Method: Thirty male Wistar rats were divided into three groups (n=10). Rats of negative control (G1) received tap water and were not induced to stress. G2 and G3 received an isotonic solution [Gatorade®, lemon flavor, pH-3.0] as drinking water, in order to achieve dentin erosion and consequently dentin hypersensitivity. Rats of G3 were submitted to stress induction by restriction of movements and 1 h of shakes (New York subway stress). Stress evaluation was performed by the open field model. The body weight during treatments of all groups was taken weekly. After thirty days, all groups were submitted to the hypersensitivity test assessed by an air stimuli in the labial surface of molars, for 1 second and the rat’s response was scored as 0, 0.5, 2 or 3 grade. After euthanasia, jaws were removed and dental elements were observed in SEM.
Result: Rats of G2 showed higher scores of dentin hypersensitivity than G1 (p< 0.05) and G3 showed the highest scores compared with G1 and G2 (p< 0.001), confirming that the stress increased the pain response. Rats of G3 had body weight and locomotion frequency reduced compared with G1 (p< 0.05) and the immobility duration increased in both, G2 and G3 groups. No differences were observed between the rearing frequency and defecation. SEM of dental elements showed exposed tubules in G2 and G3.
Conclusion: The stress had an important role in dentin hypersensitivity in our animal model of erosion revealed by an increased response to stimuli air, a reduction in body weight and behavioral data.