Sealants for primary molar teeth


The use of fissures sealants for caries prevention in the permanent teeth is well established. Moderate certainty evidence from a 2017 Cochrane review (Dental Elf – 31st Jul 2017) found caries reduction of between 11-51% at two years following sealant placement. Sealant placement for children and adolescents is recommended by a number of professional bodies and guidelines. While sealant placement on primary molars is frequently practices there is greater uncertainty about their effectiveness.

The main aim of this Cochrane review was to evaluate the effects of sealants compared to no sealant or a different sealant in preventing pit and fissure caries on the occlusal surfaces of primary molars in children.


Searches were conducted in the Cochrane Oral Health’s Trials Register, Cochrane CENTRAL, Medline, Embase, and the World Health Organization (WHO) International Clinical Trials Registry Platform. Two reviewers independently selected studies extracted data and assessed risk of bias using the Cochrane domain-based tool. Parallel group or split mouth design randomised controlled trials (RCTs) of sealants on the occlusal surfaces of primary molars were considered. For the primary outcome of caries incidence (presence or absence of at least one new carious lesion) and other dichotomous outcomes odds ratios (ORs) and 95% confidence intervals (CI) were calculated. GRADE methodology was used to assess the certainty of the evidence.


  • 9 RCTs (1 parallel, 8 split mouth design) involving 1120 children (1977tooth surfaces) were included.
  • All the studies were considered to be at a high risk of bias.
  • 1 study compared fluoride‐releasing resin‐based sealant with no sealant.
    • 2 studies compared glass ionomer‐based sealant with no sealant.
    • 2 studies compared glass ionomer‐based sealant with resin‐based sealant
    • 2 studies compared fluoride‐releasing resin‐based sealant with resin‐based sealant
    • 1 study compared composite with fluoride‐releasing resin‐based sealant
    • 1 study compared autopolymerised sealant with light polymerised sealant
  • 3 studies evaluated sealants versus no sealant providing data for the primary outcome. Due to study heterogeneity no meta-analyses were conducted.
    • At 24 months, there was insufficient evidence of a difference in the development of new caries lesions for the fluoride‐releasing sealants or no treatment groups (Becker Balagtas odds ratio (BB OR) = 0.76 (95%CI; 0.41 to 1.42) [Low certainty evidence].
    • For glass ionomer‐based sealants, the evidence was equivocal; 1 study found insufficient evidence of a difference (follow‐up 12 and 30 months) OR= 0.97(95%CI; 0.63 to 1.49), while another with 12‐month follow‐up found a large, beneficial effect of sealants OR =0.03 (95%CI;0.01 to 0.15) [Low certainty evidence].
  • 6 trials (411 children) compared different sealant materials with 4 providing data for the primary outcome. Data was not pooled. New caries incidence was typically low across the different sealant types evaluated. [Very low certainty evidence].
  • Only 1 study assessed and reported adverse events, the nature of which was gag reflex while placing the sealant material.


The authors concluded: –

The certainty of the evidence for the comparisons and outcomes in this review was low or very low, reflecting the fragility and uncertainty of the evidence base. The volume of evidence for this review was limited, which typically included small studies where the number of events was low. The majority of studies in this review were of split-mouth design, an efficient study design for this research question; however, there were often shortcomings in the analysis and reporting of results that made synthesising the evidence difficult. An important omission from the included studies was the reporting of adverse events. Given the importance of prevention for maintaining good oral health, there exists an important evidence gap pertaining to the caries-preventive effect and retention of sealants in the primary dentition, which should be addressed through robust RCTs.


This review has been conducted following the usual Cochrane procedures. Only 9 small tudies could be included with all the included studies being considered to be at high risk of bias mainly because of a lack of blinding. Consequently, there this limited evidence for the effectiveness of sealants in primary teeth. Well conducted and reported RCTs are needed to assess the effectiveness of sealants in the primary dentition.


Primary Paper

Ramamurthy P, Rath A, Sidhu P, Fernandes B, Nettem S, Fee PA, Zaror C, Walsh T. Sealants for preventing dental caries in primary teeth. Cochrane Database Syst Rev. 2022 Feb 11;2:CD012981. doi: 10.1002/14651858.CD012981.pub2. PMID: 35146744.

Other references

Cochrane Oral Health Blog – Sealants for preventing decay in baby teeth

Dental Elf – 31st Jul 2017

Fissure sealants effective in preventing caries in children and adolescents

Dental Elf – 9th Nov 2020

Caries prevention in children: Fluoride varnishes or sealants?



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