CRD summary

The authors concluded that sealing non-cavitated caries in the pits and fissures of permanent teeth in children, adolescents and young adults was effective in reducing caries progression. The authors' conclusions reflected the results of the review, but some caution was needed given the small number of studies and incomplete reporting of review methods.

Authors' objectives

To determine the effectiveness of dental sealants in preventing the progression of caries lesions in the pits and fissures of permanent teeth.

Searching

MEDLINE (1966 to June 2005), EMBASE (1980 to June 2005) and Cochrane Central Register of Controlled Trials (1st week September 2005) were searched for English language articles using a modified search strategy used by the National Institutes of Health (NIH) Caries Consensus Development Conference. References of retrieved articles were handsearched.

Study selection

Randomised or non-randomised controlled trials or cohort studies measuring the effectiveness of dental sealants on caries progression in permanent teeth were eligible for inclusion. Included studies were of a variety of resin-based and glass-isomer cement (GIC) sealants.

Most included studies were of participants with non-cavitated lesions. The age of participants ranged from six years to 19 years. Included studies were of caries progression defined as demineralisation or loss of tooth structure as measured by direct digital radiography, visual-tactile examination or the Bodecker device. Included studies were from the USA, Canada, Brazil and Zimbabwe.

Two reviewers independently assessed the titles and abstracts to identify articles to retrieve in full text. One reviewer examined all full text articles to identify studies potentially eligible for inclusion. Three reviewers assessed the shortlisted articles to select studies to be included in the review.

Assessment of study quality

Validity was assessed jointly by three reviewers using the following criteria determined by the third US Preventative Services Task force: method of assembling the comparator groups; clarity of definition of the intervention; reliability and validity of outcome measure; and loss to follow up. Each study was awarded an overall rating of study quality.

Data extraction

Data were extracted by two reviewers using a modified version of a form developed by the NIH Caries Consensus Conference. The median percentage of lesions progressing in sealed and unsealed teeth were extracted for each study. The relative risk ratio (RR) and corresponding 95% confidence intervals (CI) were calculated by dividing the percentage of lesions progressing in sealed teeth by the percentage of lesions progressing in unsealed teeth. The prevented fraction and corresponding 95% CIs were obtained for each study by subtracting the RR and its corresponding CIs from 1.

Methods of synthesis

Results were combined in a meta analysis by calculating the median percentage of lesions progressing and the median prevented fraction for sealed and unsealed surfaces across all studies. The pooled RR with 95% CIs was calculated using the DerSimonian and Laird random-effects model. The data was adjusted for differences in study design, multiple observations per subject and 100 per cent or 0 per cent progression rates. The summary prevented fraction and corresponding 95% CI was calculated. Homogeneity was assessed using the I² statistic. Sensitivity analyses were conducted excluding cohort studies and assuming higher values of intra-oral correlation.

Results of the review

Six studies were included. The authors stated that they included an estimated 384 patients, 840 teeth and 1,090 surfaces (none of the studies appeared to report all three of these units). Four RCTs (approximately 140 patients) and one prospective and one retrospective cohort study were included. All studies were rated as fair on the validity assessment. One study had a high loss to follow up and three studies did not have blinded outcome assessment.

Caries progression in sealed lesions (median annualised progression rate 5 per cent) was lower than in unsealed lesions (median annualised progression rate 16.1 per cent). Sealing caries lesions reduced the likelihood of lesion progression by more than 70 per cent (summary prevented fraction was 73.2%, 95% CI 59.8 to 82.2 assuming perfect correlation between teeth or 75 per cent, 95% CI 67.1 to 81.1 assuming no correlation between teeth).

When only the RCTs were analysed, the summary prevented fraction remained above 70 per cent (four studies: summary prevented fraction 71.2%, 95% CI: 50.3, 83.3 assuming a correlation of 1). When only non-cavitated lesions were considered the median annualised progression rates for sealed lesions was 2.6% compared with 12.6% in unsealed lesions.

There was no evidence of statistical heterogeneity for any outcomes.

Authors' conclusions

Sealing non-cavitated caries in the pits and fissures of permanent teeth in children, adolescents and young adults was effective in reducing caries progression.

CRD commentary

The review addressed a clear question with well-defined inclusion criteria. Three relevant databases were searched, but only for studies published in English, which may have introduced language bias. No search for unpublished data appeared to have been carried out, therefore, publication bias could not be ruled out. Attempts were made to minimise reviewer errors and bias in some but not all parts of the review process, so reviewer error and bias cannot be ruled out. Study validity was assessed and results were discussed.

It was questionable whether pooling data from studies with different designs was appropriate for the main analysis. However, RCTs were analysed separately and generally provided similar results. Statistical heterogeneity was assessed and various sensitivity analyses were conducted.

The authors' conclusions reflected the results of the review, but the small number of studies and incomplete reporting of review methods undermined the robustness of the conclusions.

Implications of the review for practice and research

Practice: The authors stated that the placement of sealants in early or uncertain carious stages was supported. The low rates of progression for unsealed non-cavitated lesions meant that immediate surgical treatment of these lesions may not be necessary.

Research: The authors stated that further studies were needed that meet current standards in terms of design, conduct and reporting, particularly in cavitated lesions. Uniform criteria to assess the progression of cavitation and uniform methodologies to measure the progression of cavitation were needed.

Funding

Centers for Disease Control and Prevention

Bibliographic details

Griffin SO, Oong E, Kohn W, Vidakovic B, GoochB F, CDC Dental Sealant Systematic Review Work Group. The effectiveness of sealants in managing caries lesions. Journal of Dental Research 2008; 87(2): 169-174. [PubMed: 18218845]

Other publications of related interest

Oong EM, Griffin SO, Kohn WG, Gooch BF, Caufield PW. The effect of dental sealants on bacteria levels in caries lesions. A review of the evidence. JADA 2008;139:271-8.

Indexing Status

Subject indexing assigned by NLM

MeSH

Cohort Studies; Dental Caries /prevention & control; Disease Progression; Follow-Up Studies; Glass Ionomer Cements /therapeutic use; Humans; Models, Statistical; Pit and Fissure Sealants /therapeutic use; Probability; Randomized Controlled Trials as Topic; Resin Cements /therapeutic use; Time Factors; Treatment Outcome

AccessionNumber

12008102435

Database entry date

03/06/2009

Record Status

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.