A STUDY OF HOLOGRAPHIC INTERFEROMETRY ON THE INITIAL REACTION OF MAXILLOFACIAL COMPLEX TO THE INTERMAXILLARY FORCES ON THE ORTHODONTIC ARCHWIRES

교정용 호선에 악간 교정력 적용시 악안면골의 초기반응에 관한 Holographic Interferometry 연구

This study was performed to evaluate the initial reaction of maxillofacial complex to the Class II intermaxillary and the anterior vertical elastic forces on the six types of archwires including multiloop edgewise arch wires(MEAW). A human dry skull was used for this purpose and this investigation was done by holographic interferometry. Based on such investigation, the fringe pattern and the number of fringes of each condition were compared and analyzed. The findings of this study were as follows: 1. As the orthodontic forces increased, the amount of displacement increased. 2. As the orthodontic forces were applied, the fringes were shown not only in the teeth and the maxilla but also in the adjacent bones, i.e., temporal bone, zygomatic bone, nasal bone, frontal bone and sphenoid bone. And the direction of fringe pattern and the number of fringes were different from each other by the sutures. 3. As the long Class II elastic forces were applied, the backward-downward displacements of the anterior teeth and the maxilla were shown, and backward displacement of the former were grater than those of the latter. And backward displacements were greater by the long Class II elastic forces than by the short Class II elastic forces. 4. As the anterior vertical elastic forces were applied, downward displacements of the anterior teeth and the maxilla were shown, and the downward displacements of the former were greater than those of the latter relatively. 5. The downward displacements of the anterior area to the anterior vertical elastic forces of the MEAW were greater than those of other archwires. In addition, the more tip-back bend was applied, the more displacement was seen. 6. As the Class II intermaxillary forces and the enough anterior vertical elastic forces were applied on the MEAW with tip-back bend, there was an intrusive effect of the posterior teeth.