West China Journal of Stomatology ›› 2012, Vol. 30 ›› Issue (4): 417-419.doi: 10.3969/j.issn.1000-1182.2012.04.022

Previous Articles     Next Articles

The effects of firing numbers on the opening total pore volume, translucency parameter and color of dental all-ceramic systems

Li Shuigen1, Pang Liping2, Yao Jiangwu1,2   

  1. 1. Dept. of Prosthodontics, School of Stomatology of Fujian Medical University, Fuzhou 350002, China; 2. Dept. of Prosthodontics, Stomatological Hospital of Xiamen, Xiamen 361003, China
  • Received:2011-08-14 Revised:2011-12-20 Online:2012-08-01 Published:2012-08-01

Abstract:

Objective To evaluate the effects of firing numbers on the total opening pore volume(TPV), translucency parameter(TP) and color of dental all-ceramic systems. Methods Specimens of three kinds of all-ceramics systems were made, i.e. heat pressed all-ceramic(IPS Empress Ⅱ), alumina all-ceramic(In-Cream alumina blanks) and zirconia all-ceramic(Cercon CAD/CAM zirconia). The specimens’TP, lightness(ΔL), chroma(ΔC) and TPV after 1, 3 and 5
firings were measured and calculated by spectrophotometer and surface area/porosity system. The data were analyzed statistically using SAS 8.0 software. Results There were significant differences in TPV, TP, ΔL and ΔC for all-ceramic specimens at same number of firings(P<0.05), i.e. IPS>alumina and zirconia for TPV(P<0.05); IPS>zirconia>alumina for TP and ΔL(P<0.05); IPS and alumina>zirconia for ΔC(P<0.05). The significant differences also presented in TPV, TP,
ΔL and ΔC for a same specimen at different number of firings(P<0.05). With increasing number of firings, TPV decreased, and TP, ΔL and ΔC increased gradually. There were negative linear correlation between number of firings and TPV, TP, ΔL and ΔC(P<0.05). Conclusion Repeated firings will affect TP and ΔL of all-ceramic restorations via the change of TPV.

Key words: firing, all-ceramic, total pore volume, color