Surgery · Medical Literature
Comparative Evaluation of Microimplant and Traditional Anchorage in Class II Malocclusion Therapy: A Systematic Review and Meta-Analysis.
Abstract
Class II malocclusion affects aesthetics and function. Traditional anchorage methods have limitations, and microimplant anchorage (MIA) requires thorough comparison. The objective of this study was to compare the efficacy of MIA with traditional anchorage in treating patients with Class II malocclusion through meta-analysis. This study used a systematic review and meta-analysis, searching 5 English-language and 4 Chinese-language databases. The research question was structured using the PICO framework: Population (Class II malocclusion patients), Intervention (MIA), Comparison (traditional anchorage), and Outcome (cephalometric angle changes). A search formula was created using subject terms and Boolean logic. The Cochrane tool assessed bias risk in randomized controlled trials (RCTs), and the Newcastle-Ottawa scale evaluated the quality of nonrandomized studies. Evidence levels were assessed with GRADE. This study focused on indicators with clinical significance such as the sella-nasion (SN)-A point angle (SNA°). RevMan 5.4 software calculated the standardized mean difference (SMD) and odds ratio, with heterogeneity assessed using I2 and publication bias evaluated using funnel plots and Egger test, along with subgroup and sensitivity analyses. A total of 11 studies were included in the systematic review, of which 2 were RCTs and 9 were retrospective or controlled studies. Meta-analysis incorporated the data from all 11 studies, revealing that the MIA group showed a greater change in nasolabial angle than the traditional anchorage group (SMD = 0.58, P < .001) but no significant differences in SNA°, SN-B point angle, upper incisor to SN plane angle, A point-nasion-B point angle or SN plane to mandibular plane angle. The change in nasolabial angle before and after treatment was less minor in the MIA group for patients with Class II malocclusion. This provides evidence-based guidance on selecting treatment methods for patients with Angle's Class II malocclusion in clinical practice. Previous studies have shown that the choice of anchorage affects the orthodontic effect of Class II malocclusion. This meta-analysis found that the microimplant anchorage technique has certain advantages in treating patients with Angle's Class II malocclusion compared with the traditional anchorage approach; however, the degree of maxillary alveolar bone remodeling warrants further discussion.
Clinical relevance
In patients with Class II malocclusion, does microimplant anchorage (MIA) produce superior cephalometric outcomes compared with traditional anchorage methods? __SNAPSHOT__ {"studyDesign":"Systematic review and meta-analysis (incorporating randomized controlled trials and non-randomized studies)","setting":"Multi-database literature search; 5 English-language and 4 Chinese-language databases searched; specific countries or institution types of included studies not reported in available abstract","sampleSize":"Not reported (total number of included studies and pooled participants not available from abstract; abstract appears truncated)","population":"Patients diagnosed with Class II malocclusion; specific age ranges, skeletal vs. dental subclassification proportions, and inclusion/exclusion criteria beyond PICO framework not reported in available abstract","intervention":"Microimplant anchorage (MIA) — temporary skeletal anchorage devices (e.g., miniscrews) used to provide orthodontic anchorage during Class II correction","comparator":"Traditional anchorage methods (specific devices — e.g., headgear, transpalatal arch, J-hook — not individually delineated in available abstract)","primaryOutcome":"Cephalometric angle changes with clinical significance, including the sella-nasion to A-point angle (SNA°) as a key indicator; additional cephalometric endpoints referenced but not fully enumerated in available abstract","followUp":"Not reported","fundingSource":"Not reported"}
Key findings
The abstract as provided is truncated and does not include the quantitative results of the meta-analysis. Specifically, no standardized mean differences (SMDs), odds ratios, 95% confidence intervals, p-values, I² heterogeneity statistics, or funnel plot conclusions are available for reporting. The abstract confirms that RevMan 5.4 was used to calculate SMD and odds ratio, and that I² was used to assess heterogeneity and funnel plots were used to evaluate publication bias, but no numerical outputs from these analyses are present in the available text. No NNT or NNH can be calculated. No adverse event data are reported in the available abstract. All quantitative findings are therefore listed as not reported.
Practice implications
IMPORTANT LIMITATION: Only a truncated abstract is available for this summary; the abstract ends mid-sentence before reporting any results. No conclusions about the direction, magnitude, or statistical significance of MIA versus traditional anchorage can be drawn from the available text. The study is methodologically positioned as a rigorous synthesis — employing the PICO framework, Cochrane Risk of Bias tool for RCTs, Newcastle-Ottawa Scale for non-randomized studies, and GRADE evidence assessment — which, if the full analysis is internally consistent, could yield meaningful comparative evidence. The focus on SNA° as a primary cephalometric indicator captures maxillary skeletal position, which is clinically relevant to Class II correction. However, SNA° is a surrogate outcome; its relationship to patient-centered outcomes (aesthetics, functional occlusion, stability, quality of life) is not addressed in the available abstract. The inclusion of both Chinese- and English-language databases strengthens comprehensiveness but also introduces potential heterogeneity from differing study populations, traditional anchorage device types, and treatment protocols. Until the full publication is accessible and results are reviewed, no changes to clinical practice can be justified on the basis of this abstract alone. __LIMITATIONS__ 1. Abstract truncation: The abstract is cut off before presenting any results or conclusions, making it impossible to evaluate the actual findings, their magnitude, direction, or certainty. 2. Surrogate endpoints: SNA° and other cephalometric angles are surrogate measures; no data on patient-reported outcomes, long-term stability, or functional occlusion are mentioned. 3. Study design heterogeneity: Pooling RCTs with non-randomized studies using different quality tools (Cochrane vs. Newcastle-Ottawa) introduces methodological heterogeneity that may limit interpretability of combined SMDs. 4. Traditional anchorage heterogeneity: 'Traditional anchorage' is not a uniform comparator — headgear, transpalatal arches, J-hooks, and intermaxillary elastics have distinct biomechanical properties; pooling these without subgroup analysis may obscure meaningful differences. 5. Language and publication bias: Despite inclusion of Chinese-language databases, restriction to 9 databases and published literature may introduce publication bias, especially for null or negative results. 6. Generalizability: Inclusion of Chinese-language studies suggests a predominantly East Asian patient population, which may limit applicability to other ethnic or skeletal morphology profiles. 7. Funding and conflict of interest: Not reported, precluding assessment of sponsorship bias. 8. Follow-up: Duration of follow-up and post-treatment stability are not addressed in the available abstract. __BOTTOM_LINE_CATEGORY__ low_certainty __BOTTOM_LINE__ This systematic review and meta-analysis by Wu, Ren, Jiang et al. (2026) was designed to compare cephalometric outcomes of microimplant anchorage versus traditional anchorage in Class II malocclusion using rigorous methodology including GRADE evidence assessment, but the abstract is truncated before any quantitative results are presented. No practice-relevant conclusions can be drawn from the currently available text, and clinicians should await access to the full publication before considering any modification to anchorage strategy based on this review.