What do systematic reviews say?

Probiotic mouthwash (e.g., Lactobacillus-based) vs Blank control

Probiotic mouthwash has inconsistent effects on Mutans streptococci colony counts versus blank control; 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)
  Colony count of MS was significantly reduced compared to blank control [53]. Colony count of MS was insignificantly increased compared to baseline [33].
  2 studies
  Very low

Non-syndromic cleft lip and palate (CLP) status and its oral microbiota (exposure/grouping) vs Children and adolescents aged 0-18 years without CLP (controls)

A meta-analysis found no significant difference in mean Lactobacillus spp. levels between children with and without CLP, with high heterogeneity; the evidence is ungraded.

• Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and periodontal… 2024 All outcomes

  Multiple countries; pediatric cleft/craniofacial care; saliva, dental plaque, subgingival plaque and nasal/oropharyngeal samples
  For the outcome of the presence of Lactobacillus spp., there were no significant differences between patients with CLP and healthy patients, and the diversity of the studies led to high heterogeneity; however, the p…
  Studies not reported
  GRADE not reported

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

No significant difference in Lactobacillus spp. 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
  MD 1.40 [1.33, 1.47]
  2 studies · 152 participants
  GRADE not reported

Intervention not reported

• Characterization of the oral microbiota and the relationship of the oral microbiota with the dental and periodontal… 2024 All outcomes

  Narrative synthesis: significantly higher in CLP vs controls (Ahluwalia, Lucas, Hassani, Cheng, Sundell)
  no estimate extracted
  5 studies
  GRADE not reported

Placebo rinse vs Pre-treatment (baseline, same group)

Placebo rinse did not significantly change Lactobacillus counts relative to baseline; not GRADE-rated.

• The antiplaque/anticariogenic efficacy of Salvadora persica (Miswak) mouthrinse in comparison to that of… 2019 All outcomes

  Pre- vs post-treatment · In vivo clinical trial (human oral cavity)
  MD 0.34 [-0.50, 1.18]
  2 studies · 30 participants
  GRADE not reported

Salvadora persica (miswak) mouthrinse vs Pre-treatment (baseline, same group)

Salvadora persica rinse reduced Lactobacillus counts relative to baseline; not GRADE-rated.

• The antiplaque/anticariogenic efficacy of Salvadora persica (Miswak) mouthrinse in comparison to that of… 2019 All outcomes

  Pre- vs post-treatment · In vivo clinical trial (human oral cavity)
  MD 1.54 [0.91, 2.17]
  2 studies · 30 participants
  GRADE not reported

Salvadora persica (miswak) mouthrinse vs Placebo rinse

Salvadora persica rinse reduced Lactobacillus counts more than placebo (favours Salvadora persica); not GRADE-rated.

• The antiplaque/anticariogenic efficacy of Salvadora persica (Miswak) mouthrinse in comparison to that of… 2019 All outcomes

  Post-treatment · In vivo clinical trial (human oral cavity)
  MD -1.12 [-1.45, -0.79]
  2 studies · 60 participants
  GRADE not reported