Objective: To compare the treatment effectiveness of temporary anchorage devices and transpalatal arch through the method of meta-analysis.
Methods: Following the guidelines and checklist provided by contemporary PRISMA, electronic database including PubMed, Cochrane library and Science Direct were used for paper searching. Papers that included in this study are randomized controlled trials. Expert opinions, case reports, case series, review articles, clinical trials without controls, controlled clinical trials were excluded in this study. Scientific paper searching in this study covered the period 1997 to December 2015 by suing the keywords mini-screw, mini-implant, temporary anchorage devices (TADs), transpalatal arch (TPA) and conventional anchorage. There are two reviewers execute the searching strategy, Cohen's kappa coefficient was used for measurement of the inter-rater agreement. Any disagreement was resolve by the first author. Review Manager (Version 5.3; Cochrane Collaboration, Oxford, England) was used for meta-analysis.
Results: There are 2 randomized controlled trials met the inclusion criteria. The meta-analysis showed that after the anterior retraction, the horizontal and vertical measurement of upper incisor change significantly in TPA (mean difference, U1-X: -2.04; U1-Y: -0.56 under 95% CI) and TADs group (mean difference, U1-X: -3.00; U1-Y: -2.79 under 95% CI), as well as nasolabial angle (mean difference, TPA: 4.36; TADs: 0.23 under 95% CI) and upper lip to E-line (mean difference, TPA: -0.14 95%; TADs: -1.43 under 95% CI).
Conclusions: Temporary anchorage devices give a better result for anterior retraction in terms of upper incisor and soft tissue changes.