含氟正畸陶瓷托槽长期氟释放性能的研究

A long-term study of fluoride release of the modificated ceramic orthodontic bracket

目的研发具有氟释放性能的正畸陶瓷托槽,体外条件下验证其长期氟释放的能力。方法左上颌中切牙陶瓷托槽15个(3M公司美国):在托槽底板的牙侧用牙科高速手机制备一空腔。使用两种材料(磷酸锌水门汀+NaF、磷酸锌水门汀+CaF2)充填于腔内,然后在托槽底板上涂一层粘结剂(FujiORTHO LC或TransbondTMXT)。利用离子液相色谱检测样本在去离子水中24 h释放出的氟离子浓度。实验第1周每天测试,此后的2个月每周测试一次(于测试前24 h更换去离子水),以后改为每月测试1次,持续9个月共315天。结果虽然陶瓷托槽底板涂布了粘结剂,无论粘结剂本身是否含氟都没有阻止改良托槽的氟释放,而且起到了缓释的作用。结论改良陶瓷托槽中以NaF为充填材料以RMG IC为粘接剂组的氟释放量最多;粘结剂的涂布没有阻止所填材料的氟释放,且起到了缓释作用。

Objective To manufacture a novel modification ceramic bracket and test its ability of fluoride-releasing in vitro. Methods Two materials, a zinc phosphate ＋ NaF, a zinc phosphate ＋ CaF2, were used to modify fifteen brackets. Fluoride release was measured daily during the first week and then weekly for 8 weeks, monthly for 9 months. Results the RMGIC ＋ NaF group and RMGIC group released more fluride during the first two weeks, then decreased rapidly, The NaF ＋ TransbondTMXT group and the NaF ＋ Transbond^TM XT group released lower and consistent fluride during the test. Conclusions The use of paset （with or without fluoride） did not completely prevent the continued fluoride releasing of the ceramic brackets. It is possible to modify an orthodontic bracket to give it the ability to release fluoride over a period of fixed appliance treatment.