全瓷冠断裂失效行为的断口形貌分析  

Fractographic analysis on fracture failure behavior of all-ceramic crowns

作　　者：鲍新莲 苏怡 Bao Xinlian;Su Yi(Department of Stomatology,Eye&ENT Hospital of Fudan University,Shanghai 200031,China)

机构地区：[1]复旦大学附属眼耳鼻喉科医院口腔科,上海市200031

出　　处：《中国组织工程研究》2021年第28期4504-4509,共6页Chinese Journal of Tissue Engineering Research

摘　　要：背景:近年来,断口形貌分析法被应用于陶瓷的断裂力学研究,目前研究多集中在利用断口形貌学的典型裂纹特征分析临床折断全瓷冠的裂纹源和扩展路径,以及全瓷冠在体外模拟状态下的循环疲劳损伤模式分析。目的:应用断口表面形貌学分析全瓷冠失效的裂纹起始源和有关缺陷。方法:选择2018年10月至2019年9月在复旦大学附属眼耳鼻喉科医院口腔科就诊的患者,共12例临床使用失效后的全瓷冠折裂片,采用立体显微镜观察全瓷折裂片断面整体形貌,采用扫描电子显微镜观察裂纹形态、表面破坏、结构缺陷等,通过断口表面形貌特征分析,推断裂纹起源和扩展路径。试验获得复旦大学附属眼耳鼻喉科医院伦理委员会批准。结果与结论:①循环疲劳是全瓷修复体折裂的重要原因,12例全瓷冠断裂片可以观察到不同类型的循环疲劳损伤模式,比如锥状裂纹、饰瓷崩瓷、饰核瓷分离、放射状裂纹、结构缺陷等,不同的全瓷冠占主导的疲劳损伤模式不同;②循环疲劳损伤是全瓷冠失效的重要原因,其中放射状裂纹是主要模式,瓷层的厚度及核瓷与饰瓷的厚度比值密切影响它的产生;饰瓷-核瓷界面是双层全瓷修复体的薄弱环节,结构缺陷和异常咬合导致的应力集中是全瓷冠失效的潜在危险因素。BACKGROUND:In recent years,fractographic analysis has been applied to the study of fracture mechanics of ceramics.At present,most studies focus on the analysis of crack origin and propagation path of clinical fracture of all-ceramic crowns by using the typical crack characteristics of fractographic analysis,as well as the analysis of cyclic fatigue damage mode of all-ceramic crowns in vitro simulation state.OBJECTIVE:The fractographic analysis was used to analyze the crack origin and related defects of all-ceramic crowns.METHODS:From October 2018 to September 2019,a total of 12 patients with all-ceramic crowns fracture after failure in clinical use were selected from the Department of Stomatology,Eye&ENT Hospital of Fudan University.The stereomicroscope was used to observe the overall morphology of all-ceramic fracture section.The scanning electron microscope was used to observe the crack,surface damage and structural defects.The origin and propagation path of crack were deduced by the fractographic analysis.This trial was approved by the Ethics Committee of Eye&ENT Hospital of Fudan University.RESULTS AND CONCLUSION:(1)Cyclic fatigue was an important reason for the fracture of all-ceramic restorations.Different types of cyclic fatigue damage modes could be observed in 12 fractured pieces of all-ceramic crowns,such as cone crack,veneer chipping,veneer delamination,radial crack,and surface defects.Different all-ceramic crowns had different dominant fatigue damage modes.(2)Cyclic fatigue damage was an important reason for the failure of allceramic crowns,among which radial crack was the main mode.The thickness of porcelain layer and core/veneer thickness ratio have a close influence on its occurrence.The interface between veneer and core is the weak link of double-layer all-ceramic restorations.Structural defects and stress concentration caused by abnormal occlusion are potential risk factors for failure of all-ceramic crowns.

关 键 词：材料 口腔 全瓷冠 牙科陶瓷 临床失效 裂纹 断口形貌 

分 类 号：R459.9[医药卫生—治疗学] R318.08[医药卫生—临床医学]