洞形深度对髓腔固位冠边缘和内部适合性影响的体外研究  

Effect of cavity depths on the marginal and internal discrepancy of endocrowns in vitro

作　　者：曾百进[1] 王婷婷 韩建民[2] 李媛[2] 林红[2] 高虹[1] 江青松[1] 

机构地区：[1]首都医科大学附属北京口腔医院修复科,北京100050 [2]北京大学口腔医学院、口腔医院口腔材料研究室,北京100081

出　　处：《口腔颌面修复学杂志》2018年第1期39-43,共5页Chinese Journal of Prosthodontics

基　　金：首都医科大学基础-临床合作项目(项目编号:17JL42);北京市科技计划-首都市民健康项目培育项目(项目编号:Z171100000417034)

摘　　要：目的:了解不同洞形深度对应用椅旁CAD/CAM制作的髓腔固位冠(endocrown)边缘和内部适合性的影响,以期为临床牙体预备提供参考。方法:制作三个不同深度相同聚合度的髓腔固位冠基准模型,并分别复制出12个超硬石膏模型,采用Cerec AC Bluecam扫描获取光学模型并制作修复体,粘结后,包埋、切割,利用三维测量系统测量髓腔固位冠边缘及内部粘接剂厚度并进行统计学分析。结果:三种洞形深度的髓腔固位冠边缘的粘接剂厚度均小于120μm,内部粘接剂的厚度均小于200μm;在边缘,3种洞形深度粘接剂的厚度两两比较差异均具有统计学意义(P<0.05);在轴牙合角处,粘接剂的厚度随着洞形深度的增加而增加,洞形深度为2mm和4mm时粘接剂的厚度差异具有统计学意义(P<0.05);在轴髓角处,洞形深度为3mm时与洞形深度为2mm和4mm时粘接剂厚度比较差异分别具有统计学意义(P<0.05);在牙合面肩台中点、轴壁和髓腔固位洞形底部,3种洞形深度粘接剂厚度两两比较差异均不具有统计学意义。除轴牙合角、轴壁和髓腔固位洞形底部,其他测量位点洞形深度为3mm时粘接剂的厚度最小。结论:基于本研究结果,应用椅旁CAD/CAM技术制作髓腔固位冠时,3种洞形深度的髓腔固位冠其边缘和内部适合性均能达到临床要求;洞形深度为3mm时其边缘和内部适合性优于深度为2mm和4mm时。Objective： To evaluate the effect of depths on the marginal and internal discrepancy of endocrowns fabricated with a chairside CAD/CAM system, and provide reference for clinical preparation. Methods： Three basic endocrowns with same convergence and different cavity depth were made. Impressions of each endocrowns were taken and poured with die-stone. Digital information was obtained with Cerec AC Bluecam from the models and the protheses were fabricated. After cemented to their corresponding models, the protheses were embedded with self-cure resin and cut with low speed cutting machine. Smartscrope MVP 2000 was used to measure the thickness of adhesive between prothesis and the die. Results： The thickness of adhesives at marginal site of endocrowns with three cavity depths was all smaller than 120μm, and that of internal site was all smaller than 200μm. At the marginal site, there was a significant difference between depth-2 mm, depth-3 mm and depth-4 mm when compared in pairs （P〈0.05）. Thickness increased with the cavity depth increasing at the axial-occlusal site, and significant difference was found between depth-2mm and depth-4mm （P〈0.05）. At the axial-pulpal site, depth-3mm had a statistically significant difference when compared to depth-2mm and depth-4mm respectively （P〈0.05）. Significant differences were not found at the middle of occlusal shoulder, axial, and pulpal sites. Depth-3mm had the smallest thickness than depth-2mm and depth-4mm at all the investigated sites except at axial-occlusal, axial and pulpal sites. Conclusions： With the results of the present study, the marginal and internal discrepancy of endocrowns which were fabricated with a chairside CAD/CAM system with the cavity depths of 2mm, 3mm and 4mm could all meet the clinical requirements, however, depth with 3mm may be more favorable.

关 键 词：髓腔固位冠 适合性 深度 

分 类 号：R783.1[医药卫生—口腔医学]