Dasanayake 1993.

Methods	RCT
Participants	62 pregnant women and their foetuses were randomised. Inclusion criteria: women in their third trimester of pregnancy attending the Jefferson County Health Department in Birmingham residing in a fluoridated community with their spouse or significant other as the only other adult with at most one other child at home who: did not plan to breast feed their infant; did not receive any form of anti‐bacterial therapy 3 months prior to enrolment; and who had 2.5 x 104 or more colony forming units (CFU) of MS per mL of unstimulated saliva on at least two of three screening samples obtained during consecutive visits Exclusion criteria: not reported Setting: maternal and infant care program (MIC) of the Jefferson County Health Department in Birmingham, Alabama, USA (study dates not reported) Important health characteristics reported: all included women had 2.5 x 104 or more colony forming units (CFU) of MS per mL of unstimulated saliva on at least two of three screening samples obtained during consecutive visits.
Interventions	Group 1 (n randomised not reported, 23 children were included in the caries assessment at 3 years) Women received L‐NaF antimicrobial solutions to their dentition. The sealant applications (Delton clear shade; Johnson and Johnson, East Windsor, NJ) were applied to all nonrestored occlusal fissures, by a clinician. Around the time of the emergence of the infant's first tooth, a dental hygienist, who was masked to the treatment/control status of the participants, performed a dental prophylaxis consisting of a supragingival scaling, polishing with a rubber cup, water, and pumice, and flossing on the mother. Next, the hygienist applied either the treatment or placebo. The active treatment solution consisted of I2‐NaF solution [1.0 g I2 (USP grade), 1.0 g Kl (USP grade), 53.0 mL glycerin (USP grade), 1.2 g NaF (USP grade) and water to make 100 mL]. The solution was then adjusted to pH 4.5 with 85% H3PO4. consisting of a red disclosing solution [47.0 mL erythrocin dye (Butler Dental Co.), 53.0 mL glycerin, and 47.0 mL water adjusted to pH 4.5 with 85% H3PO4]. All agents were prepared within 2 weeks of application by a pharmacist and stored under refrigeration in coded amber glass syringes to maintain the blindness. Two mL of the agent were administered to the mothers for 5 min every other day over a period of 2 weeks, according to the method described previously. The iodine content of each batch of active agent was confirmed by titration with sodium thiosulfate (30). After application of the last treatment, all mothers were examined by an oral pathologist to evaluate any potential harmful effects of treatment/placebo applications. Number of participants randomised not reported, 23 mother‐child pairs included data outcome for study outcomes. Group 2 (n randomised not reported, 25 children were included in the caries assessment at 3 years) Women received a placebo treatment agent consisting of a red disclosing solution (47.0 mL erythrocin dye (Butler Dental Co.), 53.0 mL glycerin, and 47.0 mL water adjusted to pH 4.5 with 85% H3PO4). Intervention timing: intervention started 6 months after birth (around the time of the emergence of first teeth), and lasted for 2 weeks, with application of the agent for 5 minutes every other day (≤ 6 months intervention duration). Theory or model used as a basis for intervention: not reported All participants: mothers received complete restorative treatment prior to receiving the intervention or placebo treatment.
Outcomes	Data in meta‐analysis for: primary outcome: caries presence in primary teeth; secondary outcome: adverse events for mother or child Narrative text for: child microbiological presence; mother microbiological presence Tabulated data for: adverse effects for mother or child Additional outcomes that had not been prespecified: Child: none reported. Mother: none reported
Notes	Funding: Quote: "This study was supported by contract //NolDE‐42552 from the National Institute of Dental Research". Declarations of interest: not reported
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Quote: “mothers were randomly assigned to either the treatment or control group”.
Allocation concealment (selection bias)	Low risk	Not reported
Blinding of participants and personnel (performance bias) All outcomes	Low risk	For blinding of participants: ensured by use of placebo comparator; for personnel blinding, quote: “Sealants were applied by a clinician not involved in any other aspect of the study in an attempt to maintain the masking...All agents were prepared within 2 weeks of application by a pharmacist and stored under refrigeration in coded amber glass syringes to maintain the blindness."
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Not reported
Incomplete outcome data (attrition bias) All outcomes	Unclear risk	Authors reported that 48/62 of the women and infant pairs randomised completed the study, of which 23 and 25 pairs, respectively, were randomised to the treatment and control groups. The numbers randomised to each group initially was not reported (therefore not possible to compare attrition rates across groups and confidently assess whether this domain was at high or low risk of attrition bias).
Selective reporting (reporting bias)	Unclear risk	Without access to the study protocol, we were unable to confidently assess reporting bias.
Other bias	Low risk	Authors reported that the control and treatment groups were homogenous with respect to age, race, baseline caries experience, and oral bacterial levels; data to demonstrate similarity between the two groups provided. No clear signs of other bias