连接体处基牙不同肩台宽度对全锆固定桥强度的影响

发布时间：2018-04-24 17:45

本文选题：全锆固定桥 + 连接体　；参考：《河北医科大学》2017年硕士论文

【摘要】：目的:本实验旨在采用牙科计算机辅助设计和计算机辅助制作(computer aided design and computer aided manufacture,CAD/CAM)工艺技术,制作后牙三单位全锆固定桥,研究全锆固定桥连接体处基牙不同肩台宽度对固定桥强度的影响,通过实验数据对临床全锆固定桥牙体预备及修复体制作提供参考。方法:1底座及基牙的制作通过对标准下颌模型的底座以及基牙进行设计,参考《口腔修复学》教材中固定义齿的基牙预备原则进行牙体预备。选取模型中右下第一磨牙缺失,右下第二前磨牙和第二磨牙为基牙的三单位全锆固定桥设计。基牙的牙体预备标准为:面均匀磨除1.5mm,轴面磨除1.0mm,轴面聚合度为8°,刃状或平龈内线角圆钝的直角肩台,各部位无倒凹、无应力集中区。根据实验设计右下第二前磨牙肩台宽度为1.0mm,右下第二磨牙肩台宽度分别为刃状、0.5mm、1.0mm。2金属代型制作将设计好的底座以及基牙预备体利用加成硅橡胶印模材制备印模,选择专用的铸造蜡以1:1的比例制作底座及基牙预备体蜡型,按标准流程包埋、铸造、打磨、喷砂完成金属代型的制作。3修复体的制作将金属底座以及基牙代型利用加成硅橡胶模仿牙周膜组合之后,用橡皮泥固定在扫描仪观测台上,用3Shape TRIOS 2光学印模扫描出预备体的3D数字化模型,随即将数据导入到3shape Dental System软件,系统会生成标准形态的修复体。根据第三版《口腔解剖生理学》关于右下颌第二前磨牙、第一磨牙和第二磨牙形态的描述,利用虚拟调刀修整至实验所需基牙面厚度为1.5mm,轴壁厚度为1.0mm,连接体横截面积为16mm2的近矩形截面,连接体龈以及颊舌外展隙为“U”型,曲率半径均为0.90mm,冠边缘处与金属代型的肩台平滑相接。即全锆固定桥右下第二前磨牙的肩台宽度为1.0mm,右下第二磨牙的肩台宽度分别为刃状、0.5mm、1.0mm,然后把所得到的数据传递给cam切割机。采用赛瓷系列氧化锆加工18个全锆固定桥。具体分组:右下第二磨牙的肩台宽度刃状、0.5mm、1.0mm各6个,分别定为a、b、c组。4抗压缩破坏力实验将制作完成的全锆固定桥用dmg树脂水门汀分别粘固于金属代型上,指压就位,以50n的垂直力持续加压10分钟,去除多余的粘固剂,在37℃蒸馏水存储24小时后备用。将粘结好的全锆固定桥按顺序依次置于万能试验机上进行强度测试,加载头以0.5mm/min的恒定速度垂直加载于金属垫衬垫硅橡胶缓冲材料的桥体上,直至全锆固定桥破坏为止,记录数值。5统计学分析使用spss21.0软件对实验数据进行统计学分析。kolmogorov-smirnov和shapiro-wilk检验数据是否符合正态分布(ɑ=0.1)。levene检验对数据进行方差齐性检验(ɑ=0.1)。在本次实验数据均满足正态分布及方差齐性检验(p0.1),实验数据可以用均数?标准差表示(sx?)。用单因素方差分析比较不同肩台宽度全锆固定桥的抗压缩破坏力有无组间差别,若组间有差别再用student-newman-keuls进行组间的两两比较。p0.05认为有统计学意义。6全锆固定桥样本断裂分析利用高速摄像机和数码光学显微镜对所有的18例全锆固定桥样本进行断裂分析。结果:1各组全锆固定桥的抗压缩破坏力值a组(刃状肩台):(4457.33?564.06)n;b组(0.5mm肩台):(6439.65?551.32)n;c组(1.0mm肩台):(6513.00?609.38)n。2统计学分析实验数据各组实验数据均符合正态分布及方差齐性,对各组全锆固定桥的抗压缩破坏力实验数据进行单因素方差分析:各组间的抗压缩破坏力有统计学意义(P0.05),即组间存在差异。进行组间的两两比较,A组与B组、A组与C组之间差异有统计学意义(P0.05);而B组与C组之间差异无统计学意义(P0.05)。3样本观察利用高速摄像机和数码光学显微镜对所有的18例全锆固定桥样本进行断裂分析。所有全锆固定桥的实验样本均为远中连接体处的斜型折裂。A组与B组的断裂均越过固位体边缘的外缘和内缘,表现为累及固位体组织面的断裂,裂纹起源于固位体边缘的拉应力集中区,通过连接体,然后向加载点扩展延伸至断裂破坏;C组的断裂表现为越过固位体边缘外缘,未越过其内缘,故未累及固位体组织面,裂纹源于连接体龈端的拉应力集中区,通过连接体,然后向加载点扩展延伸至断裂破坏。结论:1全锆固定桥连接体处基牙肩台宽度为0.5mm和1.0mm的强度显著优于刃状肩台的强度,而宽度为0.5mm和1.0mm的强度无统计学差异,建议临床全锆固定桥基牙肩台宽度预备在0.5mm以上,才能提高其强度。2全锆固定桥连接体处基牙肩台宽度为刃状和0.5mm的断裂形式与1.0mm肩台的断裂形式不同。肩台宽度为刃状和0.5mm的全锆固定桥断裂均越过固位体边缘的外缘和内缘,表现为累及固位体组织面的断裂,肩台宽度为1.0mm的全锆固定桥断裂越过固位体边缘外缘,未越过其内缘,表现为未累及固位体组织面的断裂。
[Abstract]:Objective: the purpose of this experiment was to make a three unit zirconium fixed bridge with computer aided design and computer aided manufacture, CAD/CAM technology and study the influence of different shoulder width of the base teeth on the strength of the fixed bridge. Provide reference for the preparation and repair of the clinical full zirconium fixed bridge. Methods: 1 base and base teeth are made by designing the base of the standard mandibular model and the base teeth, and referring to the basic tooth preparation principle of the fixed denture in the textbook of Stomatology. The right lower first molar is missing and the right lower two front grinding is selected. The teeth and the second molar were the three unit zirconium fixed bridge for the base teeth. The standard of tooth preparation for the base teeth was the uniform grinding of the 1.5mm, the axis surface grinding out of 1.0mm, the axial surface polymerization degree of 8 degrees, the edge of the