Meta-analysis compares Herbst and Twin Block appliances for Class II malocclusion in growing patients

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Frontiers in Medicine Published May 16, 2026 Medically reviewed May 16, 2026 Study authors: Franz Tito Coronel-Zubiate, Joan Manuel Meza-Málaga, Sara Antonieta Luján-Valencia, Consuelo Marroqu… DOI ↗ By Dr. Sofia Müller, MD · Lifespan & Whole-Person Care

Key Takeaway

Consider that Herbst offers modest advantages in mentolabial angle and molar relationship over Twin Block, but patient factors guide choice.

This systematic review and meta-analysis included 7 randomized controlled trials with 548 growing patients (≤16 years) with Class II malocclusion. The review compared the Herbst appliance with the Twin Block appliance for skeletal, dental, and soft tissue effects.

Key findings from the meta-analysis showed that the Herbst appliance had a statistically significant advantage over the Twin Block for mentolabial angle (SMD 0.56; 95% CI: 0.15–0.96) and molar relationship (SMD -0.31; 95% CI: -0.56 to -0.05). Other outcomes were not reported with pooled effect sizes.

Limitations of the evidence include that adverse events, follow-up duration, and primary outcomes were not reported. The authors note that both appliances are effective, and the modest advantages of the Herbst should be weighed against patient-specific factors such as adherence, comfort, esthetics, and growth stage.

For clinicians, this meta-analysis provides comparative data but does not offer individual patient-level details. The findings support that both appliances are viable options, with Herbst showing slight benefits in specific cephalometric parameters. Clinical decisions should remain individualized.

Study Details

Study typeMeta analysis

EvidenceLevel 1

PublishedMay 2026

View Original Abstract ↓

Class II malocclusion is a common skeletal abnormality in growing patients, often associated with mandibular retrusion. Functional appliances such as Herbst and Twin Block appliances aim to stimulate mandibular growth during puberty. However, evidence comparing their effectiveness remains inconsistent. To compare the skeletal, dental, and soft tissue effects of Herbst and Twin Block appliances in growing patients with Class II malocclusion through a systematic review and meta-analysis. Randomized controlled trials (RCTs) comparing both appliances in children ≤16 years of age with Class II malocclusion were included if they reported skeletal, dental, or soft tissue outcomes. Non-randomized studies, case reports, reviews, and those with incomplete data were excluded. PubMed, Scopus, Web of Science, the Cochrane Library, and EMBASE, among other sources, were searched until January 30, 2025, with no language or date restrictions. Risk of bias was assessed using the Cochrane RoB 2.0 tool, and the certainty of the evidence was evaluated using the GRADE method. A random-effects meta-analysis calculated standardized mean differences (SMDs) with 95% confidence intervals. Seven RCTs with 548 participants were included. Both appliances effectively managed Class II malocclusion, with generally similar effects on skeletal and soft tissue parameters. The Herbst appliance showed significant advantages in improving the mentolabial angle (SMD: 0.56; 95% CI: 0.15–0.96) and molar relationship (SMD: −0.31; 95% CI: −0.56 to −0.05). No significant differences were observed in other outcomes. Both the Herbst and Twin Block appliances are effective for Class II correction in growing patients. The Herbst appliance offers modest advantages in certain parameters, but clinical decisions should also consider patient-specific factors such as adherence, comfort, esthetics, and growth stage. https://www.crd.york.ac.uk/PROSPERO/view/CRD420251011083, PROSPERO: CRD420251011083.