Electric Toothbrushes use linked to Greater Enamel Loss on Acid-Eroded Teeth: Study

A new study published in the Journal of Dentistry showed that electric toothbrushes were linked to a much higher loss of surface enamel on natural teeth that had been damaged by acid when compared to manual toothbrushes.

During regular oral care procedures, acid erodes tooth enamel, making it more vulnerable to mechanical wear. Even while brushing is necessary to prevent plaque, it might hasten the loss of enamel when the surface is already damaged. The brushing methods, force applications, and abrasive potential of manual and electric toothbrushes vary, which might affect how they treat worn enamel.

Developing evidence-based preventative recommendations requires an understanding of the relative effects of different brushing techniques on enamel integrity. Assessing their effect on acid-eroded enamel can reduce long-term tooth damage and assist direct safer oral hygiene practices. Using genuine human enamel specimens, this study measured both surface tissue loss and subsurface prism modifications in order to assess and compare the enamel wear caused by manual and electric toothbrushing after acid erosion.

To reveal the normal buccal enamel surfaces, 24 removed human molars devoid of cavities were decoronated and sectioned. After being split into two groups (manual and electric), the samples underwent four cycles of citric acid erosion (pH 2.7) and controlled brushing (30 strokes per cycle, totaling 120) with a toothpaste slurry that was not fluoridated.

The normal brushing force was between 290 and 295 grams. Non-contact laser profilometry was used to determine changes in step height, and scanning electron microscopy (SEM) was used to evaluate changes in enamel prisms. Bonferroni's post hoc test (α = 0.05), two-way ANOVA, and the Shapiro-Wilk test (normality) were used for statistical analysis.

Across all erosion-abrasion intervals, electric toothbrushes resulted in considerably more enamel wear than manual brushes (p < 0.0001). For manual brushing, the mean step height rose from 1.38(0.42) µm to 3.65(0.39) µm, while for electric brushing, it climbed from 1.71(0.22) µm to 5.13(0.28) µm.

While electric samples showed lesser alterations (10-15 µm) with an approximate 10 µm interface gap, SEM showed deeper subsurface prism deformation (30-50 µm) in manual samples. Overall, on natural teeth that had been attacked by acid, electric toothbrushes resulted in noticeably more surface enamel erosion than manual toothbrushes.

Source:

Jadeja, S., Austin, R. S., & Bartlett, D. (2026). Comparative Impact of Manual and Electric Toothbrushing on Acid-Eroded Enamel. Journal of Dentistry, 106558. https://doi.org/10.1016/j.jdent.2026.106558