Korean J Orthod.  1986 Mar;16(1):71-84.

A photoelastic analysis of the effect of orthopedic forces on the craniofacial complex utilizing the three kinds of the head gear

• Kim KH

Abstract

The purpose of this study was to analyze the effect of orthopedic forces on the craniofacial complex utilizing the three kinds of the head gear (high pull head gear, straight pull head gear, cervical pull head gear) For this study, the teeth and alveolar bone and palate were reproduced from birefringent materials and other parts of craniofacial complex were coated with birefringent material on the model. The effect of orthopedic forces on the craniofacial complex was analyzed by photoelastic method using transmission polariscope and reflection polariscope. The results were as follows 1. The cervical pull head gear had the greatest tipping effect on the maxillary molars and high pull head gear had the least tipping effect 2. In areas stressed, the cervical pull head gear stressed the greatest degree 3. Only cervical pull head gear produced stress at the zygomaticofrontal suture and the posterior region of palate 4. The straight pull head gear and high pull head gear produced stress at just inferior to the anterior nasal spine 5. The cervical pull head gear and straight pull head gear produced tensile stress at the frontomaxillary suture 6. The pterygoid plates of the sphenoid bone, the zygomatic arches, the junction of the maxilla with the lacrimal and ethmoid bone, and the maxillary molars were affected by three types of head gear.

MeSH Terms

Ethmoid Bone
Head*
Maxilla
Molar
Orthopedics*
Palate
Sphenoid Bone
Spine
Sutures
Tooth
Zygoma