Abrasion of eroded dentin by different manual toothbrushes

The aim of this study was to compare toothbrush abrasion using three different toothbrushes having different filament diameter classified as hard, medium and soft on eroded and non-eroded dentin in vitro.

Method:

60 human dentin specimens were used for this study. Half of each specimen`s surface was covered with a tape to serve as the reference area. The specimens were divided into seven groups [1-6 (n=9) and 7 (n=6)]. The groups 1-3 and 7 were eroded with 1% citric acid (pH 2.3) for 60s and stored in artificial saliva for 15 min. All specimens from groups 1-6 were abraded with an automatic brushing machine (10:30 min, 6300 strokes) using standard abrasive slurry. The specimens were measured by profilometry. The surface loss was recorded by taking the mean of five step heights between the brushed and the non-brushed areas. The data were statistically analysed by Kruskal-Wallis-Test and Mann-Whitney-U-Test (p < 0.05).

Result:

The surface loss of the eroded samples was significantly higher than the non-eroded ones. Within the eroded group there was no significant difference between the toothbrushes. A statistically significant difference was found between soft and hard toothbrushes for the non-eroded group. The mean (SD) (µm) surface loss for the eroded dentin specimens was as follows: soft 1.60 (0.29) (µm), medium 1.51 (0.18) (µm), and hard 1.45(0.17) (µm). For the non-eroded group: soft 0.40 (0.53) (µm), medium 0.35 (0.70) (µm), and hard 0.30 (0.54) (µm).

Conclusion:

Abrasion of eroded dentin did not increase with a decrease in the filament diameter of the bristles.