A comparative study of Twin-Block and van Beek Headgear-Activator on the three-dimensional morphology of the upper airway in growing children with mandibular retraction in skeletal class II malocclusion

Clin Oral Investig. 2024 Dec 27;29(1):31. doi: 10.1007/s00784-024-06066-7.

Abstract

Objectives: To compare the variations in the upper airway of children with skeletal Class II mandibular retrognathism treated with van Beek Headgear-Activator (vBHGA) and Twin-Block (TB) appliances.

Materials and methods: 40 children were involved in this retrospective study and divided into two intervention groups: the vBHGA group and the TB group, each comprising 20 individuals with an average age of 11.13 years. Employing Cone Beam Computed Tomography and Geometric Morphometric analysis, a comprehensive assessment of the upper airway's volume, minimum cross-sectional area (m-CSA), and 3D shape characteristics was conducted pre-and post-treatment.

Results: The total volume, oropharynx volume, oropharynx m-CSA, and hypopharynx m-CSA significantly increased in both the vBHGA and TB groups (p < 0.05). The sole discrepancy between the two groups was observed in comparing the nasopharynx m-CSA (p < 0.05). A morphological difference was observed in the vBHGA group before and after treatment (p < 0.05), characterized by a wider and shorter airway, positioning of the posterior nasal spine closer to the anterior inferior area, and a more posterior nasopharyngeal wall. However, there were no significant shape differences between the two groups or before and after treatment within the TB group.

Conclusion: It appears that both vBHGA and TB interventions contribute positively to alleviating upper airway constriction. Nonetheless, the vBHGA group exhibits more alterations in the configuration of the nasopharynx.

Clinical relevance: Both orthodontic appliances have a positive impact on the upper airway but still have differences, emphasizing the need for individualized consideration when selecting orthodontic interventions.

Clinical trial registration: This study was also registered with the Chinese Clinical Trial Registry with registration number ChiCTR2400086867.

Keywords: Three-dimensional morphology; Twin-Block; Upper airway; van Beek Headgear-Activator.

Publication types

  • Comparative Study

MeSH terms

  • Activator Appliances
  • Adolescent
  • Child
  • Cone-Beam Computed Tomography*
  • Extraoral Traction Appliances
  • Female
  • Humans
  • Imaging, Three-Dimensional* / methods
  • Male
  • Malocclusion, Angle Class II* / diagnostic imaging
  • Malocclusion, Angle Class II* / therapy
  • Orthodontic Appliance Design
  • Pharynx / diagnostic imaging
  • Retrognathia / diagnostic imaging
  • Retrognathia / therapy
  • Retrospective Studies
  • Treatment Outcome

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