Clinical effectiveness and cost-effectiveness of fissure sealants in children and adolescents with a high caries risk.

In Germany, the application of resin-based pits and fissures sealants on the occlusal surfaces of permanent molars is part of individual prophylaxis for children and adolescents between six and 18 years. The individual prophylaxis is covered by the Statutory Health Insurance since 1993. The report addresses questions on medical effectiveness, cost-effectiveness, as well as ethical, social, and legal implications of pit and fissure sealants in preventing dental caries for children and adolescents at high caries risk. The results of the studies indicate a protective effect of pit and fissure sealants, particularly for children and adolescents at high caries risk. Additionally, the economic evaluation suggests a tendency for cost savings in this group. Nevertheless, a general expansion of the intervention cannot be recommended. All studies show a risk of bias in favour of pit and fissure sealing and a limited transferability to the German health care system. Studies included in the economic evaluation revealed methodological flaws. Both the economic models and primary studies do not provide reliable results.

Summary

Scientific background

Dental caries is a multifactorial disease. Diet and the bacteria in the dental plaque play an essential role in the development of caries. Interventions targeting at children are considered to be very effective. Since the late 1980s there has been a decrease of DMFT for school age children in Germany. The DMFT of twelve-year-old children fell from 4.1 in the former Federal Republic of Germany (West Germany) and 3.8 in the German Democratic Republic in 1989 (East Germany) to 0.7 in (reunited) Germany in 2009. But there is a polarisation of dental caries: For the majority of children and adolescents there has been a strong decline in caries rates but a concentration of high rates of dental caries in small groups of children (e.g. children with migration background).

Sealing pits and fissures of teeth is a tooth-specific intervention. A flowable material is applied to the susceptible occlusal surfaces of the molars to prevent the development of dental caries or to stop the progression of initial caries in dental enamel. It is an additional intervention to reduce the caries risk, which supplements preventive measures aiming at the whole dentition (e.g. tooth brushing). In Germany, sealing the occlusal pits and fissures of permanent molars (first and second molar) with resin-based sealing material is part of the individual prophylaxis for children and adolescents between six and 18 years. The costs for the application of pit and fissure sealing are covered by the Statutory Health Insurance since 1993 (IP-Position 5). Individual prophylaxis takes place in dental offices. It was introduced to supplement group prophylaxis which visits children at the kindergarten or at school. It includes preventive measures as oral education and the control of the dentition.

The efficacy of pit and fissure sealants has been extensively studied. The application is very wide spread. It is believed to be effective but this is mostly based on trials from the 1970ies and the 1980ies. In addition, evidence on the effectiveness of this intervention among children at different levels of caries risk is still lacking.

The costs of pits and fissure sealants amount to 14 to 16 Euro per tooth for children in the German Statutory Health Insurance. In total, 66 Million Euro were spent by the German Statutory Health Insurance for pit and fissure sealants in 2011. This adds up to about 17% of the costs for the individual prophylaxis. International studies examining the cost-effectiveness of pits and fissure sealants have shown inconsistent results. There is no comprehensive analysis of the cost- effectiveness in Germany.

Research questions

Medical evaluation

Do children and adolescents, who received pit and fissure sealants in their permanent molars show lower caries rates than those:

who did not receive pit and fissure sealants in their permanent molars?

who received a professional application of fluoride varnish on their permanent molars?

Do children and adolescents at high caries risk, who received pit and fissure sealants in their permanent molars show lower caries rates than those:

who did not receive pit and fissure sealants in their permanent molars?

who received fluoride varnish professionally applied on their permanent molars?

Economic evaluation

Are pit and fissure sealings cost-effective compared to no sealing or the application of fluoride varnish in populations of children at high caries risk?

What are the effects on the costs of dental care for children and adolescents at high caries risk (instead of no sealing or the application of fluoride varnish)?

Does the application of pit and fissure sealants lead to reductions in costs for dental care in populations of children and adolescents at high caries risk?

Further, the health economic evaluation includes an examination of the transferability to the German health care context.

Ethical, social and legal implications

Do studies identified by the systematic literature search report on factors affecting the utilisation of pit and fissure sealants by different groups (e.g. children with migration background)?

Are there any controlled trials examining interventions to improve utilisation of pit and fissure sealing of children and adolescents with low socioeconomic status and/or migration background?

Do studies included in the medical evaluation report on local or systematic side effects or adverse reactions of pit and fissure sealants?

Methods

A systematic literature search in 34 electronic databases was conducted in May 2012 to evaluate medical effectiveness, cost-efficiency and to identify ethical, social and legal aspects of the utilisation of pit and fissure sealants. The search included the languages English, German and French and was not confined to a certain period of time.

In a first step, the titles and abstracts of identified publications were screened according to predefined selection criteria. In a second step, the selected publications were examined as a whole. Two independent reviewers did the selection of the literature. The methodological quality of included publications was assessed using extraction sheets specifically prepared for each research question.

Medical evaluation

The search identified 1,249 publications for the medical evaluation of pit and fissure sealants. In total, 104 publications were considered as potentially relevant. They were acquired in full text by DAHTA.

A total of 19 randomised or quasi-randomised controlled trials (RCT) and systematic reviews met the inclusion criteria and was assessed in detail: 15 RCT and four systematic reviews. The RCT were designed as parallel group (eight studies) or as split-mouth studies (seven studies). Most of the trials (14 studies) examined the effectiveness of sealing permanent molars compared to a control group without fissure sealants. Three trials compared pit and fissure sealants to the professional application of fluoride varnish. Information on children and adolescents at high caries risk was reported in seven trials. The comparison of pit and fissure sealants versus a control group without fissure sealants was done in three systematic reviews. The other systematic reviews compared pit and fissure sealants versus professional application of fluoride varnish.

