A FINITE ELEMENT ANALYSIS OF THE STRESS DISTRIBUTION AND DISPLACEMENT IN HUMAN MAXILLA TO RAPID PALATAL EXPANSION

상악골 급속 확장시 상악골의 응력 분산과 변위에 대한 유한요소법적 분석

Recently, rapid palatal expansion technique is widely used for the correction of the skeletal imbalance in Cl III malocclusion patients. There were many studies about the cephalometric changes to rapid palatal expansion but quantitative analysis were small. The purpose of this study was to analysis the stresses and displacement of the maxilla in human dry skull to rapid palatal expansion. The results were as follows: 1. The anterior portion of palate show more lateral and inferior displacement than the posterior portion. But the posterior portion show more anterior displacement. 2. In transpalatal suture area, the medial portion show more anterior and inferior displacement than the lateral portion. But the lateral portion show more lateral displacement than the medial portion. 3. In mid-sagittal plane, the lower portion (palatal area) of maxilla show more anterior, lateral, inferior displacement than the upper portion (frontamaxillary stuture area). 4. In zygomatic arch, the adjacent area to maxilla show tonsil. stresses and the adjacent area to frontal bone show compressive stresses. 5. The sequence of stress bearing area to R.P.E. is upper retromolar area, upper 1st molar, 1st premolar, 2nd premolar, anterior segment of teeth.