# Phthalimidoperoxycaproic Acid (PAP) Versus Peroxides and Impact on Dental Enamel After Whitening Treatment: An In Vitro Study

## TL;DR

This study compares PAP, a non-peroxide whitening agent, to hydrogen peroxide and carbamide peroxide for dental bleaching, finding PAP to be effective with less enamel damage.

## Contribution

PAP is shown to be a viable alternative to peroxides with similar bleaching efficacy and reduced enamel damage.

## Key findings

- PAP achieved significant color improvement with a ΔWID of 8.82, the highest among the agents tested.
- PAP caused fewer morphological changes and less microhardness reduction in enamel compared to HP and CP.
- All agents provided excellent bleaching results, but only PAP maintained excellent ΔWID values.

## Abstract

Phthalimidoperoxycaproic acid (PAP) emerges as a promising alternative non-peroxide bleaching agent to hydrogen peroxide (HP), offering similar efficacy with potentially less enamel damage. This in vitro study aimed to evaluate and compare the effects of 37.5% HP, 35% carbamide peroxide (CP), and PAP on dental color, enamel surface microhardness, and morphological integrity. Fifty-seven extracted human maxillary incisors were randomly assigned to three groups (n = 18). Thirteen teeth per group were used for color evaluation, four for microhardness, and one for surface morphology analysis. Each group received three whitening sessions (three applications per session) according to the manufacturers’ instructions. Color was assessed before and one week after each session using a spectrophotometer. Lightness increased by 7.19 units (HP), 7.11 (PAP), and 4.43 (CP). ΔWID was 4.48 (HP), 4.16 (CP), and 8.82 (PAP). All agents produced an “excellent” bleaching effect (ΔE00 index); only PAP achieved “excellent” values with the ΔWID index at the end of the study. PAP produced fewer morphological changes on the enamel surface and less reduction in microhardness compared to the untreated control than the other agents evaluated. PAP emerges as an effective alternative for dental bleaching, offering significant color improvement while ensuring minimal alterations to enamel morphology.