ABSTRACT
Objectives: This in vitro study evaluated the capability of different soft drinks
(Coca-Cola® -C, Coca- Cola Light® -CL, Guaraná® -G, Pepsi Twist® -P and Sprite
Light® -SL) to erode dental enamel, relating the percentage of superficial microhardness
change (%SMHC) to concentrations of fluoride and phosphate, buffering capacity
and pH of these drinks.
Methods: The soft drinks were evaluated in respect to concentration of phosphate and
fluoride spectrophotometrically using Fiske, Subarrow method and by specific
electrode (Orion 9609), respectively. The pH and the buffering capacity were
determined by glass electrode and by estimating of the volume of NaOH necessary
to change the pH of the drink in one unit, respectively. One hundred specimens
of bovine enamel were randomly assigned to 5 groups of 20 each. They were exposed
to 4 cycles of demineralisation in the beverage and remineralisation in artificial
saliva. The softening of enamel was evaluated by %SMHC.
Results: The mean %SMHC was:C=77.27%, CL= 72.45%, SL=78.43%, G=66.65% and P=67.95%.
Comparing the %SMHC promoted by 5 soft drinks, SL = C > CL > P = G (P<.05). There
was not significant correlation between %SMHC and the other variables tested
for the five drinks (P>>.05)
Conclusions: The five soft drinks caused surface softening of enamel (erosion). In
respect to the chemical variables tested, despite not statistically significant,
the pH seems to have more influence on the erosive potential of these drinks.
(Eur J Dent 2007;1:10-13)
Key words
Tooth erosion - Carbonated beverages - Dental enamel
