Orthodontic Department, Leeds Dental Institute, Leeds, UK.
Orthodontic Department, St Luke's Hospital, Bradford, UK.
J Orthod. 2023 Mar;50(1):55-68. doi: 10.1177/14653125221118935. Epub 2022 Sep 4.
Bonded retainers are widely used to maintain the positions of anterior teeth after orthodontic treatment. Various types of bonded retainer exist however, there is a lack of evidence to indicate which type is superior.
To compare upper and lower CAD/CAM nitinol bonded retainers (Memotain) with upper and lower chairside rectangular-chain bonded retainers (Ortho-FlexTech™), in terms of stability, retainer failures and patient satisfaction.
Multi-centre, two-arm, parallel-group, randomised controlled clinical trial with 1:1 allocation.
Three trial centres: University Teaching Hospital; District General Hospital; and Specialist Orthodontic Practice. All treatment was provided free as part of a state-funded healthcare system.
A total of 68 patients were randomly allocated to receive either upper and lower Memotain bonded retainers or upper and lower Ortho-FlexTech™ bonded retainers. Ten trained operators placed and reviewed the bonded retainers. Measurements were carried out on study models taken at debond and after six months. Patient satisfaction questionnaires were completed at six months following debond.
The trial was terminated due to the high number of failures (50%) of the upper Memotain® retainers within six months. Memotain retainers were three times more likely to fail (unadjusted hazard ratio = 2.82, 95% confidence interval = 1.00-7.99) than Ortho-FlexTech™ retainers at six months in the upper arch. Patients were satisfied with both types of retainer.
Early termination of the trial means that the a priori sample size was not reached, so outcomes should be interpreted with caution.
The trial was terminated early due to the high failure rate of upper Memotain bonded retainers. They had a higher risk of failure in the maxillary arch when compared to upper Ortho-FlexTech™ bonded retainers after six months.
正畸治疗后，广泛使用粘结保持器来保持前牙的位置。然而，存在各种类型的粘结保持器，缺乏证据表明哪种类型更优。
比较上、下颌 CAD/CAM 镍钛诺粘结保持器（Memotain）与上、下颌椅旁矩形链粘结保持器（Ortho-FlexTech™）在上颌和下颌的稳定性、保持器失败和患者满意度方面的差异。
多中心、双臂、平行组、随机对照临床试验，采用 1:1 分配。
三个试验中心：大学教学医院；地区综合医院；和专科正畸诊所。所有治疗均作为国家资助的医疗保健系统的一部分免费提供。
共有 68 名患者被随机分配接受上、下颌 Memotain 粘结保持器或上、下颌 Ortho-FlexTech™粘结保持器。10 名经过培训的操作人员放置和检查粘结保持器。在脱粘时和脱粘后 6 个月时对研究模型进行测量。在脱粘后 6 个月时完成患者满意度问卷。
由于上 Memotain®保持器在 6 个月内失败率（50%）较高，试验提前终止。在上颌弓中，Memotain 保持器在 6 个月时失败的可能性是 Ortho-FlexTech™保持器的三倍（未调整的危险比=2.82，95%置信区间=1.00-7.99）。两种类型的保持器都得到了患者的满意。
试验提前终止意味着预先设定的样本量未达到，因此结果应谨慎解释。
由于上 Memotain 粘结保持器的高失败率，试验提前终止。与上 Ortho-FlexTech™粘结保持器相比，在上颌弓中，Memotain 粘结保持器在 6 个月后失败的风险更高。
