Millett D T, Hallgren A, Cattanach D, McFadzean R, Pattison J, Robertson M, Love J
Unit of Orthodontics, Glasgow Dental Hospital and School, UK.
Angle Orthod. 1998 Aug;68(4):351-6. doi: 10.1043/0003-3219(1998)068<0351:AYCROB>2.3.CO;2.
The purpose of this study was to investigate the time to first failure of stainless steel orthodontic brackets (Ormco Corp, Glendora, Calif) bonded with a light-cured resin adhesive (Transbond, 3M Unitek, Monrovia, Calif) and assess whether time to failure was related to the patient's age at the start of treatment or sex, the proficiency of the individual placing the brackets, or the presenting malocclusion. Data on 548 patients with 7118 bonded brackets were analyzed. Survival analysis was carried out on a single bracket per patient. In each patient, the first bracket to fail was studied. In cases where no brackets failed, the bracket with the shortest follow-up time was analyzed and handled as a censored observation in the formal analysis. Median time until first bracket failure was 442 days, and an overall failure rate of 6% was recorded. There were no significant differences in time to first failure of brackets with respect to the sex or age of the patient at the start of treatment (p = 0.168, and p = 0.261, respectively), operator proficiency in placing brackets (p = 0.189), or presenting malocclusion (p = 0.052). Performance of brackets bonded with Transbond does not appear to vary significantly according to the variables examined.
本研究的目的是调查用光固化树脂粘合剂(Transbond,3M Unitek,加利福尼亚州蒙罗维亚)粘结的不锈钢正畸托槽(奥美科公司,加利福尼亚州格伦多拉)首次出现故障的时间,并评估故障时间是否与治疗开始时患者的年龄、性别、放置托槽者的熟练程度或初始错牙合有关。对548例患者的7118个粘结托槽的数据进行了分析。对每位患者的单个托槽进行生存分析。在每位患者中,研究第一个出现故障的托槽。在没有托槽出现故障的情况下,对随访时间最短的托槽进行分析,并在正式分析中作为删失观察值处理。首个托槽出现故障的中位时间为442天,记录的总体故障率为6%。托槽首次出现故障的时间在治疗开始时患者的性别或年龄(分别为p = 0.168和p = 0.261)、放置托槽者的熟练程度(p = 0.189)或初始错牙合(p = 0.052)方面没有显著差异。用Transbond粘结的托槽的性能似乎不会因所检查的变量而有显著差异。