[Effect of pigmentation on the strength of dental Y-TZP/porcelain bilayered structure].
OBJECTIVE
To investigate the effect of two methods of pigmentation on the flexural strength of dental Y-TZP/porcelain layered structure.


METHODS
KaVo zirconia substructures were pigmented by dipping presintered blocks in the coloring solution VITA LL1 and LL5, and colored TZ-3YS zirconia substructures were fabricated by adding pigments before isostatic pressing. The colors No.1 and No.5 were used for the test. The specimens were made in monolithic or bilayered forms, and the flexural strength was tested. XRD and SEM with EDX were used to analyze the characteristics of the surface structure.


RESULTS
In KaVo group, no significant differences were found in the flexural strength between white and LL1 and LL5 colored monoclinic materials, nor in bilayered structures. While in TZ-3YS group, significant differences were noted in the flexural strength between color No.5 white and color No.1 monoclinic materials, but not between the latter two subgroups. The flexural strength was significantly lowered by veneering with porcelain in both zirconia groups, and similar findings were observed with the monoclinic materials. Only the tetragonal phase was detected in both of the zirconia groups.


CONCLUSIONS
Pigmentation has no apparent effects on the bonding strength between the veneering porcelain and zirconia. Both coloring methods are appropriate when the concentration of the pigments is under deliberate control.
Ma
Ting-ting
TT
Department of Prosthodontics, General Hospital of PLA, Beijing 100853, China. 93111498@163.com
Yi
Yuan-fu
YF
Shao
Long-quan
LQ
Liu
Hong-chen
HC
Tian
Jie-mo
JM
Hou
Kang-lin
KL
Zhang
Wei-wei
WW
Wen
Ning
N
Deng
Bin
B
D001840:Dental Bonding; D003764:Dental Materials; D003776:Dental Porcelain / Q000737:chemistry*; D003799:Dental Stress Analysis; D003801:Dental Veneers; D008422:Materials Testing; D010858:Pigmentation; D013718:Tensile Strength; D015019:Yttrium / Q000737:chemistry*; D015040:Zirconium / Q000737:chemistry*
D003764:Dental Materials; C499362:yttria stabilized tetragonal zirconia; D003776:Dental Porcelain; D015019:Yttrium; D015040:Zirconium