Joshi 2019.

Study characteristics
Methods	Design: hybrid RCT with split‐mouth design (for comparison of retention of different sealant types) Number of participants: 111 Setting: paediatric dental department of a dental college Country: India Unit of randomisation: 2‐stage randomisation. At first, tooth pairs were randomised into study and control groups (sealant vs no sealant). Next, in study group alone, each tooth in a tooth pair was randomised to receive additional light curing or not Unit of analysis: tooth Follow‐up mean: 1 year Dropout: 10 teeth (8 teeth in study group and 2 teeth in control group)
Participants	Number randomised: 180 pairs of primary second molars Number analysed: 175 pairs of primary molars Age: mean 4.19 years (range 3–5 years) Sex: 64 boys and 47 girls Mean dmft score: 8.45 SD 6.4 in study group and 8.35 SD 5.4 in control Inclusion criteria: fully erupted primary teeth with ≥ 1 pair of bilateral maxillary/mandibular caries‐free primary second molars, no history of preventive treatment in preceding 6 months, high risk of developing caries Exclusion criteria: permanent molars, medically compromised, children with physical limitation Baseline caries risk of participants: high caries risk
Interventions	2 treatment arms Study group subdivided into 2: high‐viscosity GIC (Ketac Universal, 3M oral care, St Paul, Minnesota, USA) high‐viscosity GIC (Ketac Universal, 3M oral care, St Paul, Minnesota, USA) with additional light curing using blue lex LD 1.5 monitex, Taiwan for 60 seconds Control group: without sealant Co‐intervention: demonstration using videos and models for proper tooth brushing; all participants brushed twice daily with low‐fluoride toothpaste in all groups.
Outcomes	Study primary outcome Caries incidence Study secondary outcomes Sealant retention assessed as no loss, partial loss and complete loss Marginal discolouration Caries diagnostic criteria: visual using ICDAS
Notes	Funding: none (additional information provided by the author) Trial register: registered (CTRI/2017/10/010248) Inter‐evaluator consistency: kappa values were 0.6 for dental caries and 0.7 for sealants Sample size: not calculated Personal communication: Sakshi 2019
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Low risk	Quote: "lottery method, even numbers for the study group and odd numbers for the control group, another round of randomisation was also done by asking the child to pick up the chit with right or left written on it."
Allocation concealment (selection bias)	Unclear risk	Comment: additional information provided by the author as allocation concealment done. However, no information provided on how it was done.
Blinding of participants and personnel (performance bias)‐Participants	High risk	Comment: children would be aware that they were receiving sealant or no sealant or an additional light‐curing technique.
Blinding of participants and personnel (performance bias)‐ Operator	High risk	Comment: additional information provided by the author that operator was not blinded as single operator performed all the intervention. Comment: blinding operator was not possible as 1 required light curing and the other did not.
Blinding of outcome assessment (detection bias) All outcomes	High risk	Quote: "Assessors were blinded." Comment: blinding outcome assessor not possible to compare sealant with no sealant.
Incomplete outcome data (attrition bias) All outcomes	Low risk	Quote: "At the first follow up a total dropout of 8 teeth in study group and 2 teeth in control group was recorded. No further dropouts occurred." Comment: drop‐out low and similar across groups. Reasons for drop‐out due to patient non‐attendance at clinical examination.
Selective reporting (reporting bias)	Low risk	Comment: all prespecified outcomes were reported.
Other bias	Low risk	No evidence of any other bias.