Efficacy of Two Interdental Cleaning Devices on Clinical Signs of Inflammation: A Four-Week Randomized Controlled Trial

J Clin Dent. 2015;26(2):55-60.


Objective: The purpose of this study was to compare the reduction of the clinical signs of inflammation by two power interdental cleaning devices combined with a manual toothbrush.

Methods: Sixty-nine subjects completed this randomized, four-week, single-blind, two-group, parallel clinical study. Subjects were randomly assigned to one of two treatment groups: Waterpik Water Flosser (WF) plus a manual toothbrush; or Sonicare Air Floss Pro (AFP) plus a manual toothbrush. All subjects received both written and verbal instructions and demonstrated proficiency prior to starting the study. Instructions were reviewed at the two-week visit (W2). Data were evaluated for whole mouth, lingual, and facial areas for bleeding on probing (BOP) and Modified Gingival Index (MGI). Plaque data were recorded for whole mouth, lingual, facial, approximal, and marginal areas of the tooth using the Rustogi Modification of the Navy Plaque Index (RMNPI). BOP, MGI, and RMNPI were scored at baseline (BSL), two weeks, and four weeks (W4).

Results: Both groups showed significant reductions in BOP and MGI from baseline for all regions and time points measured (p < 0.001). Both groups showed significant reductions from baseline for all areas at W4 for RMNPI (p < 0.001). The WF group was significantly more effective than the AFP group at reducing bleeding and gingivitis for all areas measured at all time points. At W4, the WF group was 54% more effective for bleeding and 32% for gingivitis (p < 0.001). Plaque accumulation was significantly less at W4 for the WF group compared to the AFP group (28%, p 0.017).

Conclusions: The Waterpik Water Flosser is significantly more effective than the Sonicare Air Floss Pro for reducing clinical signs of inflammation.

Publication types

  • Comparative Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Air
  • Dental Devices, Home Care* / classification
  • Dental Plaque / prevention & control*
  • Dental Plaque Index
  • Equipment Design
  • Erythrosine
  • Female
  • Fluorescent Dyes
  • Follow-Up Studies
  • Gingival Hemorrhage / prevention & control
  • Gingivitis / prevention & control*
  • Humans
  • Male
  • Middle Aged
  • Periodontal Index
  • Single-Blind Method
  • Toothbrushing / instrumentation
  • Treatment Outcome
  • Water


  • Fluorescent Dyes
  • Water
  • Erythrosine