Hotuman 1998.

Study characteristics
Methods	Design: RCT with split‐mouth design Number of participants: 52 Setting: children were recruited from paediatric dentistry section, municipal dental clinics around municipality of Arhus Country: Denmark Unit of randomisation: teeth within each tooth pair Unit of analysis: tooth pairs Follow‐up: 2–2.3 years Dropout: 1 pair of teeth
Participants	Number randomised: 52 pairs of teeth in 52 children Number analysed: 51 pairs of teeth Age: mean 3.7 years (range 2.11–4.11 years) Sex: 25 boys and 27 girls Mean dmft score at baseline: not mentioned Inclusion criteria: children with pairs of sound primary molars Exclusion criteria: no information provided Baseline caries risk of participants: no information provided
Interventions	2 treatment arms Autopolymerised resin sealant (Delton) Light‐polymerised resin sealant (Prismashield) Co‐intervention: none
Outcomes	Study primary outcomes Sealant retention Caries status at the follow‐up Diagnostic criteria for caries: caries was diagnosed at cavitation level.
Notes	Funding: no information provided Trial register: no information provided Inter‐evaluator consistency: no information provided Sample size: no information provided
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: "The teeth within each tooth pair were randomly assigned to sealing with Delton1 or Prisma‐Shield1." Comment: method of random sequence generation not mentioned.
Allocation concealment (selection bias)	Unclear risk	Comment: no information provided.
Blinding of participants and personnel (performance bias)‐Participants	High risk	Comment: no information provided, but difference in material may not allow for blinding of participants.
Blinding of participants and personnel (performance bias)‐ Operator	High risk	Quote: "All children were examined by the same dentist, who also placed all the sealants." Comment: blinding of operator not possible as 1 was a light‐cured resin and the other was autopolymerising resin.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Comment: blinding of outcome assessor was not possible due to material difference in sealants.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "One pair was omitted because the control tooth had been extracted."
Selective reporting (reporting bias)	Low risk	Comment: all prespecified outcomes reported.
Other bias	Low risk	No evidence of any other bias.