Supplementation of soft drinks with metallic ions reduces dissolution of bovine enamel

OBJECTIVE:

The aim of this study was to evaluate the effect of the addition of metallic ions to carbonated drinks on their erosive potential.

MATERIAL AND METHODS:

Powdered enamel was added to carbonated beverages (Coca-Cola^TM or Sprite Zero^TM and shaken for 30 s. The samples were then immediately centrifuged and the supernatant removed. This procedure was repeated 5 times with the beverages containing Cu²⁺, Mg²⁺, Mn²⁺ or Zn²⁺ (1.25-60 mmol/L). For Coca-Cola^TM, the concentration of each ion that exhibited the highest protection was also evaluated in combination with Fe²⁺. The phosphate or calcium released were analyzed spectrophotometrically. Data were analyzed using ANOVA and Tukey's test (p<0.05).

RESULTS:

For Coca-Cola^TM, the best protective effect was observed for Zn²⁺ alone (10 mmol/L) or in combination (1 mmol/L) with other ions (12% and 27%, respectively, when compared with the control). Regarding Sprite Zero^TM, the best protective effect was observed for Cu²⁺ at 15 and 30 mmol/L, which decreased the dissolution by 22-23%. Zn²⁺ at 2.5 mmol/L also reduced the dissolution of powdered enamel by 8%.

CONCLUSIONS:

The results suggest that the combination of metallic ions can be an alternative to reduce the erosive potential of Coca-Cola^TM. Regarding Sprite Zero^TM, the addition of Cu²⁺ seems to be the best alternative.

Tooth erosion; Carbonated beverages; Zinc; Copper; Manganese; Magnesium