콘빔전산화단층촬영을 이용한 위턱골격확장장치를 위한 입천장 평가

Abstract

The maxillary skeletal expander (MSE) is the most recently developed device that is utilized for skeletal expansion by splitting the midpalatal suture by implanting the 4 miniscrews to the palate for Class Ⅲ malocclusion patients. In the previous researches, on the other hand, many researches have been focused on the midpalatal suture area and the anterior palate area behind the incisive foramen to determine the position and length of a single miniscrew to obtain adequate initial fixation and stable retention. Therefore, the purpose of this study was to measure the thickness of the palatal bone and the palatal soft tissue for miniscrew-supported maxillary skeletal expander using cone beam computed tomography images. This study were used high resolution cone beam computed tomography images in total of 58 men and women with Class Ⅲ malocclusion at Chosun University Dental Hospital. The thickness of the palatal bone and palatal soft tissue was measured at 3 mm intervals anterior-posteriorly based on the horizontal reference line connecting the central fossa of the maxillary first molar, and at 2 mm intervals medial-laterally based on the antero-posterior reference line connecting the anterior nasal spine and the posterior nasal spine. The difference of the obtained measurement values according to the left and right, the gender, and the measurement positions was statistically analyzed. The palatal bone thickness was statistically significant thicker in male than in female in the anterior palate up to the horizontal reference line, and the posterior palate was no significant difference in gender. The palatal soft tissue thickness was statistically significant thicker in male than female in all measurement positions. As the distance from the antero-posterior reference line increased, the palatal bone thickness decreased, while the palatal soft tissue thickness increased. In total thickness of the palate, male had significantly thicker at level 1, and the other Levels showed similar thickness. On the other hand, female did not show significant difference according to Level, but rather decreased at Level 2 and then increased toward Level 5. These findings could provide quantitative data on the thickness of the bone and soft tissue of the palate to determine the safe fixture length for miniscrew-supported maxillary skeletal expander.