三维图像融合技术评价上颌全牙列种植固定修复前后的鼻唇软组织形态变化

目的:探讨利用面部与义齿三维(three dimensional,3D)图像融合方法评估全牙列种植固定修复前后鼻唇区软组织形态变化的可行性。方法:选择于北京大学口腔医院种植科就诊的上颌无牙颌患者共12例(女性4例、男性8例),平均年龄(54.82±5.50)岁(45~62岁)。于上颌植入4~6枚种植体,6个月后为患者佩戴全牙列固定义齿,捕捉患者佩戴义齿前后的3D面相及义齿形态数据。将三维数据置于同一坐标系中,对义齿和软组织标志点进行测量,分别比较各标志点左口角点(cheilion left, CHL)、右口角点(cheilion right, CHR)、左唇峰点(crista philtri left,CPHL)、右唇峰点(crista philtri right, CPHR)、上唇缘点(labrale superius, LS)、鼻下点(subnasale, SN)、口裂正中点(stomion,STO)、上中切牙点(upper incisor, UI)、义齿上边缘顶点(F-point, F)]的位移量及标志点间线距人中长度(SN-LS)、双唇峰间距(CPHR-CPHL)、口裂宽(CHR-CHL)、上唇红高度(LS-STO)]变化。结果:义齿与软组织拟合后,义齿上边缘顶点与鼻下点直线距离(F-SN)三次测量结果的一致性检验显示该方法可重复性好,组内相关系数(intraclass correlation coefficient, ICC)为0.983 (95%CI:0.957~0.995)。佩戴义齿后,软组织各标志点均发生前徙变化,鼻底区域变化最小,SN前后方向上的位移为(0.61±0.44) mm,LS前后向位移为(3.12±1.38) mm。在垂直方向上,SN、LS、CPHL、CPHR均向上移动,STO、CHL、CHR向下方少量移动。除SN-LS略微减小外,CHR-CHL、CPHR-CPHL、LS-STO均增大(P<0.01)。SN与F、LS与UI的Z轴坐标值均呈现高度相关(r=0.904 3、r=0.958 4)。结论:三维面像与义齿图像融合方法可重复性好,经该方法检测,义齿与软组织标志点的前后向位移之间存在高度相关性。

Validation of the digital integration technology for evaluating the nasolabial morphology variation after the cross-arch fixed restoration of maxillary implant-supported prostheses

Objective: To explore the applicability of integration between three-dimensional (3D) facial and dental data to evaluate the nasolabial morphology variation before and after the cross-arch fixed restoration of the maxillary implant-supported prostheses. Methods: Twelve patients (4 women and 8 men), mean age (54.82±5.50) years (from 45 to 62 years) referred to the Department of Oral Implan-tology, Peking University School and Hospital of Stomatology, were selected and diagnosed with edentulous maxilla. For all the patients, 4 to 6 implants were inserted into the maxilla. Six months later, the final cross-arch fixed prostheses were delivered. The 3D facial images were collected before and after the final restoration. The 3D data of prostheses were also captured. All the 3D data were registered and measured in the same coordinate system. Then the displacement of all the landmarks cheilion left (CHL), cheilion right (CHR), crista philtri left (CPHL), crista philtri right (CPHR), labrale supe-rius (LS), subnasale (SN), stomion (STO), upper incisor (UI), upper flange border of the prostheses (F-point, F)], and the variation of the distances between these landmarks (SN-LS, CPHR-CPHL, CHR-CHL, LS-STO) were analyzed and compared. Results: The consistency test among three measurements of the length of F-SN indicated that the integration method of the dental prostheses and soft tissue had the good repetitiveness, ICC=0.983 (95%CI: 0.957-0.995). After wearing the final cross-arch maxillary implant-supported prostheses, all the landmarks on the soft tissue moved forward. The nasal base area changed minimally, and the shift of SN in the sagittal direction was only (0.61±0.44) mm. But the sagittal shift of LS was (3.12±1.38) mm. In the vertical direction, SN, LS, CPHL, and CPHR moved upward. But STO, CHL, and CHR moved downward a little. Except for the slight decrease of the length of philtrum (SN-LS), the length of CHL-CHR, CPHL-CPHR, and the height of upper lip were increased together (P<0.01). In the direction of Z axis, the strong correlations were found not only between the movements of SN and F (r=0.904 3) but also between the movements of LS and UI (r=0.958 4). Conclusion: The integration method of 3D facial and dental data showed good repetitiveness. And the strong correlations between the landmarks of prostheses and nasolabial soft tissue in the sagittal direction were found by this new method.