OBJECTIVE: To evaluate hydrogen peroxide (HP) permeability into the pulp chamber, color change, and surface morphology promoted by different whitening pens. MATERIAL AND METHODS: Fifty premolars were divided into five groups (n = 10): untreated control
Colgate Optic White Express Whitening Pen (OE-C), Colgate Optic White Overnight Whitening Pen (OW-C), Equate Teeth Whitening Kit (TK-E) and Zimba Teeth Whitening Pen (TW-Z), applied daily for 15 minutes over ten days. HP permeability (μg/mL) was measured using UV-VIS spectroscopy, and color change (ΔE RESULTS: OE-C and OW-C exhibited higher pH, lower HP concentrations, reduced HP penetration (p <
0.05), and a similar surface morphology pattern compared to TK-E and TW-Z. Bleaching efficacy showed no significant differences among the whitening pens (p >
0.05). For ΔE CONCLUSIONS: Whitening pens vary in pH, initial hydrogen peroxide concentration, and hydrogen peroxide penetration
however, these differences do not significantly impact their surface morphology and bleaching effect. CLINICAL SIGNIFICANCE: The use of whitening pens appears promising for achieving effective teeth bleaching after five days of application. However, the detection of hydrogen peroxide within the pulp chamber may increase the risk of tooth sensitivity.