Study	Reason for exclusion
Alvesalo 1975	Not a randomised controlled trial.
Bakhshandeh 2015	Sealant was placed on cavitated caries in dentin on occlusal surface of primary molars.
Borges 2011	The study compared sealants with composite restoration on primary teeth on non‐cavitated dentinal caries.
Buonocore 1970	Not a randomised controlled trial.
Buonocore 1971	Not a randomised controlled trial.
Cline 1979	Not a randomised controlled trial. Study did not have a control group.
Cogo 2009	Not a randomised controlled trial.
Dias 2018	Flowable resin was used as sealant to seal cavitated dentinal caries.
Duggal 1997	The study investigated the effects of different etching times on the retention of sealants on primary and permanent molars and did not have a control group.
Going 1976	Not a randomised controlled trial.
Hesse 2014	Sealant was placed on cavitated caries in dentin on occlusal surface of primary molars.
Honkala 2015	The study compared sealants with fluoride varnish.
Jing 2019	The study compared the effect of fluorine protective paint used with sealant.
Luoma 1973	Not a randomised controlled trial.
Maher 2013	This study compared the effectiveness of different types of etchant on retention of sealants.
Poulsen 1979	This study compared the isolation method on retention of a single fissure sealant.
Provenzano 2010	Not a randomised controlled trial.
Rajic 2000	Not a randomised controlled trial.
Raucci‐Neto 2015	Randomisation was systematic.
Richardson 1977	Not a randomised controlled trial.
Siripokkapat 2018	Randomisation was systematic.
Tang 2018	Not a randomised controlled trial. Study did not have a control group.
Vrbic 1983	Not a randomised controlled trial.
Vrbic 1986	Not a randomised controlled trial.
Vrbic 1999	Not a randomised controlled trial. The study compared the sealant retention between primary and permanent molars.
Zhang 2008	This study compared effectiveness of different types of etchant on retention of sealant.