上颌前磨牙非龋性颈部缺损修复的有限元研究  

Restoration of non-carious cervical lesions in the first maxillary premolar:a three dimentional finite element study

作　　者：皇甫若奇[1] 徐晓[1] 

机构地区：[1]上海交通大学医学院附属第九人民医院·口腔医学院口腔特诊科,上海市口腔医学重点实验室,上海200011

出　　处：《上海口腔医学》2011年第1期26-30,共5页Shanghai Journal of Stomatology

基　　金：上海科学技术委员会资助项目(08DZ2271100)~~

摘　　要：目的:探讨充填治疗非龋性颈部缺损时,洞型设计、窝洞深度及充填材料和咬合调整因素的影响。方法:构建成人上颌第一前磨牙三维有限元模型,其颊侧颈部有不同洞型(楔形、矩形和弧形)和窝洞深度(0.5mm、1.0mm和1.5mm),模拟用玻璃离子黏固剂(GIC)、复合树脂和银汞合金充填,计算模型在正常的侧向、垂直向加载及创伤的侧向、垂直向加载时,应力值和应力分布。结果:正常颊侧颈部主要为拉应力,近根尖向出现压应力,应力分布较均匀;创伤时主要也为拉应力但应力集中,且较正常产生更大的应力。2种咬合状态在侧向加载都比垂直向产生更大应力和加重应力集中。不同窝洞深度间应力差异小,但有深度加深、应力变大的正相关性。深度0.5mm、1.0mm的楔形、弧形和矩形洞型差异小。但在1.5mm时,矩形洞型产生的应力远大于楔形(约4倍),楔形洞型应力略大于弧形(0.8～4.1MPa)。相同条件下,银汞合金充填体界面应力值大于GIC和复合树脂(3～9倍),GIC小于复合树脂(0.2～2.4MPa)。结论:窝洞较浅时,洞型不是影响治疗的首要因素,窝洞较深则应避免矩形洞型。PURPOSE： To investigate the influences of factors such as cavity depth,shape,restorative materials and occlusal adjustment on the restoration of non-carious cervical lesions（NCCL） in the first maxillary premolars.METHODS： 3-D finite element models of adult first maxillary premolars which had cavities of different depths and shapes in buccal cervical region were built.The models were restored and divided into three groups： glass ion cement（GIC）,amalgam and composite resin.The stress profiles and distribution in normal occlusion and malocclusion were evaluated from vertical to lateral loading.RESULTS： In normal occlusion,there was mainly tensile stress and uniform distribution on the buccal cervical margin,compressive stress appeared when approaching to tooth root;in malocclusion,there was mainly greater concentrated tensile stress on the buccal cervical margin than normal occlusion.In all the two occlusions,lateral loading increased stress concentration and value comparing with vertical loading.The contrast between different cavity depths showed significant positive correlation between stress value of restoration and cavity depth.The wedge,rectangle and rounded shaped cavity in the cases of small cavities depths（0.5,1.0mm） exhibited no difference.For larger cavity depth（1.5mm）,the stress of rectangular cavity was greater than the wedge（about 4 times）,but no difference between the wedge and the rounded.The interface stress value of GIC and composite resin model was smaller than that of amalgam,the latter was 3-9 times greater than the former two.The GIC was slightly smaller than the resin（0.2-2.4 MPa）.CONCLUSIONS： For small cavity depth,cavity shape is not the primary factor affecting the treatment of NCCL.The rectangular cavity isn＇t suitable for large defect.There is positive correlation between stress value of restoration and cavity depth.

关 键 词：非龋性颈部缺损 三维有限元法 充填体 洞型 应力分布 

分 类 号：R783[医药卫生—口腔医学]