Effect of removable and fixed retainer on periodontal status and retention effect: a Meta-analysis
ZHANG Yao
LI Jiao
ZHAO Yun-he
LEI Lang
Abstract：Objective To investigate the effect of removable retainers (Hawley and Vacuum-formed retainer) and fixed retainers on periodontal status and the retention effect.Methods Seven databases were searched including Pubmed,Cochrane Library and CNKI,which were updated until March 1st,2017.Two researchers finished the screenings,data extraction and bias risk evaluation separately.RevMan 5.2 software was utilized to finish the data processing and statistical analysis.Results Totally 20 researches were included in the study and 18 was used in Meta-analysis.For periodontal status Hawley demonstrated better results when compared with vacuum-formed retainer [gingival index (GI):MD =0.11,95％ CI 0.05 ～ 0.16,P ＜ 0.05;plaque index (PLI):MD =0.11,95％ CI 0.07 ～0.16,P ＜ 0.05],and Hawley also showed advantages over fixed retainer (GI:MD =0.23,95％ CI 0.14～0.32,P ＜ 0.05;PLI:MD =0.37,95％ CI 0.25 ～ 0.48,P ＜ 0.05;calculus index (CI):MD =0.52,95％CI 0.21 ～ 0.83,P =0.001);whereas no differences were found between fixed and vacumm-formed retainer.For retention effect,vacuum-formed retainer displayed more benefits than Hawley retainers (Little index:MD =-0.41,95％CI-0.51 ～-0.30,P ＜ 0.05).Conclusion Hawley shows benefits in periodontal status in a short term when compared to vacuum-formed and fixed retainers,while vacuum-formed retainer shows advantages in retaining the treatment result over Hawley retainers.Larger-sample and randomized long-term studies are needed to acchieve more reliable results.
Keywords：relapseremovable retainerfixed retainer
Publication Date：2017-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：8( 724-731 )