edge or the inner corner of the gingiva, without the concave and stress concentration areas. The shoulder width of the two front molar of the right lower part was 1.0mm, The shoulder width of the right lower two molar is divided into the edge, 0.5mm, 1.0mm.2 metal generation, making the designed base and the base tooth preparation by adding the silicone rubber impression material to make the impression. The special casting wax is selected to make the base and the base tooth preparation wax type in the proportion of 1:1, and the metal generation is completed according to the standard process, casting, grinding and sandblasting. After making the.3 repair body, the metal base and the base tooth generation using the addition of silicon rubber imitated the periodontal membrane combination, with the rubber mud fixed on the scanner observation platform, the 3D digital model of the preparatory body is scanned with the 3Shape TRIOS 2 optical impression, then the data is imported into the 3shape Dental System software, the system will generate the standard form. According to the description of the shape of the right mandibular second premolar, the first molar and the second molar, according to the third edition of the oral anatomy and physiology, the thickness of the base tooth is 1.5mm, the thickness of the axial wall is 1.0mm, the transverse section of the connecting body is 16mm2, and the joint gingiva and the abduction gap of the buccal tongue are " U "type, the radius of curvature is 0.90mm, and the edge of the crown is smooth with the shoulder of metal generation. That is, the shoulder width of the two premolar of the right lower two molar of the total zirconium fixed bridge is 1.0mm, the shoulder width of the right lower two molar is edged, 0.5mm, 1.0mm, and then the obtained data is passed to the cam cutting machine. 18 zirconium zirconium is processed with Zr series. Fixed bridge. Specific groups: the shoulder width edge of the right lower two molar, 0.5mm, 1.0mm each 6, respectively, a, B, C group.4 compression failure experiment will be made of the completed zirconium fixed bridge DMG resin cement paste on the metal generation respectively, the finger pressure is in place, the vertical force of 50N for 10 minutes, remove the superfluous cement, at 37 degrees C The distilled water is stored for 24 hours after storage. The strength of the fixed zirconium fixed bridge is placed on the universal test machine in sequence, and the load head is loaded on the bridge body of the silicone rubber cushion material of the metal pad at a constant speed of 0.5mm/min until the total zirconium fixed bridge is damaged to stop, and the record value.5 statistics analysis uses spss21.0. Whether the.Kolmogorov-smirnov and Shapiro-Wilk test data are consistent with the normal distribution (=0.1).Levene test for the variance homogeneity test of the data (=0.1). The experimental data all meet the normal distribution and variance homogeneity test (P0.1), and the experimental data can be expressed by the mean? Standard deviation (SX?). The single factor analysis of variance compared with the different shoulder and platform width of the Zr fixed bridge, there is no difference between groups, if there is a difference between the groups with the difference of Student-Newman-Keuls between the 22 and.P0.05, there is a statistically significant difference between.6 and Zr fixed bridge sample fracture analysis using high speed image machine and digital optical microscope for all 18 cases Total zirconium fixed bridge samples for fracture analysis. Results: 1 group A (4457.33? 