What do systematic reviews say?

Interdental brushing plus toothbrushing vs Toothbrushing alone

Interdental brushing plus toothbrushing may leads to lower plaque compared with toothbrushing alone (low certainty).

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

  1 month
  SMD -1.07 [-1.51, -0.63]
  2 studies · 93 participants
  Low
• Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults 2013 · Cochrane All outcomes

  4 weeks (1 month)
  MD -0.95 [-1.34, -0.56]
  1 study · 62 participants
  Very low

Interdental brushing plus toothbrushing vs Flossing plus toothbrushing

It is very uncertain whether interdental brushing plus toothbrushing changes plaque compared with flossing plus toothbrushing (very low certainty).

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

  1 month (4 to 6 weeks)
  SMD -0.47 [-0.84, -0.11]
  5 studies · 290 participants
  Very low
• Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults 2013 · Cochrane All outcomes

  1 month (4 to 6 weeks)
  SMD 0.10 [-0.13, 0.33]
  7 studies · 326 participants
  Low
• Interdental brushing for the prevention and control of periodontal diseases and dental caries in adults 2013 · Cochrane All outcomes

  3 months (12 weeks)
  SMD -2.14 [-5.25, 0.97]
  2 studies · 107 participants
  Very low

Rubber/elastomeric cleaning stick plus toothbrushing vs Flossing plus toothbrushing

It is very uncertain whether rubber/elastomeric cleaning stick plus toothbrushing changes plaque compared with flossing plus toothbrushing (very 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
  SMD -0.08 [-0.46, 0.29]
  6 studies · 273 participants
  Very low

Wooden cleaning stick plus toothbrushing vs Toothbrushing alone

It is very uncertain whether wooden cleaning stick plus toothbrushing changes plaque compared with toothbrushing alone (very low certainty).

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

  3 months
  MD -0.03 [-0.13, 0.07]
  1 study · 24 participants
  Very low

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

It is very uncertain whether rubber/elastomeric cleaning stick plus toothbrushing changes plaque compared with interdental brushing plus toothbrushing (very 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
  SMD 0.08 [-0.33, 0.49]
  2 studies · 92 participants
  Very low

Wooden cleaning stick plus toothbrushing vs Flossing plus toothbrushing

It is very uncertain whether wooden cleaning stick plus toothbrushing changes plaque compared with flossing plus toothbrushing (very low certainty).

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

  3 months
  MD 0.02 [-0.06, 0.10]
  1 study · 24 participants
  Very low

Oral irrigation plus toothbrushing vs Toothbrushing alone

Oral irrigation plus toothbrushing showed no clear difference in plaque compared with toothbrushing alone (low certainty).

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

  1 month
  SMD -0.16 [-0.41, 0.10]
  3 studies · 235 participants
  Low

Flossing plus toothbrushing vs Toothbrushing alone

It is very uncertain whether flossing plus toothbrushing changes plaque compared with toothbrushing alone (very low certainty).

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

  1 month
  SMD -0.42 [-0.85, 0.02]
  7 studies · 542 participants
  Very low

Rubber/elastomeric cleaning stick plus toothbrushing vs Toothbrushing alone

It is very uncertain whether rubber/elastomeric cleaning stick plus toothbrushing changes plaque compared with toothbrushing alone (very low certainty).

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

  1 month
  MD -0.22 [-0.41, -0.03]
  1 study · 30 participants
  Very low

Oral irrigation plus toothbrushing vs Flossing plus toothbrushing

It is very uncertain whether oral irrigation plus toothbrushing changes plaque compared with flossing plus toothbrushing (very low certainty).

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

  1 month
  SMD 0.31 [-0.08, 0.70]
  2 studies · 133 participants
  Very low

Routine scale and polish provided by a dentist vs Routine scale and polish provided by a dental care professional (dental therapist or hygienist)

The review found no eligible studies for this question.

• Routine scale and polish for periodontal health in adults 2018 · Cochrane All outcomes
  no estimate extracted
  0 studies
  No studies found

Routine scale and polish every 6 months vs Routine scale and polish every 12 months

Routine scale and polish every 6 months showed no clear difference in plaque compared with routine scale and polish every 12 months (low certainty).

• Routine scale and polish for periodontal health in adults 2018 · Cochrane All outcomes

  24 months
  MD -0.04 [-0.13, 0.05]
  1 study · 207 participants
  Low

Routine scale and polish at a fixed interval vs No scheduled scale and polish treatment

Planned, regular routine scale and polish (6-monthly; 12-monthly… showed no clear difference in plaque compared with no scheduled scale and polish treatment (low certainty).

• Routine scale and polish for periodontal health in adults 2018 · Cochrane All outcomes

  24 months · 6-monthly (12-monthly parallel)
  MD -0.04 [-0.13, 0.05]
  1 study · 207 participants
  Low

Chlorhexidine mouthwash vs placebo

Chlorhexidine mouthwash reduced Plaque Index versus placebo, but certainty is very low.

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

  ≤ 3 months
  Plaque Index was significantly reduced compared to placebos according to two studies [20; 32].
  2 studies
  Very low

Periodontal treatment (scaling and root planing, polishing, or surgery), alone or with oral hygiene counselling, antiseptics, or antimicrobials vs no treatment

• Treating periodontal disease for preventing adverse birth outcomes in pregnant women 2017 · Cochrane All outcomes
  Reported as a secondary periodontal outcome (Analysis 1.8); results not meta-analysed due to considerable heterogeneity (I2 91% to 100%); reduction in favour of periodontal treatment.
  2 studies
  GRADE not reported

Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs usual care or no treatment

• Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal diseases 2007 · Cochrane All outcomes
  The impact of psychological interventions on clinical markers was assessed in three studies (Little 1997; Stewart 1991; Weinstein 1996). All three found that psychological interventions resulted in improved plaque…
  3 studies
  GRADE not reported

Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs attention control

• Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal diseases 2007 · Cochrane All outcomes
  Weinstein 1996 reported that the psychological intervention led to improvements in plaque score greater than that noted in the attention control group; however the sample size in each arm was very small (n=5) and the…
  2 studies
  GRADE not reported

Psychological intervention based on a specified psychological model/theory (to increase adherence to oral hygiene instructions) vs Educational intervention (oral hygiene education/instruction)

• Psychological interventions to improve adherence to oral hygiene instructions in adults with periodontal diseases 2007 · Cochrane All outcomes

  5 weeks (2 weeks post-intervention)
  Stewart 1991: while the educational intervention group and the cognitive behavioural intervention group both showed significant differences compared to the control group in plaque scores, the cognitive behavioural…
  1 study · 50 participants
  GRADE not reported

Unilateral cleft lip and palate (UCLP) vs Bilateral cleft lip and palate (BCLP)

Plaque index does not differ significantly between unilateral and bilateral cleft lip and palate (MD -0.13, 95% CI -0.38 to 0.12; ungraded).

• 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 (Thailand and USA)
  MD -0.13 [-0.38, 0.12]
  2 studies · 117 participants
  GRADE not reported

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

Persons with orofacial cleft have a higher plaque index than healthy controls (MD 0.29, 95% CI 0.24 to 0.34; 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 0.29 [0.24, 0.34]
  6 studies · 1618 participants
  Low