后牙氧化锆全锆固定桥的抗压强度研究

A study on the compressive strength of full-zirconiafixed bridge for posterior teeth

目的通过不同品牌和不同[牙合]面厚度的锆材研究后牙三单位固定桥的抗压强度。方法通过CAD/CAM技术设计制作右上第一磨牙缺失,右上侧第二前磨牙和第二磨牙为基牙的3种锆材3种厚度共计9组54个氧化锆全锆三单位固定桥。使用的3种锆材:爱尔创、爱迪特、杜塞拉姆,3种锆材的厚度分别为:0.5 mm、0.8 mm、1.0 mm。氧化锆全锆固定桥用RelyXunicem自粘结树脂粘结剂粘固后静置24 h,以1.5 mm[牙合]面厚度的钴铬烤瓷固定桥作为对照组,通过万能试验机静态下加压比较其抗压强度。结果同种锆材不同[牙合]面厚度的抗压强度有显著差异(P<0.05)。同一厚度,不同品牌锆材的抗压强度无显著性差异(P>0.05)。结论不同品牌的锆材对固定桥抗压强度影响较小,不同[牙合]面厚度对固定桥抗压强度影响较大。初步认为氧化锆全锆修复时,1.0 mm的[牙合]面厚度可满足临床需求。

Objective To investigate the compressive strength of three units fixed bridge for posterior teeth by using zirconium materials of different brands andocclusal surface thicknesses.Methods The three units fixed bridge made of zirconium was consisted of two abutment teeth,including the second premolars and second molars on the right upper side with the first molar missing.Three bands of zirconium materials(Upcera,Ai Dite and DOCERAM)with three different thicknesses(0.5mm,0.8mm and 1.0mm)were used,with a total of 9 groups of 54 samples.All the samples were designed and produced by computer-aided design/computer-aided manufacturing(CAD/CAM)technology.The full-zirconia fixed bridge was cemented by RelyXunicem self-adhesive resin cement,followed by standing for 24h.The compressive strength was compared under static pressure with Universal Testing Machine,with the cobalt-chromium porcelain fixed bridge of 1.5mm occlusal surface thickness as the control group.Results There was a significant difference in the compressive strength of the same brand of zirconium with different occlusal surface thicknesses(P<0.05).However,no significant differences were observed in the compressive strength among different brands ofzirconium with the same occlusal surface thickness(P>0.05).Conclusion The fixed bridge compressive strength is less affected by different brands of zirconium,whereas is largely affected by different occlusal surface thicknesses.Based on the above findings,it is preliminarily believed that the 1.0mm occlusal surface thickness can meet clinical needs when using full-zirconiarestorations.