Effects of Class II activator and Class II activator high-pull headgear combination on the mandible: A 3-dimensional finite element stress analysis study


ULUSOY M. Ç. , Darendeliler N.

AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS, vol.133, no.4, 2008 (Journal Indexed in SCI) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 133 Issue: 4
  • Publication Date: 2008
  • Doi Number: 10.1016/j.ajodo.2007.10.032
  • Title of Journal : AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS

Abstract

Introduction: The aim of this study was to evaluate the effects of the Class II activator and the Class II activator high-pull headgear (HG) combination on the mandible with 3-dimensional (3D) finite element stress analysis. Methods: A 3D finite element model of the mandible was constructed from a dry human mandible. To investigate the effects of the Class II activator, a 3D model of the lower part of this appliance was constructed and fixed on the mandibular model. The Class II activator high-pull headgear model was established as described, and an extraoral traction force of 350 g was directed from the middle of the Class II activator to the top of the mandibular condyle. The stress regions were studied with the finite element method. Results: The regions near the muscle attachment areas were affected the most. The inner part of the coronoid process and the gonial area had the maximum stress values. Conclusions: Both functional appliances can cause morphologic changes on the mandible by activating the masticatory muscles to change the growth direction.