Injectable contraceptives are a valid option in every family planning program. Contraceptives which are administered every 2 or 3 months, containing only progestogen agents (DepoProvera, Noristerat) have proven efficacious and do not show long-term safety problems. They differ from other contraceptives in their long lasting action and by not presenting the contraindications of the estrogens. Their most prominent side-effect is the irregularity of cyclic bleeding. Although bleeding irregularities are not life threatening, many users stop the treatment for that reason. Monthly contraceptives comprising progestogens and estrogens, maintain or improve the high efficacy of the earlier forms and have the added benefit of allowing bleeding to resemble the physiologic one. This increases acceptability and the continuation rate. There is no long-term inconvenience. At this point, the greatest experience is with the formulation known as Topasel or Perlutal. Other formulations (Cyclofem, Mesigyna) are beginning to be commercialized and their characteristics must still be confirmed through daily use. Indications, contraindications, precautions and warnings for the use of monthly injectable contraceptives are basically identical to those of the combined oral contraceptives, as are the side-effects. Efficacy, though, proves to be superior, which can be correlated to a simpler method of use and less risk of error when using it. Main motivation factors are: efficacy, simplicity in usage, reversibility and confidentiality.
Orthodontic wires are made of alloys containing different metals, including nickel. It is important to evaluate their biocompatibility prior to use, owing to their long-term use in patients. This in vitro study compared the cytotoxicity and chemical composition of six latest orthodontic wires: Fantasia®, Tanzo®, FLI®, NT3®, DuoForce®, and Gummetal®. The before-use group consisted of wires that were not used in the mouth, and the after-use group consisted of wires that were used in the mouth for two months. The wires were placed in contact with human gingival fibroblasts (HGF) for 72 h, and cytotoxicity was determined using the resazurin test. The chemical composition and surface characterisation were evaluated by spectrometry and scanning electron microscopy. The groups were compared using ANOVA and Kruskal–Wallis test. Only the FLI® wires produced a 36% reduction in HGF viability (
p
<
0.05
) and presented greater irregularities and loss of polymer structure. After-use wires showed a significant reduction in the percentage of nickel and the appearance of new elements (oxygen and carbon). Therefore, it can be concluded that no toxic ion release was noticed in this study. Rhodium-coated wires were more stable than PTFE-coated wires, and only the FLI® wires showed a slight cytotoxic effect.
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