ABSTRACT
Objective: To investigate the influence of the erosive potential of Amazonian fruits on the bovine enamel microhardness. Material and Methods: A total of 30 healthy bovine incisors were divided into three groups, according to the Amazonian fruit juice used in the erosive challenge: Group A - taperebá (Spondias mombin), Group B - cupuaçu (Theobioma gandiflorum) Group C - graviola (Annona muricata), with n=10. The planning of specimens polishing was performed with decreasing grain sandpaper. Specimens were submitted to microhardness initial reading carried out in microhardness meter using Knoop indenter, using load of 50g for 15 sec. Three indentations were performed on reference surfaces with a distance of at least 100 µm from each other. Specimens were stored in distilled water up to the erosive challenge, which consisted of three steps: (1) 5-minute immersion in 10 ml of acid juice; (2) washing with distilled water and mild drying with tissue paper; (3) 60-minute immersion in 10 ml of artificial saliva. Subsequently, samples were stored in distilled water for reading of the final microhardness, after erosive challenge. Data were analyzed by ANOVA with α=0.05.. Results: All groups showed a statistically significant reduction in Knoop microhardness (KHN) after erosive challenge (p<0.0001). Group B showed the lowest average KHN (113.6) after erosive challenge, though not statistically different from Groups A and C (p=0.1592). Conclusion: Juices of fruits evaluated significantly changed the dental enamel hardness, and cupuaçu juice (Theobioma gandiflorum) caused the greatest surface hardness loss.