002957:Citrus / Q000737:chemistry*; D003188:Composite Resins / Q000737:chemistry*; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006244:Hardness; D006801:Humans; D008422:Materials Testing; D014077:Tooth Erosion / Q000209:etiology
chemical_list: D003188:Composite Resins; D005899:Glass Ionomer Cements