Littlewood S J, Millett D T, Doubleday B, Bearn D R, Worthington H V
Orthodontic Department, St Luke's Hospital, Little Horton Lane, Bradford, West Yorkshire, UK, BD5 0NA.
Cochrane Database Syst Rev. 2004(1):CD002283. doi: 10.1002/14651858.CD002283.pub2.
Retention is the phase of orthodontic treatment that attempts to keep teeth in the corrected positions after orthodontic (dental) braces. Without a phase of retention there is a tendency for the teeth to return to their initial position (relapse). To prevent relapse almost every patient who has orthodontic treatment will require some type of retention.
To evaluate the effectiveness of different retention strategies used to stabilise tooth position after orthodontic braces.
The Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE and EMBASE were searched. Several journals were handsearched. No language restrictions were applied. Authors of randomised controlled trials (RCTs) were identified and contacted to identify unpublished trials. Most recent search: December 2002.
RCTs on children and adults, who have had retainers fitted or adjunctive procedures undertaken, following orthodontic treatment with braces to prevent relapse. The outcomes are: how well the teeth are stabilised, survival of retainers, adverse effects on oral health and quality of life.
Screening of eligible studies, assessment of the methodological quality of the trials and data extraction were conducted in duplicate and independently by two reviewers. As no two studies compared the same retention strategies (interventions) it was not possible to combine the results of any studies.
Four trials satisfied the inclusion criteria. These trials all compared different interventions: circumferential supracrestal fiberotomy (CSF) combined with full-time removable retainer versus a full-time removable retainer alone; circumferential supracrestal fiberotomy (CSF) combined with a nights-only removable retainer versus a nights-only removable retainer alone; removable Hawley retainer versus a clear overlay retainer; and three types of fixed retainers versus a removable retainer. There was weak unreliable evidence, based on data from one trial, that there was a statistically significant increase in stability in both the mandibular (p < 0.001) and maxillary anterior segments (p < 0.001) when the CSF was used, compared with when it was not used. There was also weak, unreliable evidence that teeth settle quicker with a Hawley retainer than with a clear overlay retainer after 3 months. The quality of the trial reports was generally poor.
REVIEWER'S CONCLUSIONS: There are insufficient research data on which to base our clinical practice on retention at present. There is an urgent need for high quality randomised controlled trials in this crucial area of orthodontic practice.
保持是正畸治疗的一个阶段，旨在在使用正畸（牙齿）矫治器后使牙齿保持在矫正后的位置。如果没有保持阶段，牙齿有回到初始位置（复发）的趋势。为防止复发，几乎每个接受正畸治疗的患者都需要某种类型的保持。
评估用于稳定正畸矫治器治疗后牙齿位置的不同保持策略的有效性。
检索了Cochrane口腔健康小组试验注册库、CENTRAL、MEDLINE和EMBASE。对几本期刊进行了手工检索。未设语言限制。确定并联系了随机对照试验（RCT）的作者以识别未发表的试验。最近一次检索时间为2002年12月。
针对接受过正畸矫治器治疗以防止复发的儿童和成人进行的RCT，这些患者已佩戴保持器或进行了辅助程序。结局指标包括：牙齿稳定程度、保持器的留存情况、对口腔健康的不良影响以及生活质量。
两名评价员独立重复进行符合条件研究的筛选、试验方法学质量评估和数据提取。由于没有两项研究比较相同的保持策略（干预措施），因此无法合并任何研究的结果。
四项试验符合纳入标准。这些试验均比较了不同的干预措施：环周龈上纤维切断术（CSF）联合全日制可摘保持器与单纯全日制可摘保持器；环周龈上纤维切断术（CSF）联合仅夜间佩戴的可摘保持器与单纯仅夜间佩戴的可摘保持器；可摘霍利保持器与透明覆盖式保持器；以及三种类型的固定保持器与可摘保持器。根据一项试验的数据，有微弱且不可靠的证据表明，与未使用CSF相比，使用CSF时下颌（p < 0.001）和上颌前牙段（p < 0.001）的稳定性在统计学上有显著提高。也有微弱且不可靠的证据表明，3个月后使用霍利保持器时牙齿比使用透明覆盖式保持器时更快稳定。试验报告的质量总体较差。
目前没有足够的研究数据作为我们在保持阶段临床实践的依据。在正畸实践的这一关键领域迫切需要高质量的随机对照试验。
