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Correlation of twin-block appliance efficacy and wear duration as assessed with a compliance indicator

Nikita R Baheti1, Wasundhara A Bhad1, Santosh J Chavan1

  • 1Department of Orthodontics and Dentofacial Orthopedics, Government Dental College and Hospital, Nagpur, India.

Journal of the World Federation of Orthodontists
|December 24, 2021
PubMed

Insights

Full-time wear of twin block (TB) appliances significantly enhances skeletal changes in orthodontic treatment. Part-time wear shows less pronounced skeletal effects but comparable dental improvements over six months.

Area of Science:

  • Orthodontics
  • Dentofacial Orthopedics
  • Biomedical Engineering

Background:

  • Orthodontic treatment efficacy is influenced by patient compliance.
  • Twin block (TB) appliances are commonly used for correcting malocclusions.
  • Objective measurement of appliance wear time is crucial for assessing treatment outcomes.

Purpose of the Study:

  • To investigate the association between objective wear time and treatment efficacy of twin block (TB) appliances.
  • To compare skeletal and dentoalveolar changes in patients with full-time versus part-time TB appliance wear.

Main Methods:

  • A compliance indicator was used to objectively measure wear time in 44 children (11-14 years) using TB appliances.
  • Participants were categorized into full-time (FT >17 h/d) and part-time (PT < 12 h/d) wear groups.
  • Cephalometric and study model analyses were performed at baseline and after 6 months.

Main Results:

  • Full-time wear (mean 20.86 h/d) resulted in a significantly greater reduction in the ANB angle (2.69°) and increase in mandibular base (Pg/OLp: 2.22mm) compared to part-time wear (mean 9.55 h/d).
  • Overjet reduction was statistically significant in both groups, with greater reduction in the FT group (3.91 mm vs. 2.0 mm).
  • Skeletal effects were more pronounced with full-time wear, while dentoalveolar changes were comparable between groups.

Conclusions:

  • Maximum skeletal treatment effects of twin block appliances are achieved with full-time wear.
  • Objective wear time is a critical determinant of TB appliance efficacy, particularly for skeletal changes.
  • Orthodontic treatment planning should emphasize patient compliance for optimal outcomes.
Abstract

Keywords:
ComplianceTwin block applianceWear time

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