【作者】 杨峰；

【导师】 莫三心；

【作者基本信息】 郑州大学 ， 口腔修复学， 2005， 硕士

【摘要】 目的 采用临床上常用的几种粘结剂研究牙体预备抛光前后金属全冠固位力的变化。探讨抛光对不同种粘结材料提供的粘结力、微机械固位力的大小、比例的影响。 材料与方法 选取收集到的牙体完整、未经治疗的因正畸拔除的前磨牙60颗,并将牙齿随机分成六组,每组10个。用高速涡轮机金刚砂车针在喷水降温下进行牙体制备,预备完成后形成6×4×3mm~3的立方体,其中三组预备体不做抛光形成一表面粗糙的粘结表面。另外三组采用橡皮轮抛光。常规制作铸造全冠。将抛光的三组和未抛光的三组分别用磷酸锌(ZOP)、玻璃离子(GIC)和树脂(CR)粘结铸造全冠。在生理盐水中经5℃±2℃和50℃±2℃冷热循环实验。用材料力学试验机,拉伸速度为10mm/min,记录试件拉断时的破坏载荷值。 抛光前后全冠粘结力的测定:去除全冠约束的影响,将全冠粘结转化为平面粘结,以测定粘结力。首先,制备与全冠组织面理化性状相同的金属平面。其次,在牙冠轴面用金钢砂车针预备3×6mm~2牙本质平面,分别用磷酸锌、玻璃离子和树脂将牙本质与金属平面粘结,在生理盐水中经:5℃±2℃和50℃±2℃冷热循环实验。用材料力学试验机,拉伸速度为10mm/min,记录试件拉断时的破坏载荷值。得出单位面积的固位力大小,进而计算出全冠轴面粘结力的大小。将(牙合)更多还原

【Abstract】 Objective: To evaluate the different strength of bonding and mechanical interlocking of three kinds of luting cements and explore their relating effects by means of observing the change of retention strength of metal full crowns pre- and-post polishing.Material and methods: Freshly extracted human premolars were collected, cleaned and randomly separated into six groups, and prepared teeth with air turbine diamonds points in the condition of water-cooling. A cube of 6×4×3mm~3 was made after such preparation, besides three groups were polished with rubber and the other three groups were not polished, and then made a metal crown for each sample, afterwards three kinds of luting cements Zinc phosphate cement (ZOP), glass ionomer cement(GIC),and resin cement (RC) were selected to bond the metal full crowns to the samples of each group. After thermal cycling between 5℃± 2℃ and 50℃± 2℃ for a total of 1500 cycles and with the speed of 10mm/min in the material mechanics machine the retention strength was performed.Apart from the effect of binding, the effect of bonding was tested. A metal cube of 10 × 10×2 mm~3 was made firstly. Reducing proximal into a plane of 3 × 6mm2.Then felt the plane to the cube with the three kind of luting cements . After thermal cycling between 5℃± 2℃ and 50℃± 2 ℃ for a total of 1500 cycles the bond strength was performed. The occlusion bond strength was performed in the same way. Calculate the mechanical interlocking strength by the expressions bellow: mechanical interlocking strength equal retention strength minor occlusion bond strength and axis bond strength.Statistical analysis was performed with the program SPSS. Results:The retention strength, mechanical interlocking strength and bond strength of ZOP group decreased after polishing , The statistical analysis showed that there has significant difference. There has no obvious change of retention strength of GIC group and RC group. The mechanical interlocking strength is lower and bond strength is higher after polishing of GIC group. There has no obvious change of mechanical interlocking strength and bond strength of RC group. Conclusions:The retention capacities of the complete crowns from the highest to least were: CR > GIC>ZOP. The effects varied with different cements in the retention of complete metal crowns because of the discrepancy in bonding and mechanical interlocking properties.Mechanical interlocking plays a prominent role when ZOP or GIC is used, and the role of bonding is apparent in RC. Polishing has a high effect on ZOP and little affect on GIC and RC.更多还原