In vitro reduction of dental erosion by low-concentration TiF₄ Solutions

The aims of this study were to compare daily versus single applications of low-concentration TiF₄ solutions for reduction of enamel erosion and to evaluate the enamel surface loss due to application of these solutions. Sixty bovine enamel samples were randomly divided into 2 groups: single versus daily treatment with TiF₄ solution (ST vs. DT), which were subdivided into 5 subgroups (n = 6): 0% (control); 0.1, 0.5, 0.75 and 1% TiF₄ concentration. Fluoride treatment was performed by immersing specimens in 10 ml of the TiF₄ solutions for 5 min and rinsing them with tap water for 30 s. ST specimens were treated once only, DT specimens were treated before each erosion cycle. All specimens were subjected to 4 erosion cycles: 6 immersions of 2 min in Sprite, tap water rinse for 1 min and storage in artificial saliva for 1.5 h. Erosive enamel loss was measured using light profilometry, after each fluoride treatment and each erosive cycle. The values of surface loss/gain at application of the TiF₄ solutions did not significantly differ from zero. At the end of the 4 erosion cycles, 0.5% showed the least (ST: 3.45 ± 0.27 μm, DT: 1.08 ± 1.69 μm) and 1% showed the most surface loss (ST: 4.87 ± 1.13 μm, DT: 6.56 ± 1.49 μm). A significant reduction of surface loss was found only for 0.5% DT (p = 0.009). Within the limitations of an in vitro study, it was concluded that multiple applications of a 0.5% TiF₄ solution significantly reduced enamel erosion in vitro and caused no enamel loss at application.