RESUMO
Abstract Objective This study aimed to evaluate the effects of different toothpastes on the surface wear of enamel, dentin, composite resin (CR), and resin-modified glass ionomer cement (RMGIC), and to perform a topographic analysis of the surfaces, based on representative images generated by atomic force microscopy (AFM) after erosion-abrasion cycles. Methodology One hundred and forty bovine incisors were collected and divided into two groups: 72 enamel and 72 dentin blocks (4×4 mm). Half of the specimens were restored with CR (Filtek Z350 XT) and the other half with RMGIC (Fuji II LC). Then, samples were submitted to a demineralization cycle (5 days, 4×2 min/day, 1% citric acid, pH 3.2) and exposed to three different toothpastes (2×15 s/day): without fluoride (WF, n=12), sodium fluoride-based (NaF, n=12), and stannous fluoride-based (SnF2, n=12). Surface wear, as well as restoration interfaces wear, were investigated by profilometry of the dental substrates and restorative materials. All representative surfaces underwent AFM analysis. Data were analyzed by two-way analysis of variance and Tukey's tests (α=0.05). Results NaF-based toothpaste caused the greater dentin surface wear (p<0.05). Toothpastes affected only enamel-restoration interfaces. AFM analysis showed precipitate formation in dentinal tubules caused by the use of fluoride toothpastes. Conclusions NaF-based toothpastes had no protective effect on enamel adjacent to CR and RMGIC against erosion-abrasion challenges, nor on dentin adjacent to RMGIC material. SnF2-based toothpastes caused more damage to interfaces between enamel and RMGIC.
Assuntos
Animais , Bovinos , Erosão Dentária/induzido quimicamente , Erosão Dentária/prevenção & controle , Cremes Dentais , Resinas Compostas , Cimentos de Ionômeros de Vidro , Esmalte Dentário , DentinaRESUMO
All over the world fixed orthodontic cases face a common problem –enamel hypoplasia that is white spot lesion. It can be remineralised by brushing with fluoridated toothpaste, fluoride mouth rinses and topical application of fluoride gel/foam. Efficiency of remineralisation is enhanced with daily usage of 0.05%(225ppm) sodium fluoride or 0.2% (900ppm) weekly; or with 0.4%Stannous Fluoride gel. But Stannous Fluoride stains the enamel. Enamel can also be remineralised with casein phosphopeptide-amorphous calcium phosphate(CCP-ACP). Remineralised white spot lesion can be bleached to mask the colour and can be microabraded followed by bleaching leaving a highly polished surface with calcium phosphate packed into the interprismatic enamel surface area.
RESUMO
El propósito de la presente investigación fue evaluar el comportamiento biocinético de la 99mTc-ciprofloxacina obtenida de una nueva formulación. Un ensayo in vitro y un modelo de infección experimental demostraron su afinidad por bacterias vivas. La vida media en sangre fue de 5,89 +/- 0,85 horas. La biodistribución mostró alta acumulación en músculos infectados y baja en tejidos sanos.
The aim of the present investigation was to evaluate the biokinetics performance of 99mTc-ciprofloxacin obtained from a new formulation. Both in vitro assays and experimental infection models demonstrated its affinity for viable bacteria.Half life in blood was 5.89 +/- 0.85 hours. The biodistribution showed high accumulation on infected muscles and low on healthy tissues.