Study	Reason for exclusion
Glenn 1979	771 participants were divided into 3 groups (control, 1.0 mg tablet per day, and 2.2 mg tablet per day). Allocation method was not described
Glenn 1982	33% of participants were randomly selected from 1374 private practice patients. Group 1: control, Group 2a: sibling of Group 1: no tablet, Group 2b: sibling of Group 1: with prenatal fluoride tablet, Group 3a: no prenatal intervention and no postnatal fluoride tablet, Group 3b: no prenatal intervention with postnatal fluoride tablet, Group 4a: twins with no prenatal intervention and no postnatal fluoride tablet, Group 4b: twins with prenatal fluoride tablet. Groups 3a and 3b are families with only 1 child. All participated patients were observed. It is cohort design
Glenn 1984	Participants were divided into 3 groups (control, postnatal fluoride tablet, and prenatal fluoride tablet). Allocation method was not described
Restrepo 1993	Narrative review