OBJECTIVETo investigate the influence of repeated sintering on the color of two porcelain-fused-to-titanium, and the differences between the two porcelains.

METHODSThirty samples were prepared and sintered for 9 times. The color of samples were measured following sintering 1, 3, 5, 7, 9 times by ShadeEye NCC colorimeter according to two brands of porcelains with CIE1976L*a*b* color system, and calculated relevant chrome, chromatism and hue, and statistical analysis.

RESULTSWhen two brands of porcelains were sintered 5 times, the color parameters had no significant change and sintered continuely, the color parameters of L* and a* had obvious changes, but can't be observed by eyes.

CONCLUSIONThe color parameters of titanium-porcelains have no significant change after repeated sintering.