What do systematic reviews say?

Probiotics vs placebo or control

Only one trial (Mishra 2014) reported S. viridans count, showing a higher count with probiotics (MD 0.40 CFU/mL, 95%CI 0.33 to 0.47); not pooled or GRADE-rated.

• Efficacy of Probiotic Consumption on Oral Outcomes in Children and/or Adolescents: A Meta-Analysis. 2024 All outcomes

  6 months · Healthy children and/or adolescents (<18 years) without systemic disease; RCTs from multiple countries (India, Thailand, Spain, Australia, New Zealand, Sweden, Poland, Colombia, Saudi Arabia); mostly school/community and clinic settings · Single study (Mishra 2014); not pooled
  MD 0.40 [0.33, 0.47]
  1 study · 60 participants
  GRADE not reported

Slum / urban-disadvantaged setting vs Non-slum urban / general-urban / national population

Indigenous/alternative cleaning tools and home remedies are widely used, more so in rural/slum groups; ungraded.

• Systematic review of oral health in slums and non-slum urban settings of Low and Middle-Income Countries (LMICs):… 2024 All outcomes

  Cross-sectional · Urban slums and non-slum/general-urban settings, LMICs · Rural/slum vs urban
  Alternative implements included toothpowder, chewing-stick, neem, charcoal, sand, snuff, salt, miswak, cotton wool and the fingers; native/indigenous tools were used more by rural and slum/disadvantaged residents than…
  Studies not reported
  GRADE not reported

Cleft lip and/or palate (CL/P) vs No cleft lip and/or palate (non-CL/P)

No difference in mean Streptococcus mutans presence was reported; GRADE was not reported.

• Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and periodontal… 2024 All outcomes
  SMD 1.78 [1.36, 2.19]
  2 studies · 175 participants
  GRADE not reported

Intervention not reported

• Teledentistry accuracy for caries diagnosis: a systematic review of in-vivo studies using extra-oral photography… 2024 All outcomes

  Overall narrative conclusion across included studies
  Study conclusion (narrative) 17 of 19 studies concluded photographic diagnostic accuracy comparable to visual caries assessment
  19 studies
  GRADE not reported

Intervention not reported

• Strategies to integrate oral health into primary care: a systematic review. 2023 All outcomes
  1 study reported an unfavourable outcome
  1 study
  GRADE not reported

Chlorhexidine mouthwash vs placebo

Chlorhexidine mouthwash reduced Mutans streptococci 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
  Colony count of MS was significantly reduced compared to placebos according to three studies [34; 48; 52]; colony count of MS was slightly reduced compared to placebo in a short time in one study [40].
  4 studies
  Very low

Chlorhexidine mouthwash vs Blank control

Chlorhexidine mouthwash reduced Mutans streptococci versus blank control, but certainty is very low.

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

  ≤ 3 months
  Colony count of MS was significantly reduced compared to blank control according to one study [53]; one study reported a significant reduction compared to baseline [51].
  2 studies
  Very low

Herbal mouthwash vs placebo

Herbal mouthwash reduced some plaque-related indices versus placebo, with low-certainty evidence.

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

  ≤ 3 months
  PI was significantly reduced compared to placebo [56]; VPI was significantly reduced compared to placebo [41]; PI was insignificantly reduced compared to placebo [19].
  3 studies
  Low

Fluoride mouthwash vs Blank control

Short-term fluoride mouthwash reduced Mutans streptococci, but certainty is very low.

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

  ≤ 3 months
  Colony count of MS was significantly reduced compared to baseline according to two studies [33; 34].
  2 studies
  Very low
• The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic treatment:… 2023 All outcomes

  ≥ 12 months
  Colony count of MS was similar to blank control according to two studies [37; 59].
  2 studies
  Very low

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

Chlorhexidine mouthwash vs Blank control

Chlorhexidine mouthwash may reduce the Plaque Index versus blank control in the short term (WMD -0.70, 95% CI -1.12 to -0.27), but the evidence is very uncertain (very 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)
  WMD -0.70 [-1.12, -0.27]
  4 studies · 188 participants
  Very low

Cetylpyridinium chloride mouthwash vs Blank control

CPC mouthwash may reduce plaque-related indexes versus blank control in the short term, but the evidence is very uncertain (very 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)
  BBPI was significantly reduced compared to blank control [47]. PI was significantly reduced compared to blank control [50]. The amount of dental plaque was significantly reduced compared to baseline [38].
  3 studies
  Very low

Herbal mouthwash vs placebo

Herbal mouthwash reduced Mutans streptococci 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
  Colony count of MS was significantly reduced compared to placebo [52]; colony count was slightly reduced compared to placebo in a short time in one study [40].
  2 studies
  Very low

Fluoride mouthwash vs Blank control

Short-term fluoride mouthwash has uncertain effects on gingival inflammation-related indexes versus blank control (very 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)
  MGI' and BI' was significantly reduced compared to baseline [34]. BOP and GI was slightly lower compared to blank control [46].
  2 studies
  Very low

Fluoride mouthwash vs Blank control

Long-term fluoride mouthwash showed mixed plaque-index effects, with very low-certainty evidence.

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

  ≥ 12 months
  PI was similar to blank control [37]; API was slightly reduced compared to blank control and significant at 6 and 9 months [59].
  2 studies
  Very low
• The efficacy of mouthwashes on oral microorganisms and gingivitis in patients undergoing orthodontic treatment:… 2023 All outcomes

  ≤ 3 months
  TI was significantly reduced compared to baseline [34]; PI was significantly reduced compared to baseline but similar to blank control [46].
  2 studies
  Very low

Fluoride mouthwash vs Blank control

Long-term (>=12 months) fluoride mouthwash may make little or no difference to Lactobacilli colony counts versus blank control (very low certainty).

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

  >=12 months (long-term) · Orthodontic patients undergoing orthodontic treatment (randomized controlled trials; multiple countries)
  Colony count of LB was similar to blank control according to two studies [37, 59].
  2 studies
  Very low

Chlorhexidine mouthwash vs Blank control

Chlorhexidine mouthwash may reduce the Gingival Index versus blank control in the short term (WMD -0.54, 95% CI -0.96 to -0.13), but with very high heterogeneity the evidence is very uncertain (very 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)
  WMD -0.54 [-0.96, -0.13]
  6 studies · 274 participants
  Very low

Herbal mouthwash vs placebo

Herbal mouthwash reduced gingival inflammation-related indices 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
  GBI was significantly reduced compared to placebo [41]; GBI was significantly reduced compared to placebo [56]; BI was significantly reduced compared to placebo [40].
  3 studies
  Very low

Herbal mouthwash vs Blank control

Herbal mouthwash probably reduces the Gingival Index versus blank control in the short term (WMD -0.20, 95% CI -0.32 to -0.09; moderate 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)
  WMD -0.20 [-0.32, -0.09]
  3 studies · 132 participants
  Moderate

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