3种树脂牙耐磨性和硬度的研究

Comparative study on the wear resistance and hardness of three types of resin teeth

目的研究3种不同种类树脂牙耐磨性和硬度的差异,为临床选牙提供理论依据和指导。方法采用球-盘式磨耗实验机对3种树脂牙,即传统型合成树脂牙(拜耳牙,A组)、交联加强型合成树脂牙(Excellence IPN牙,B组)和复合树脂牙(Endura塑钢牙,C组)进行三体磨耗实验,3D形貌扫描仪测量磨耗后体积和高度丧失量,扫描电镜观察磨耗后表面形貌,维氏显微硬度计测量树脂牙硬度。结果 3种树脂牙磨耗后体积和高度丧失量均为A>B>C,其中C组(0.42mm^3、45.50μm)与A组(0.85mm^3、70.04μm)、C组与B组(0.68mm^3、60.65μm)之间的差异均有统计学意义(P<0.05),而A组与B组之间没有统计学差异(P>0.05)。维氏硬度值分别为A组:19.40HV、B组:23.36HV、C组:29.00HV,三组间均有显著性差异(P<0.01)。C组显示出了最低磨耗量和最大硬度值。3种树脂牙体积和高度丧失量与硬度之间均呈负相关关系。结论 3种树脂牙的耐磨性和硬度均不同,复合树脂牙耐磨性能较好,IPN型交联合成树脂牙相比传统合成树脂牙,其耐磨性有所改善,树脂牙的硬度越高,耐磨性越好。

Objective To provide a theoretic foundation for the choosing of the resin teeth in clinic by evaluating and comparing the wear resistance and hardness of three types of artificial resin denture teeth. Methods Three types of resin teeth were evaluated, including the conventional acrylic resin teeth--Heraeus （A）, the cross-linked acrylic resin teeth--Excellence IPN （B） ,and the composite resin teeth--Endura Posterior （C）. The three-body wear test was performed using a custom made pin on disc chewing simulator. Volume and vertical loss were measured using 3-dimensional （3-D） surface profilometer after wear test. The worn surfaces were observed with a scanning electron microscope （SEM）. The microhardness of resin teeth was measured using Vickers hardness method. Results Composite resin teeth （ 0. 415mm3 and 45. 503um ） demonstrated significantly lower wear values than conventional （ 0. 847mm3and 70. 041urn） and cross- linked acrylic resin teeth （ 0. 675mm3and 60. 648 urn） （P 〈0.01 ）. No significant difference was found between the wear of conventional acrylic resin teeth and that of cross-linked acrylic resin teeth （P 〉 0.05 ）. The hardness was 19.40 HV for A, 23.36 HV for B and 29.00 HV for C, showing a rank of C 〉 B 〉 A （ P 〈 0. O1 ）. The negative correlation between the subtance loss and hardness of the three types resin teeth was significant. Condusions There was significant difference among the wear resistances of the three types of resin teeth. Composite resin teeth was more wear resistant than the other two types. Cross-linked acrylic resin teeth showed slightly improved in wear resistance compared to conventional acrylic resin denture teeth. A positive correlation between wear resistance and hardness was found in this study.