Sports and Energy Drink Mediated Erosion-attrition of Human Enamel

Objectives: To determine the effect of two sports and energy drinks on the erosion-attrition process on polished human enamel
Methods: Polished (n=40) human enamel samples were randomised to four experimental arms according to the erosion solution. They underwent five cycles of erosion-attrition consisting of immersion and agitation (n=10) in 80ml deionised water (negative control, pH 6.89), citric acid (positive control, pH 3.20), Lucozade (pH 3.34), Red Bull (pH 3.44), before undergoing attrition (300g loading force, 60 seconds) against enamel cusp antagonist. Change in mean(SD) surface profilometry (single mid-point step height change, µm) and Knoop surface microhardness change (KHN), were determined before and after acid erosion. Data were tested for normality before undergoing statistical analysis (one-way ANOVA intra-group analysis, two-way ANOVA inter-group analysis)
Results: Mean (SD) step height change (µm) after deionised water, citric acid, Lucozade, and Red Bull immersion was 1.0 (0.6), 17.0 (3.4), 15.1 (3.4), and 9.4 (4.5) respectively; statistically significant for all groups versus negative control (p<0.0001), Red Bull versus positive control (p<0.0001), and Red Bull versus Lucozade (p<0.005). There was no statistically significant difference between Lucozade and positive control (p>0.05)
Mean (SD) Knoop surface microhardness change after deionised water, citric acid, Lucozade, and Red Bull immersion was 68.2 (17.8), 93.5 (25.8), 120.0 (25.7) and 119.3 (15.1) respectively; statistically significant for all groups versus negative control (p<0.0001), Lucozade versus positive control (p<0.05). There was no statistically significant difference between Red Bull and Lucozade (p>0.05), and between Lucozade and positive control (p>0.05)
Conclusions: Lucozade and Red Bull produced detectable bulk enamel loss and significant surface softening changes in human enamel following an erosion-attrition model. Lucozade produced similar bulk enamel loss compared with citric acid positive control, whilst neither test solution produced differences in residual surface microhardness. This study provides insight into the erosive potential of common energy and sports drinks in an erosion-attrition model.