What do systematic reviews say?

Chlorhexidine mouthwash vs Placebo mouthwash

Chlorhexidine mouthwash may reduce pocket probing depth versus placebo in the short term (low certainty).

• The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic treatment:… 2023 All outcomes

  <=3 months (short-term) · Orthodontic patients undergoing orthodontic treatment (randomized controlled trials; multiple countries)
  PD was significantly reduced except mid-lingual site compared to placebo [32]. The changes of PD were significantly higher compared to placebo [56].
  2 studies
  Low

Clear aligners (Invisalign / thermoformed aligners) vs Fixed appliances

Aligners may reduce pocket depth compared with fixed appliances in adults at 6-12 weeks (MD -0.42 mm, 95% CI -0.71 to -0.12; very low certainty).

• Impact of Aligners and Fixed Appliances on Oral Health during Orthodontic Treatment: A Systematic Review and… 2021 All outcomes

  6 to 12 weeks · Adults
  MD -0.42 [-0.71, -0.12]
  2 studies · 62 participants
  Very low

Cleft lip and/or palate (CL/P) vs Healthy controls without cleft

Persons with orofacial cleft have a greater probing pocket depth than healthy controls (MD 0.88, 95% CI 0.82 to 0.95; low certainty).

• Oral health in patients with cleft lip and palate: a systematic literature review and meta-analysis of periodontal and… 2025 All outcomes

  Clinical dental examination; various countries (e.g., Brazil, India, China, Thailand, USA)
  MD 0.88 [0.82, 0.95]
  3 studies · 340 participants
  Low

Metal-free implant abutments (zirconia) vs Metal implant abutments (titanium)

Metal-free implant abutments (zirconia) showed no clear difference in implant probing pocket depth (PPD) compared with metal implant abutments (titanium); GRADE not reported.

• Metal‐free materials for fixed prosthodontic restorations 2017 · Cochrane All outcomes

  12 months
  MD -0.22 [-0.60, 0.16]
  2 studies · 47 participants
  GRADE not reported

Wooden cleaning stick plus toothbrushing vs Flossing plus toothbrushing

The review found no eligible studies for this question.

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  No included study assessed periodontitis.
  0 studies
  No studies found

Oral irrigation plus toothbrushing vs Flossing plus toothbrushing

The review found no eligible studies for this question.

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  No included study assessed periodontitis.
  0 studies
  No studies found

Oral irrigation plus toothbrushing vs Toothbrushing alone

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  Periodontitis measured in one study but useable data not provided (Walsh 1989 reported proportion of sites with >4 mm pocket depth at 3 months but not mean PD; attachment loss measured but no data).
  1 study
  GRADE not reported

Rubber/elastomeric cleaning stick plus toothbrushing vs Flossing plus toothbrushing

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  One study measured periodontitis but the data were not usable (Smith 1988 measured PPD but data unusable).
  1 study
  GRADE not reported

Rubber/elastomeric cleaning stick plus toothbrushing vs Toothbrushing alone

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  One study measured probing pocket depth but no data were reported (Graziani 2017 mentioned PPD as outcome but no data).
  1 study
  GRADE not reported

Interdental brushing plus toothbrushing vs Toothbrushing alone

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  One study measured probing pocket depth but no data were reported (Graziani 2017).
  1 study
  GRADE not reported

Rubber/elastomeric cleaning stick plus toothbrushing vs Interdental brushing plus toothbrushing

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  Two studies measured periodontitis but data not presented or usable (Smith 1988 PPD unusable; Graziani 2017 measured PPD but no data).
  2 studies
  GRADE not reported

Interdental brushing plus toothbrushing vs Flossing plus toothbrushing

Interdental brushing plus toothbrushing showed no clear difference in periodontitis (probing pocket depth) compared with flossing plus toothbrushing (low certainty).

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes

  4 to 6 weeks
  MD -0.06 [-0.27, 0.16]
  3 studies · 107 participants
  Low

Wooden cleaning stick plus toothbrushing vs Toothbrushing alone

The review found no eligible studies for this question.

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  No included study assessed periodontitis as an outcome.
  0 studies
  No studies found

Flossing plus toothbrushing vs Toothbrushing alone

• Home use of interdental cleaning devices, in addition to toothbrushing, for preventing and controlling periodontal… 2019 · Cochrane All outcomes
  One study measured probing pocket depth but no data were reported (Graziani 2017).
  1 study
  GRADE not reported