title: Toothbrush abrasivity in a long-term simulation on human dentin depends on brushing mode and bristle arrangement.
abstract: OBJECTIVE
  The aim of this study was to evaluate the susceptibility of dentin to brushing abrasion using four different toothbrushes (rotating-oscillating, sonic and two types of manual toothbrushes) with the same brushing forces.
  
  
  METHODS
  Dentin samples (n = 72) were selected from 72 impacted third molars. Half of the surface of dentin samples was covered with an adhesive tape, creating a protected and a freely exposed area in the same specimen. Brushing was performed with either a: sonic (Sonicare PowerUp, Philips GmbH, Hamburg, Germany), b: oscillating-rotating (Oral B Vitality Precisions Clean, Procter & Gamble, Schwalbach am Taunus, Germany) or two different manual toothbrushes c: flat trim brush head toothbrush (Dr. Best: Original, Glaxo-Smith-Kline, Bühl, Germany) and d: rippled-shaped brush head toothbrush (Blend-a-Dent, Complete V-Interdental, Blend-a-med, Schwalbach, Germany) in a custom made automatic brushing machine. The brushing force was set to 2 N and a whitening toothpaste (RDA = 150) was used. The simulation period was performed over a calculated period to mimic a brushing behavior of two times a day brushing for eight years and six months. Dentin loss was quantitatively determined by profilometry and statistically analyzed by Wilcoxon and Mann-Whitney-U Test (p < 0.05).
  
  
  RESULTS
  The mean (standard deviation) surface loss was 21.03 (±1.26) μm for the sonic toothbrush, 15.71 (±0.85) μm for the oscillating-rotating toothbrush, 6.13 (±1.24) μm for the manual toothbrush with flat trim brush head and 2.50 (±0.43) μm for the manual toothbrush with rippled-shaped brush head. Differences between all groups were statistically significant at p<0.05.
  
  
  CONCLUSIONS
  Using the same brushing force and a highly abrasive toothpaste, manual toothbrushes are significantly less abrasive compared to power toothbrushes for an 8.5-year simulation.
authors.affiliation: Faculty of Health, School of Dentistry, Department of Operative and Preventive Dentistry, Witten/Herdecke University, Witten, Germany.
authors.forename: Mozhgan
authors.identifier: http://orcid.org/0000-0001-6623-8466
authors.initials: M
authors.lastname: Bizhang
authors.affiliation: Faculty of Health, School of Dentistry, Department of Operative and Preventive Dentistry, Witten/Herdecke University, Witten, Germany.
authors.forename: Ilka
authors.initials: I
authors.lastname: Schmidt
authors.affiliation: Department of Periodontics, Department of Cellular Systems and Anatomy, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America.
authors.forename: Yong-Hee Patricia
authors.initials: YP
authors.lastname: Chun
authors.affiliation: Department of Biological and Material Sciences in Dentistry, Witten/Herdecke University, Witten, Germany.
authors.forename: Wolfgang H
authors.initials: WH
authors.lastname: Arnold
authors.affiliation: Faculty of Health, School of Dentistry, Department of Operative and Preventive Dentistry, Witten/Herdecke University, Witten, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Zimmer
mesh_terms: D003804:Dentin / Q000293:injuries; D006801:Humans; D014072:Tooth Abrasion / Q000209:etiology*; D014099:Toothbrushing / Q000009:adverse effects* / Q000379:methods