Summary of findings 2. Glass ionomer fissure sealant or resin‐modified glass ionomer fissure sealant compared with fluoride varnish for preventing dental caries.

Glass ionomer fissure sealant or resin‐modified glass ionomer fissure sealant compared with fluoride varnish for preventing dental caries
Patient or population: children and adolescents Settings: sealant and fluoride varnish applications for school children in Brazil and China Intervention: glass ionomer or resin‐modified glass ionomer sealant applications on occlusal tooth surfaces of permanent first molars Comparison: fluoride varnish applications on occlusal tooth surfaces of permanent first molars
Outcomes	Impact No difference	Number of participants (studies)	Quality of the evidence (GRADE)	Comments
Dentine caries in permanent molars Follow‐up: 1, 2 and 3 years	No difference in caries after 1, 2 and 3 years	3 trials (1 study with 21 evaluated children after 1 yeara; 2 studies with 581 evaluated children at 2 yearsb; 1 study with 393 evaluated children at 3 yearsc)	⊕⊝⊝⊝ Very lowd	No adverse events reported from the interventions (1 study)
*The basis for the assumed risk (e.g. 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

^aOne study with high risk of bias comparing resin‐modified glass ionomer versus fluoride varnish after one year (Florio 2001).
 ^bThe other of the two studies at two years, with incomplete information and analyses, compared chemically cured glass ionomer versus fluoride varnish (Ji 2007). The other study actually evaluated whether additional benefit was derived by using resin‐modified glass ionomer sealants and fluoride varnishes among children receiving regular oral health education (Tagliaferro 2011).
 ^cOne study at three years comparing chemically cured glass ionomer versus fluoride varnish, assessed as having unclear risk of bias (extensive incomplete information and analyses) (Ji 2007).
 ^dDowngraded because a small number of trials had high or unclear risk of bias and used different designs and follow‐up times.