Protective effect of cocoa antioxidant extract in distinct vehicles on dentin erosion in vitro.

Abstract

This study aimed to conduct an in vitro evaluation of the antierosive potential of a solution and an experimental toothpaste enriched with natural antioxidants derived from cocoa (Theobroma cacao L.) on eroded dentin. Cocoa beans underwent fermentation, drying, roasting, grinding, and freeze-drying to obtain an aqueous cocoa extract. The extract was analyzed for total polyphenols and antioxidant capacity using the oxygen radical antioxidant capacity (ORAC) assay. A control toothpaste was then formulated and enriched with the concentrated cocoa extract. Eighty bovine dentin specimens were pre-eroded in citric acid and randomized into four groups (n = 20): G1 (negative control) - toothpaste without active ingredients; G2 - concentrated cocoa polyphenol solution; G3 - experimental toothpaste enriched with cocoa polyphenols; and G4 (positive control) - Elmex Protect commercial toothpaste (Colgate). Specimens underwent 3 days of erosive cycling. Surface loss (dSL-eroded) was measured by optical profilometry; collagen degradation (dColl) was calculated after collagenase exposure; and calcium release (CaR) was quantified by atomic absorption spectrometry. Surface morphology was qualitatively assessed by scanning electron microscopy (SEM). Data were analyzed by one-way ANOVA and Tukey's test (α=0.05). The cocoa extract showed higher levels of total polyphenols than did the enriched toothpaste (p = 0.037). Antioxidant activity decreased after toothpaste manipulation (p = 0.025). G2 exhibited significantly lower dSL-eroded, dColl, dSL-total, and calcium release compared with the other groups (p<0.05). SEM analysis of G3 revealed partially or totally occluded dentinal tubules. In conclusion, cocoa extract exhibited a higher polyphenol content and significant antierosive effects, leading to reduced dentin surface loss and enhanced tubule occlusion.