分光光度仪比较四种常用全瓷冠在三种基底表面的色度学参数

摘要

AIM:To evaluate the colorimetric parameter of 3 dark color abutments overlaid by 4 all-ceramic crowns using a digital dental spectrophotometer. METHODS: Abutments of Co-Cr alloys, Au-Pt alloys and ND8 (n=10) were made and were respectively tried in 4 groups of all-ceramic crowns (Procera aluminia, Procera zirconi-a, Lava zirconia and IPS E. max glass-ceramic lithium disilicate-reinforced monolithic crown) (n=10) respectively. The colorimetric data of the cervical, body and incisal sites of the samples were recorded and analyzed by a spectropho-tometer. The CIE L∗a∗b∗ values were measured again after veneer. The unglazed A2 ( Vitapan Classical) shade tab was used as the control. The L∗a∗b∗values and the color difference between the samples and control were calculated and statistically analyzed. RESULTS: There was significant difference of the lightness and saturation among 3 abut-ments. But after all-ceramic copings were tried in, the difference of the L∗values of the Pro-Alu copings and E. max HO copings decreased greatly. TheΔE value of the Pro-Alu copings was the smallest among all ceramic copings. And the ΔE value of the copings on the ND8 abutment was smallest among 3 abutments. After veneer, the consistency of the L∗ a∗b∗ values of all the copings increased, the IPS E. max HO crowns had very close L∗ values and the Pro-Zir crowns had similar a∗b∗ values in 3 groups of abutments. CONCLUSION:4 ceramic copings can promote the light-ness and hue of the dark abutments. All the copings on the ND8 abutment had small ΔE values. Veneering porcelain can increase the colorimetric match between the abutments to some extent. IPS E. max HO crowns have little difference of lightness and Procera zirconia has little difference of saturation among the abutmens.%目的：：采用分光光度比色仪比较3种深色基底表面4种全瓷冠各部分的色度学参数。方法：制作钴铬合金、金铂合金及ND8色基牙预备体,分别戴入Procera氧化铝、Procera氧化锆、Lava氧化锆、IPS E. max高度不透明压铸陶瓷4种全瓷底冠后,用分光光度仪对其颈部、体部、切端的CIE L∗a∗b∗值进行测定；4组底冠经烧结体瓷后再次戴入3组基底,并按同样方法进行测色。以Vitapan比色板A2色体瓷片为对照,计算各样本的△L∗、△a∗、△b∗；比较各样本与A2的色差值△E。结果：3组基底的明度、彩度相比均有显著差异(P<0.05),戴入4组全瓷底冠后,各组的彩度差异仍较大,氧化铝和压铸陶瓷底冠组的明度一致性好,氧化铝底冠与A2的色差最小,各组基底表面的色差均以ND8基底组最小。烧结体瓷后,各组明度、彩度的一致性均改善,其中压铸陶瓷组的明度一致度最高,Procera氧化锆组的彩度一致性最好,其余各组全瓷冠在3组基底表面仍存在人眼可辨别的差别。结论：4组全瓷底冠均能显著提升深色基底的明度和色调,对ND8基底的遮色能力较高；氧化铝底冠的色差小于其他底冠,压铸陶瓷冠对基底的明度统一性较好,Procera 氧化锆冠对基底的彩度统一性较好。