All RCT were affected by the risk of bias in favour of pit and fissure sealants (e.g. selection bias, detection bias) and were thus graded as 1– according to the quality criteria. However, the attempts to control bias were heterogeneous. Efforts to control bias (e.g. by blinding of outcome evaluation) were made by three parallel groups and two old split-mouth design RCT. A severe risk of bias (e.g. different selection criteria for intervention and control groups) and poor reporting quality was found in three further parallel groups and the remaining split-mouth RCT. Furthermore, the studies reviewed included populations of children and adolescents showing heterogeneous socioeconomic and cultural backgrounds and they took place in various settings such as Thailand and Australia. Thus, the comparability and transferability of results is limited. One of the four systematic reviews applied quality criteria to the identified studies comparable to the ones we used, and arrives at a comparable assessment of the quality of evidence. Two other reviews used less rigorous criteria and classified the available evidence as good. The fourth review did not provide information on this issue.

The studies and literature reviews have shown protective effects of pit and fissure sealants compared to no sealants and compared to the professional application of fluorides. This has been the case especially for children and adolescents at high caries risk. However, because of methodological flaws, the results of the RCT should be interpreted with caution.

Health economic evaluation

The economic literature search identified 263 publications. In total, 63 publications were considered as potentially relevant. They were obtained in full text by DAHTA.

A total of 14 records was included and assessed in detail: one systematic review, eight prospective or retrospective studies and five economic models. The economic models indicate cost savings for the sealing of the pit and fissures of children and adolescents at high caries risk. The prospective and retrospective studies reveal heterogeneous results. However, studies and economic models suggest cost savings at longer duration of follow-up periods.

Due to methodological flaws the results of the prospective or retrospective studies and economic models should be interpreted with caution. The evidence on the cost-effectiveness of pit and fissure sealants is insufficient. As there is insufficient evidence, an estimation of the effects of this intervention on costs of further dental care is not possible. Therefore, it is not possible to examine the transferability to the German health care context.

Ethical, social and legal implications

In total, 39 publications were identified and ordered in full text. None of the publications addressed relevant aspects. No publications reported on factors affecting the utilisation of pit and fissure sealants in different groups (e.g. children with migration background). No controlled trials have been identified that examined caries preventive interventions for children and adolescents with low socioeconomic status and/or migration background.

Side effects are addressed by three of the 15 RCT. All three reported that no allergic reactions have occurred during the trial.

Discussion

The medical evaluation shows protective effects of pit and fissure sealants in children and adolescents at high caries risk. These results are confirmed by the included systematic reviews. However, because all studies show bias in favour of pit and fissure sealants, the results of the RCT should be interpreted with caution. Additionally, since studies took place in different institutional, social and cultural settings the transferability to the German health care system is limited.

The economic evaluation suggests cost savings in children and adolescents at high caries risk with a longer duration of the follow-up period. However, due to methodological flaws the evidence on the cost-effectiveness of pit and fissure sealants is insufficient.

The systematic assessment of the effectiveness of pit and fissure sealants revealed multiple methodological flaws and information gaps in the included publications:

Many studies show poor reporting quality.

The studies apply heterogeneous definitions for children and adolescents at high caries risk. Additionally, the studies were performed in various settings and included samples with a heterogeneous socioeconomic and cultural background. Thus, the comparability and transferability of results are limited.

All studies considered in the medical evaluation revealed bias in favour of pit and fissure sealants (e.g. selection bias, detection bias).

Due to methodological flaws the results of the prospective and retrospective studies as well as the economic models should be interpreted with caution.

The publications included in the economic evaluation use heterogeneous outcomes. This indicates the lack of consensus on primary outcomes suitable for economic evaluation and reduces the assessment merely to the question of cost savings.

For a comprehensive assessment of the medical effectiveness and cost-efficiency of pit and fissure sealants in children and adolescents at high caries risk adequate studies at high methodological quality in a transferable setting are needed. Additionally, there is a need for discussions on appropriate health outcome for economic evaluation besides mere cost savings. The studies considered in the medical evaluation recruited their participants at schools. The transferability of these effects to the German health care system might be limited. Since pit and fissure sealants as part of the individual prophylaxis is given in dental offices, it might be more difficult to obtain a comparable number of children and adolescents with an insufficient utilisation of dental check-ups. The visiting concept of the group prophylaxis might be a starting point. The further development and reorientation of the individual and the group prophylaxis might provide an improvement in the caries prevention in children and adolescents with an insufficient utilisation of dental check-ups.

Conclusion

The results of the studies indicate a protective effect of pit and fissure sealants, particularly for children and adolescents at high caries risk. Additionally, the economic evaluation suggests a tendency for cost savings in this group. Nevertheless, a general expansion of the intervention cannot be recommended. All studies show a risk of bias in favour of pit and fissure sealing and a limited transferability to the German health care system. Studies included in the economic evaluation revealed methodological flaws. Both the economic models and primary studies do not provide reliable results.

However, there is a concentration of high rates of dental caries in the group of children and adolescents with high caries risk. Thus additional preventive interventions seem necessary and suitable measures of the German “Individualprophylaxe” and “Gruppenprophylaxe” should be evaluated. To estimate the effectiveness of pit and fissure sealants in children and adolescents with high caries risk in Germany, a study of high methodological quality in Germany or a country with comparable social, cultural and institutional structures is needed. Assuming the effectiveness of the pit and fissure sealants a next step should be to evaluate the reachability of children and adolescents at high risk and the utilization of pit and fissure sealants by this group.

Notes

Competing interests

The authors declare that they have no competing interests.