Objective: Evaluation of vital bleaching treatment for tetracycline stained teeth after CIE La*b* color space. Subject and method: Intervention of uncontrolled clinical trials, the following before-after comparison. The sample size of this study was 78 degree I and II tetracycline stain.78 patients were bleaching with 35 percent H2O2 of system beyond, intervention 3 time, once a week. Result: General for all research subjects and for all 3 groups of teeth (incisors, canines, premolars): .1E increased over time intervention and follow-up, there was statistical significant (p0.01). Over 12 months of follow-up, general deltaE was average increase of 14.7 units, incisors were average increase of 15.6 units, canines were average increase of 19.7 units, premolars were average increase of 8.9 units, there was statistical significant (p0.01). Average value of deltaE at evaluation of 8 times: From 1st to 4th: There was significant increase (average increase of 16.1 units). Next times: Average value was relatively stable, 100 percent achieve to efficacy color change, efficacy of bleaching teeth. Conclusion: Effectiveness of tooth whitening reached at 100 percent and deltaE increased 3 time intervention (16.1 +/- 2.3) it was stable after treatment with a duration of 3 weeks, 3 months, 6 months 12 months (deltaE 14.7 +/- 2.7).