Initial color change and color retention with a hydrogen peroxide bleaching strip.

Purpose:
A randomized, double blind clinical trial was conducted to evaluate initial color improvement and post-treatment color retention following vital bleaching with a strip-based tooth whitening system.

Materials and Methods:
After balancing for baseline color, 57 healthy adults were randomized to either whitening strips with a 5.3% hydrogen peroxide bleaching gel (Crest Whitestrips) or placebo strips without hydrogen peroxide. Maxillary and mandibular anterior teeth were treated twice daily for 30 minutes each over a 2-week period, and efficacy was measured objectively by comparing digital images of teeth collected at baseline, end-of-treatment (Week 2) and 6 months after treatment (Month 6).

Results:
The whitening strip group experienced a highly significant (P< 0.0001) reduction in yellow of-2.0 Ab* units versus baseline and -1.95 Ab* units versus placebo, with similar results noted for the other color parameters in the study. Most of the initial color change remained at 6 months post-treatment, with the whitening strip group continuing to demonstrate highly significant (P< 0.0001) improvements in tooth color relative to baseline and placebo. Age was found to significantly contribute to initial color improvement, with younger subjects experiencing a greater initial reduction in yellowness compared to older participants, but not to post-treatment color retention. The whitening strips were well tolerated, with minor tooth sensitivity and oral irritation representing the most common findings during treatment. There were no persistent or new treatment-related adverse events during the 6-month monitoring period. (Am JDent 2002;15:3-7).

CLINICAL SIGNIFICANCE:
Twice daily use of whitening strips resulted in significant initial color improvement and color retention, without any evidence of persistent or new tooth sensitivity, gingival irritation or other treatment-related adverse events during the post-treatment monitoring period.

Relationship between age and initial color response at week 2. Click to enlarge.