The effect of newly introduced bleaching agent listerine versus the conventional carbamide peroxide on the ultrastructure and microhardness of tooth enamel

الملخص EN

Background : Tooth bleaching is one of the most conservative and cost-effective dental treat-ments to enhance a person’s smile.

Aim: The aim of this study was to evaluate the effect of the newly introduced prebrush bleaching agent Listerine versus carbamide peroxide on the ultra-structure and micro-hardness of the enamel.

Materials and Methods: Thirty non-carious sound human premolars extracted for orthodontic reasons.

Teeth samples were divided equally into three groups.

Group Ӏ served as control group where specimens were immersed in artificial sali-va, group ӀӀ treated with 22 % carbamide peroxide for 5 sessions per day 15 minutes for 60 days and group ӀӀӀ treated with Listerine pre-brush rinse for 5 sessions per day 15 minutes for 60 days, in between the sessions teeth were kept in artificial saliva.

At the end of the experiment, all teeth were hemi-sectioned longitudinal in mesio-distal direction to form 60 specimens.

The lingual halves of all the groups were used for measuring enamel micro-hardness, while buccal halves were examined by scanning electron microscope (SEM) to detect any ultrastructural changes of enamel of the different groups.

Results: SEM results showed morphological altera-tions on the enamel surface of group ӀӀ and group ӀӀӀ compared with control group Ӏ as ap-peared surface pitting, porosity, irregularity, roughness, craters like depression and micro-cracks.

Results of enamel surface micro-hardness showed no significant differences were found among the bleaching groups (ӀӀ-ӀӀӀ) (p = 0.371).

However, all bleaching agents produced a signifi-cant increase in the mean value of micro-hardness of enamel compared to the untreated control group (Ӏ) as there are highly significant between group Ӏ and other groups as group ӀӀ (p = 0.003) and group ӀӀӀ (p = 0.026).

Conclusion bleaching abuse had a negative influence on the morpholo-gy of enamel and its micro-hardness.

The home dental bleaching should be done with caution.