Multiloop Edgewise Arch-wire Technique for Skeletal Class III Openbite: A Case Report

Dharma Laxmi Basukala

doi:10.3126/ojn.v7i2.20169

Abstract

Skeletal Class III with openbite is one of the most difficult malocclusion to treat orthodontically. Generally, the morphological characteristics of this malocclusion are poor antero-posterior growth of the maxilla or excessive growth of the mandible with high angle. An 18-year-old male had Class III malocclusion with retrognathic maxilla and normal mandible with high angle. All third molars except on fourth quadrant were extracted to eliminate the posterior crowding. Multiloop Edgewise Arch-wire (MEAW) technique was used to upright the mesially inclined buccal teeth and to correct occlusal plane. In nine month time, anterior cross bite and open bite were corrected; normal overjet, overbite and Class I canine relation were achieved.

Highlights

Skeletal Class III open bite is usually characterized by a high mandibular plane angle, obtuse gonial angle, overdeveloped mandible or underdeveloped maxilla, excessive vertical dimension of the upper molar, flattening of the occlusal plane, labial tipping of the maxillary anterior teeth, lingual tipping of the mandibular anterior teeth and a small cranial base angle
A developing Class III malocclusion may be considered an effect of the posterior discrepancy or posterior crowding which is related to the insufficient eruption space caused by the insufficient anterior-posterior diameter due to an increased vertical growth of the maxilla.[7]
Alignment and intrusion was started through a progressive tip back bend activation from the premolar teeth to the molar areas using a vertical elastic (3/16 inch, 6oz) in the anterior and short Class III elastics (3/16 inch, 6 oz) on left side (Figure 3-7)

Summary

INTRODUCTION

Skeletal Class III open bite is usually characterized by a high mandibular plane angle, obtuse gonial angle, overdeveloped mandible or underdeveloped maxilla, excessive vertical dimension of the upper molar, flattening of the occlusal plane, labial tipping of the maxillary anterior teeth, lingual tipping of the mandibular anterior teeth and a small cranial base angle. The posterior discrepancy is an important etiological factor in the development of a skeletal Class III malocclusion because it affects occlusal plane. The vertical position of posterior teeth in Class III malocclusion is not stable during growth and development.[2,3] Continuous molar eruption occurs during growth of the facial structure and during the post pubertal growth period.[4,5]. A developing Class III malocclusion may be considered an effect of the posterior discrepancy or posterior crowding which is related to the insufficient eruption space caused by the insufficient anterior-posterior diameter due to an increased vertical growth of the maxilla.[7]. This system typically includes the following changes: 1. The Posterior teeth were intruded and uprighted so that the occlusal plane could be reconstructed and the mandible repositioned posteriorly

Repositioning the mandible might prevent overgrowth of the condyle

DISCUSSION