AbstractObjectivesThis study was aimed to obtain an experimental bleaching agent by adding casein phosphopeptide‐amorphous calcium phosphate (CPP‐ACP) in order to eliminate the mineral loss on the tooth surface after bleaching and to evaluate the bleaching effectiveness.Materials and MethodsIn this study, experimental bleaching agents containing 1%, 3% CPP‐ACP and without CPP‐ACP were obtained. Bleaching effectiveness (color change), the effect of bleaching agents on mineral content (energy dispersive x‐ray spectroscopy), surface morphology (scanning electron microscope), and surface hardness of enamel (Vicker's microhardness) before and after bleaching were evaluated. The obtained data were statistically analyzed.ResultsWhen the bleaching levels of the groups were compared, no statistically significant difference was observed between the control and 1% CPP‐ACP groups (p > 0.05) while the addition of 3% CPP‐ACP decreased significantly the effectiveness of the bleaching agent (p < 0.05). When the effects of experimental bleaching agents on surface hardness were examined, while the enamel surface hardness decreased statistically significantly after application in the control group (p < 0.05), no statistically significant change was observed in surface hardness after the application of 1% CPP‐ACP containing bleaching agent (p > 0.05). However, a statistically significant increase was observed in surface hardness after the application of 3% CPP‐ACP containing bleaching agent (p < 0.05). When the Ca and P ratio of the groups were compared, no statistically significant difference was observed between the control and 1% CPP‐ACP groups (p > 0.05), while they increased significantly in 3% CPP‐ACP group (p < 0.05).ConclusionsThe addition of 1% CPP‐ACP to the bleaching agent had positive effects on the mineral content and surface hardness of the enamel, and did not negatively affect the whitening effectiveness.Clinical SignificanceAdding CPP‐ACP to the bleaching agent at appropriate concentrations can eliminate possible negative effects without compromising the effectiveness of the bleaching agent.