The erosive potential of some flavoured waters ated water is slightly more acidic at around 5.2.11 search Inc., Waltham, MA, USA) at 37°C on a heat- The effect of still and carbonated mineral water ed magnetic stirrer. The pH meter was calibrated on powdered enamel has been assessed using using test solutions of known pH (Fisher Scientific spectroscopy.11 It was found that these drinks had International, Loughborough, UK) before testing little erosive effect on enamel and carbonated wa- the drinks. Each drink was tested using five differ- ter produced a slightly greater dissolution effect ent samples. compared to still water, but this is very unlikely to be of clinical significance. Neutralisable acidity The pH of some flavoured waters were found to The neutralisable acidity of each drink was be more acidic than plain still or carbonated wa- tested by placing 20 mls of the drink in a glass ters, with a pH of around 3.3.11 However, the effect beaker placed in a thermostatically controlled of these drinks on enamel was not assessed. water bath held at 37°C. 0.1M sodium hydroxide The aim of this study was to compare a number solution was gradually added to the drink sample of commercially available flavoured waters and and the pH rise was continuously monitored until compare these with orange juice. The hypothesis the pH increased to neutrality. Each sample was used in this study was that the flavoured waters stirred continuously as the solution of sodium hy- would not be more erosive than orange juice. droxide was added. The volume of sodium hydrox- ide required to increase the pH of the sample to MAterIAls And Methods neutrality was noted; this was repeated five times for each drink. The flavoured waters chosen for inclusion in this study are listed in Table 1. These drinks were Enamel erosion chosen as they were readily available to the public. All measurements of enamel loss were made Three of the drinks were carbonated and these are using profilometry according to the method of indicated with an asterix in Table 1. The remaining West.12 The source of enamel was extracted un- drinks were still water products with no carbon- erupted third molar teeth from individuals residing ation. in a region with unfluoridated drinking water. Thus the level of fluoride incorporation into enamel was Initial pH anticipated to be low, but was not further charac- The pH of each of the drinks was tested using terised. The specimens were sectioned longitudi- an electronic pH meter (Model 701A, Orion Re- Table 1. Drink contents according to manufacturers’ information. Flavoured water Volvic Touch of Fruit still lemon and lime Contents Mineral water (92%), sugar, citric acid, lemon and lime natural flavours Boots Shapers still cranberry Spring water, apple juice from concentrate (13.5%), cranberry juice from juice spring water concentrate (6.5%), citric acid, flavourings, preservatives(E242, potassium sorbate, sodium benzoate), stabiliser (E466), sweeteners (sucralose), anti- oxidant (ascorbic acid), colour (anthocyanins), Vitamins E, B3, B6 and B12 Boots Shapers sparkling cloudy Carbonated spring water, lemon fruit from concentrate (3%), lemon juice lemonade spring water* from concentrate (1%), citric acid, flavourings, preservatives (potassium sorbate, sodium benzoate, sulphur dioxide), sweeteners (sucralose, acesul- fame K) Boots Shapers still Floridian orange juice spring water Volvic Touch of Fruit still orange and peach Carbonated spring water, Floridian orange juice from concentrate (18%), fruit from concentrate (2.5%), citric acid, flavourings, preservatives (E242, potassium sorbate, sodium benzoate), sweetener (sucralose), vitamins C, E and A Mineral water (92%), sugar, citric acid, orange and peach natural flavours Waitrose grapefruit spring water Carbonated spring water, grapefruit juice from concentrate, fructose, citric drink* acid, flavourings, sweetener (aspartame), preservative (sodium benzoate) Bottlegreen presselight elder- Carbonated spring water, cane sugar, elderflowers, citric acid, ascorbic flower* acid, preservative (sodium benzoate), sweetener (aspartame) * indicates carbonated drink European Journal of Dentistry