Assuntos
Bis-Fenol A-Glicidil Metacrilato , Polimetil Metacrilato , Polimetil Metacrilato , Resinas Compostas , Resinas Compostas , Lâmpadas de Polimerização Dentária , Materiais Dentários , Materiais Dentários , Adesivos Dentinários , Adesivos Dentinários , Dureza , Metacrilatos , Processos Fotoquímicos , Polímeros , Ácidos Polimetacrílicos , Ácidos Polimetacrílicos , Poliuretanos , Poliuretanos , Autocura de Resinas Dentárias , Estresse Mecânico , Propriedades de Superfície , Fatores de TempoRESUMO
This in vitro study assessed the effect of an experimental 4% TiF(4) varnish compared to commercial NaF and NaF/CaF(2) varnishes and 4% TiF(4) solution on enamel erosion. For this, 72 bovine enamel specimens were randomly allocated to the following treatments: NaF varnish(2.26% F), NaF/CaF(2) varnish (5.63% F), 4% TiF(4) varnish (2.45% F), F-free placebo varnish, 4% TiF(4 )solution (2.45% F) and control (not treated). The varnishes were applied in a thin layer and removed after 6 h. The solution was applied to the enamel surface for 1 min. Then, the specimens were alternately de- and remineralized (6 times/day) in an artificial mouth for 5 days at 37 degrees C. Demineralization was performed with the beverage Sprite (1 min, 3 ml/min) and remineralization with artificial saliva (day: 59 min, 0.5 ml/min; during the night: 0.1 ml/min). The mean daily increment of erosion and the cumulative erosion data were tested using ANOVA and ANCOVA, respectively, followed by Tukey's test (alpha = 0.05). The mean daily erosion increments and cumulative erosion (micrometers) were significantly less for the TiF(4) varnish (0.30 +/- 0.11/0.65 +/- 0.75) than for the NaF varnish (0.58 +/- 0.11/1.47 +/- 1.07) or the NaF/CaF(2) varnish (0.62 +/- 0.10/1.68 +/- 1.17), which in turn showed significantly less erosion than the placebo varnish (0.78 +/- 0.12/2.05 +/- 1.43), TiF(4) solution (0.86 +/- 0.11/ 2.05 +/- 1.49) and control (0.77 +/- 0.16/2.06 +/- 1.49). In conclusion, the TiF(4) varnish seems to be a promising treatment to reduce enamel loss under mild erosive conditions.
Assuntos
Esmalte Dentário/efeitos dos fármacos , Fluoretos Tópicos/uso terapêutico , Selantes de Fossas e Fissuras/química , Erosão Dentária/prevenção & controle , Análise de Variância , Animais , Bebidas Gaseificadas , Cariostáticos/administração & dosagem , Cariostáticos/química , Cariostáticos/uso terapêutico , Bovinos , Fluoretos Tópicos/administração & dosagem , Fluoretos Tópicos/química , Dureza , Selantes de Fossas e Fissuras/uso terapêutico , Distribuição Aleatória , Saliva/fisiologia , Fluoreto de Sódio/administração & dosagem , Fluoreto de Sódio/química , Estatísticas não Paramétricas , Titânio/administração & dosagem , Titânio/química , Desmineralização do Dente/induzido quimicamente , Remineralização DentáriaRESUMO
This in situ/ex vivo study assessed the effect of different concentrations of fluoride in dentifrices on dentin subjected to erosion or to erosion plus abrasion. Ten volunteers took part in this crossover and double-blind study performed in 3 phases (7 days). They wore acrylic palatal appliances containing 4 bovine dentin blocks divided in two rows: erosion and erosion plus abrasion. The blocks were subjected to erosion by immersion ex vivo in a cola drink (60 s, pH 2.6) 4 times daily. During this step, the volunteers brushed their teeth with one of three dentifrices D (5,000 ppm F, NaF, silica); C (1,100 ppm F, NaF, silica) and placebo (22 ppm F, silica). Then, the respective dentifrice slurry (1:3) was dripped on dentin surfaces. While no further treatment was performed in one row, the other row was brushed using an electric toothbrush for 30 s ex vivo. The appliances were replaced in the mouth and the volunteers rinsed with water. Dentin loss was determined by profilometry and analyzed by 2-way ANOVA/Bonferroni test (a = 0.05). Dentin loss after erosive-abrasive wear was significantly greater than after erosion alone. Wear was significantly higher for the placebo than for the D and C dentifrices, which were not significantly different from each other. It can be concluded that the presence of fluoride concentrations around 1,100 ppm in dentifrices is important to reduce dentin wear by erosion and erosion + abrasion, but the protective effect does not increase with fluoride concentration.