Three Years Long-Term Impact of Powered vs. Manual Toothbrushes on Hypersensitivity and Gingival Recession: A Randomized Controlled Trial

OBJECTIVES: Gingival recessions (GR) are often associated with dentin hypersensitivity (HYP) and can significantly affect patients' oral health-related quality of life. This subgroup-analysis of a previously published study assesses the long-term effects of oscillating-rotating powered (PT) and manual toothbrushes (MT) on HYP in teeth with pre-existing GR and no interproximal attachment loss (RT1) over 36 months. METHODS: Ninety participants with RT1 were divided into PT-/MT-group (n=47/n=43). All participants brushed twice daily with the same fluoride toothpaste. HYP scores were reassessed for 180 index teeth (PT/MT: n=94/n=86); two teeth per participant. HYP was evaluated annually (T0(baseline), T1, T2 and T3) using tactile stimulus with a dental probe (HYP-S) and an air-jet (HYP-L) applied to the index teeth. RESULTS: At T3, HYP-L was significantly reduced in PT but not in MT (p=0.014). From T0 to T3, 60% of PT users showed a decrease in HYP-L, 6.4% remained stable, and 33% experienced an increase, whereas in MT, 36% showed a reduction, 18.6% remained stable, and 45.5% experienced an increase. This was consistent with the GR stabilization reported in the primary analysis. Between T0 to T3 smokers showed a significantly greater reduction in HYP-L than non-smokers (-1.17(1.49) vs. 0.10(2.27); p=0.006), regardless of toothbrush group. Male participants exhibited a more pronounced reduction in HYP-S compared to females (-0.09(1.85) vs. -0.04(1.11); p=0.021). CONCLUSIONS: The tested powered toothbrush reduced HYP-L more than manual toothbrushing over 36 months; HYP-S was unaffected. Findings are exploratory and require confirmation. CLINICAL SIGNIFICANCE: Over 36 months, oscillating-rotating powered brushing was associated with a reduction in air-jet-induced dentin hypersensitivity at RT1-type gingival recession sites. The effect is small and exploratory; powered brushing appears safe in this population but should not be recommended on the basis of hypersensitivity reduction until confirmed in a trial prospectively powered for that endpoint. TRIAL REGISTRATION: This study was prospectively registered in the German Clinical Trials Register (DRKS00015133) on July 25, 2018.