A Randomized Clinical Trial on Hydrogen Peroxide Whitening Systems: Prefilled Trays Versus Whitening Strips

This randomized clinical trial evaluated the efficacy, safety, and patient satisfaction of hydrogen peroxide (HP)-based whitening systems, comparing prefilled trays (PT) with different application times and whitening strips (WS).

Participants were randomly allocated into three groups (n = 40): PT-30 (11% HP, 30 min/day); PT-60 (11% HP, 60 min/day); and WS (9.5% HP, 60 min/day). Treatments were applied once daily for 7 days. Tooth color was assessed at baseline and after 1, 3, 7, and 21 days using shade guide (ΔSGU) and spectrophotometer (ΔE₀₀ and ΔWI_D). Tooth sensitivity, gingival condition, and patient satisfaction were also assessed.

Overall, groups treated for 60 min/day showed greater tooth color change, regardless of the whitening system (PT-60 and WS). After 21 days, this whitening effect was maintained, with PT-60 showing greater color change (ΔE₀₀) than PT-30 (mean difference, 1.509; 95% CI, 0.551 to 2.468; p = 0.001). Tooth sensitivity was low and similar among groups. Gingival irritation occurred more frequently in PT-60 but was mild and transient. Participants reported satisfaction and comfort/retention with both systems.

No significant differences in color change were detected between prefilled trays and whitening strips applied for 60 min daily. Reducing tray application time to 30 min resulted in less color change after 7 days of treatment. No severe adverse effects were observed at final assessment, and both systems were well accepted by participants.

Hydrogen peroxide-based whitening systems using prefilled trays or whitening strips offer safe, effective, and patient-friendly options for providing noticeable color change.