Effect of acidic food and drinks on surface hardness of enamel, dentine, and tooth-coloured filling materials

Objectives The purpose of this study was to determine the effect of acidic food and drinks (Cola soft drink, drinking yogurt, orange juice, sports drink, Tom-yum soup) on surface hardness of various substrates (enamel, dentine, universal composite, microfilled composite, conventional glass ionomer, resin-modified glass ionomer, polyacid-modified resin composite). Methods Specimens (n=10) were alternately immersed, 5 s each, in food or drinks and in artificial saliva for 10 cycles. Baseline and post-immersion Vickers hardness were compared using paired t-test. The difference in hardness between the groups was analysed with one-way ANOVA followed by a least significant different (LSD) test. Results Cola soft drink significantly reduced surface hardness of enamel, dentine, microfilled composite, and resin modified glass ionomer (p<0.05). Orange juice and sports drink significantly reduced surface hardness of enamel (p<0.05). Drinking yogurt and Tom-yum soup did not reduce surface hardness of any substrate. Conclusion This in vitro study confirms the erosive potential of certain acidic food and drinks that public should be aware of.