Summary of findings for the main comparison. Summary of findings ‐ chlorhexidine varnish.
| Chlorhexidine varnish compared with placebo for the prevention of dental caries in children and adolescents | ||||||
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Patient or population: children and adolescents Settings: school, nursery or dental clinic Intervention: chlorhexidine varnish Comparison: placebo | ||||||
| Outcomes | Illustrative comparative risks* (95% CI) | Relative effect (95% CI) | No of Participants (studies) | Quality of the evidence (GRADE) | Comments | |
| Assumed risk | Corresponding risk | |||||
| Placebo | Chlorhexidine | |||||
| Caries in the primary teeth (24‐months follow‐up) | Two trials with unit of analysis problem. Data imputations indicated no evidence to claim or refute a benefit | |||||
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Caries in permanent dentition (DMFS) (30 to 36 months) Higher values indicate greater caries |
The mean increment in the control group was 5.821 | The increment in the intervention groups was 0.53 higher (1.53 higher to ‐0.47 lower) | ‐ | 690 (2) | ⊕⊝⊝⊝ very low2 | Chlorhexidine varnish concentration 10% varnish and 40% varnish. A further three trials provided some unusable data but indicted no evidence to claim or refute a benefit3 |
| Elevated mutans streptococci levels ≥4 with caries screen (6 to 36 months) | 620 per 10004 | 577 per 1000 (496 to 664) | RR 0.93 (0.80 to 1.07) | 496 (1) | ⊕⊝⊝⊝ very low5 | Chlorhexidine concentration 10% varnish Two other studies reported unusable data but indicated no evidence to claim or refute a benefit6 |
| Adverse events | One study reported no adverse events for ulcers or tooth staining. One study stated “side‐effects due to the CHX treatment were not noted" | |||||
| *The basis for the assumed risk (e.g. the median control group risk across studies) is provided in footnotes. The corresponding risk (and its 95% confidence interval) is based on the assumed risk in the comparison group and the relative effect of the intervention (and its 95% CI). CI: confidence interval; RR: risk ratio | ||||||
| GRADE Working Group grades of evidence High quality: Further research is very unlikely to change our confidence in the estimate of effect. Moderate quality: Further research is likely to have an important impact on our confidence in the estimate of effect and may change the estimate. Low quality: Further research is very likely to have an important impact on our confidence in the estimate of effect and is likely to change the estimate. Very low quality: We are very uncertain about the estimate. | ||||||
1. In the two trials that assessed this outcome, the DMFS increment in the control groups was 5.25 and 6.39, mean 5.82. This value was considered to be a moderate caries increment.
2. We downgraded the quality of the evidence due to risk of bias (high and unclear risk of bias overall) and inconsistency.
3. Conclusions reflected in remaining 3 studies (high risk of bias) with 6‐ to 24‐months follow‐up and chlorhexidine concentrations of 1% and 10%, reporting caries outcomes in permanent dentition that could not be pooled in a meta‐analysis.
4. In the single trial that assessed this outcome as presence or absence of high mutans streptococci levels, the prevalence of high mutans streptococci in the placebo varnish group was 62%.
5. We downgraded the quality of the evidence due to risk of bias (unclear risk of bias overall), imprecision and inconsistency. Mutans streptococci outcomes were reported as mean mutans streptococci levels or presence or absence of high mutans streptococci.
6. Equivocal results reported in 2 other studies (high risk of bias) with 6‐ to 24‐months follow‐up and chlorhexidine concentrations of 1% and 10%, which could not be pooled in a meta‐analysis.