Are soft drinks soft on teeth? A study on dental erosion caused by soft drinks marketed in India

Introduction: Awareness of dental erosion by public is still not widespread, and there is paucity of information on how much erosion do various soft-drinks marketed in India cause.Objectives: To quantify the amount of erosion that various soft-drinks may cause, in relation to their baseline pH, titrable acidity and calcium contents.Method: Six types of drinks-Coca-cola, Sprite, Maaza, Lipton iced lemon tea, Tropicana orange juice and yoghurt were used, with water as control. Baseline pH was determined by pH electrode, baseline titrable acidity was determined by amount of sodium hydroxide (NaOH) required for making pH of 5.5 and calcium content by Atomic Absorption Spectrophotometry. Five teeth each of maxillary premolars were randomly allocated into each of 7 groups. After incubation in 100 ml for 2 hours, 12 hours and 24 hours, amounts of calcium released was determined.Results: Mean calcium release after 24 hours was highest for Coca-cola with lowest pH, followed by Maaza, Sprite, Orange juice, Lemon tea, yoghurt and water, which released 1.38µg/ml/mm ² , 1.28µg/ml/ mm ² , 1.04µg/ml/mm ² , 0.91µg/ml/mm ² , 0.49µg/ml/mm ² , 0.34µg/ml/mm ² and 0µg/ml/mm ² of calcium respectively. Statistically significant differences were found for calcium release in coca-cola, maaza, sprite and orange juice from baseline to 2, 12 and 24 hours (p-value < 0.00).Conclusion: Beverages with lower baseline pH and lower baseline calcium concentration showed higher calcium release. Though, direct application of the results of this study to in-vivo conditions cannot be fully made due to other host and dietary factors.