比较口内扫描和模型扫描对数字化牙列模型咬合定量分析的影响  

Influence of intraoral scan and dental cast scan on occlusal quantitative analysis of virtual dental model

作　　者：程明轩 姜婷[1] 孙玉春[1,2] 张皓羽 CHENG Ming-xuan;JIANG Ting;SUN Yu-chun;ZHANG Hao-yu(Department of Prosthodontics, Peking University School and Hospital of Stomatology ＆ National Engineering Laboratory for Digital and Material Technology of Stomatology ＆ Beijing Key Laboratory of Digital Stomatology, Beijing 100081, Chi-na;Center of Digital Dentistry, Peking University School and Hospital of Stomatology, Beijing 100081 , China)

机构地区：[1]北京大学口腔医学院.口腔医院修复科口腔数字化医疗技术和材料国家工程实验室口腔数字医学北京市重点实验室,北京100081 [2]北京大学口腔医学院.口腔医院口腔医学计算机应用中心,北京100081

出　　处：《北京大学学报（医学版）》2018年第1期136-140,共5页Journal of Peking University:Health Sciences

基　　金：北京市科技计划课题首都特色临床应用及普及项目(Z171100001017096);北京大学口腔医院临床新技术新疗法项目(PKUSSNCT-16A01)资助~~

摘　　要：目的:为了更准确地进行上下颌牙列数字化模型的咬合状况定量分析,对分别用口内扫描和模型扫描方法获取的三维数字化模型的咬合接触指标进行定量分析及对比研究。方法:用三维激光扫描仪对具有完整牙列并且咬合正常的健康志愿者5人进行口内扫描,分别获取单侧1个牙位(第一磨牙)、2个牙位(第二前磨牙及第一磨牙)、3个牙位(两个前磨牙及第一磨牙)及其邻牙的上下颌数字化模型,运用专用计算机分析软件进行牙尖交错位时咬合接触状况的三维测量及分析,然后用加成型硅橡胶采取上下颌牙列实物印模并灌制超硬石膏模型,应用专用定位装置将上下颌模型在牙尖交错位对合并固定,用激光扫描仪扫描上下颌模型,形成三维数字化牙列模型。对用口内和模型扫描方法分别获得的数字化模型的下颌第一磨牙进行咬合接触紧密程度(上下颌咬合面平均间距)、咬合接触面积及牙尖斜度等咬合相关指标的定量分析和比较。应用配对t检验方法比较两种扫描方法获得数字化模型的各项指标的统计学差异(α=0.05),重复测量计算牙尖斜度的组内相关系数(intraclass correlation coefficient,ICC)进行一致性检验。结果:口内扫描1~3个牙位时获得的上下颌第一磨牙咬合面平均间距分别比模型扫描的小0.134 mm、0.177 mm和0.207 mm,差异有统计学意义(P<0.5)。两种扫描方法的标准差之差分别为0.02 mm、0.02 mm和0.03 mm,差距较小。口内扫描1~3个牙位时下颌第一磨牙的咬合接触面积分别比模型扫描的大8.65 mm^2、10.28 mm^2和11.46 mm^2,差异有统计学意义(P<0.5)。两种扫描方法的标准差之差为0.43 mm^2、1.55 mm^2和2.04 mm^2,1个牙位扫描后的标准差要明显小于2个牙位和3个牙位时。两种扫描方法进行牙尖斜度测量时,ICC大于0.90,两种方法的牙尖斜度测量值差异无统计学意义(P>0.5)。结论:口内扫描测得的咬合面平Objective ： To make more accurate occlusal quantitative analysis o f three-dimensional （3D ） virtual dental models and to compare the occlusal contact obtained by in tra ora l and dental cast scan. Methods： In this study, 5 subjects were in tra ora l scanned using laser scanner （3 shapes, Germany） to obtain the 3D virtual models of one tooth （ the f irs t mo la r） , two teeth （ th e second premolar and the f irs t molar） , three teeth （the premolars and the f irs t mo la r） and th e ir opposite te e th, respect ively. The s i l i-cone impressions were made and dental stone models were poured fo r each o f them. The dental casts were scanned and then they were f ixed to the maximum intercuspal position w i th a special locating j ig fo r a res-canning of occlusal posit ion. The v ir tual models taken in tra o ra l ly and obtained w ith dental cast scan were introduced to a 3D quantitative analysis system, and some c r ite r ia regarding to occlusal contact were c a l-culated and analyzed. The occlusal c r ite r ia were mean values o f occlusal clearance space between the u p-per and lower occlusal surface （clearance） , occlusal contact area （area） , and cusp in c l in a t io n （angle） of the mandibular first molar. Paired t tests were used to evaluate differences o f occlusal c r ite r ia between the virtual models obtained wi th the in tra ora l scan and dental cast scan （ 〇： = 0.05 ）. Results ： The mean values of occlusal clearance of one to three teeth obtained by way o f in tra ora l scan were smal ler than those obtained by way of cast scan by 0. 134 mm , 0. 177 mm , and 0. 207 m m , respect ively. W h i le the oc c lu-sal contact areas were greater than the cast scan by 8. 65 mm2 , 10. 28 mm2 , and 11.46 mm2. No s tat ist i-cally significant differences were found between the cusps in c l in a t io n s obtained w ith the two scanning methods, and the interc

关 键 词：成像 三维 激光 牙 图像处理 计算机辅助 牙科印模技术 

分 类 号：R783[医药卫生—口腔医学]