564.06) n; group B (0.5mm shoulder): (6439.65? 551.32) n; group C (1.0mm shoulder): (6513? 609.38): (6513? 609.38) statistical analysis of the experimental data all conforms to normal distribution and homogeneity of variance, to each group A single factor variance analysis of the experimental data of the anti compression failure force of the zirconium fixed bridge: there was significant difference in the anti compression destructive force between each group (P0.05), that is, the difference between groups was 22, the difference between group A and B, the difference between group A and C group was statistically significant (P0.05), but there was no statistically significant difference between group B and C group (P0.05).3 sample All 18 samples of all zirconium fixed bridge were analyzed by high speed camera and digital optical microscope. All the experimental samples of all zirconia fixed bridges were that the fracture of the oblique fracture.A group and the B group across the far middle connection crossed the outer and inner edge of the edge of the solid body. The tensile stress concentration region originating from the edge of the retainer, through the connecting body, and then extending to the fracture failure by extending to the loading point, the fracture of the C group is over the outer edge of the solid body edge, which does not cross the inner edge of the solid body, so the fracture is not involved in the retainer's tissue surface. The crack originates from the tension stress concentration area of the gingival end of the connecting body, and then extends to the loading point through the connection body. Conclusion: 1 the strength of the abutment width of 0.5mm and 1.0mm is significantly better than that of the blade abutment, while the strength of the width of 0.5mm and 1.0mm is not statistically different. It is suggested that the width of the abutment abutment of the clinical all zirconium fixed bridge foundation is more than 0.5mm to improve the strength of its strength.2 all zirconium fixed bridge connection. The fracture form of the width of the abutment with the width of the abutment and the 0.5mm is different from that of the 1.0mm shoulder. The fracture of the full zirconium fixed bridge with the width of the shoulder and the 0.5mm is all over the outer edge and the inner edge of the retainer edge, which shows the fracture of the retainer, and the whole zirconium fixed bridge with the width of the shoulder width is 1.0mm over the edge of the solid body. It did not exceed its inner edge, but it did not involve the fracture of retainer tissue surface.

【学位授予单位】：河北医科大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TP391.7;R783

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