Resin-modified glass-ionomer cements versus resin-based materials as fissure sealants: a meta-analysis of clinical trials.
Abstract: AIM: To appraise quantitatively current evidence regarding the caries-preventing effect of resin-modified glass-ionomer cement (RM-GIC) fissure sealants in comparison to that of resin-based fissure sealants. STIIDY DESIGN: Systematic review with meta-analysis. METHODS: 8 Anglophone databases and 2 Lusophone databases were searched until 15 April 2009, using a pre-determined search strategy. Clinical trials were considered for inclusion if their titles/abstracts were relevant to the topic, published in English, Portuguese or Spanish and had a two-arm longitudinal study design. The outcome measure of the caries-preventive effect was caries absence on sealed teeth. Two reviewers independently extracted data from the accepted articles in order to complete a 2 x 2 table for meta-analysis. The unit of interest was the tooth, and the number of caries-free teeth (n) at the end of each time interval (6, 12 and 24 months) was compared against the total number of evaluated teeth (N) STATISTICS: Datasets were assessed for their clinical and methodological heterogeneity, following Cochrane guidelines, and only homogeneous datasets were combined for meta-analysis, using a random effects model (RevMan 4.2). Differences in the caries-preventive effect were computed on the basis of the combined Relative Risk (RR) with 95% confidence interval (CI). RESULTS: Of the 212 articles identified, only 6 trials were included. From these, 19 separate datasets were extracted. For the pooled data, equivalent caries-preventive effects were observed at 6 months (RR = 0.98, 95% CI 0.95-1.00; p = 0.08); 12 months (RR = 1.00, 95% CI 0.96-1.04, p = 0.99) and 24 months (RR = 1.01, 95% CI 0.84-1.21, p = 0.91). The 36-month data (not pooled) favoured resin-based sealants (RR 0.93, 95% CI 0.88-0.97, p = 0.002) CONLUSIONS: This meta-analysis found no conclusive evidence that either material was superior to the other in preventing dental caries.

Key words: Resin-modified glass ionomers; resin; fissure sealant; meta-analysis
Article Type: Report
Subject: Dental caries (Care and treatment)
Dental caries (Research)
Pit and fissure sealants (Dentistry) (Health aspects)
Pit and fissure sealants (Dentistry) (Research)
Authors: Yengopal, V.
Mickenautsch, S.
Pub Date: 02/01/2010
Publication: Name: European Archives of Paediatric Dentistry Publisher: European Academy of Paediatric Dentistry Audience: Academic Format: Magazine/Journal Subject: Health Copyright: COPYRIGHT 2010 European Academy of Paediatric Dentistry ISSN: 1818-6300
Issue: Date: Feb, 2010 Source Volume: 11 Source Issue: 1
Topic: Event Code: 310 Science & research
Geographic: Geographic Scope: South Africa Geographic Code: 6SOUT South Africa
Accession Number: 277106713
Full Text: Introduction

Use of pit and fissure sealants (FS) has become accepted as an effective intervention for the prevention of occlusal caries in the molar teeth of young children [Kitchens, 2005; Ahovuo-Saloranta et al., 2008]. The evidence for the clinical efficacy and cost-effectiveness of FS in reducing occlusal caries in molars has been highlighted in recent papers [Kitchens, 2005; Ahovuo-Saloranta et al., 2008]. Resin-based FS materials are most commonly used and are regarded as the 'gold standard' for sealing pits and fissures [Adair, 2003]. Their caries- preventive effect relies on the sealing of pits and fissures through micro-retention, created through tags after acid etching of enamel. However, these are easily destroyed by saliva contamination, reducing micro-retention and consequently, the caries-preventive effect [Bishara et al., 2002]. Moreover, the preventive benefits and resin-based FS retention are gained and maintained only as long as the sealants remain completely intact and bonded in place [Oliveira et al., 2008].

Under clinical conditions, it is difficult to maintain an absolutely dry environment in the oral cavity in which to place resin-based FS especially in uncooperative children and in settings where isolation is rarely possible and where equipment such as rubber dam and dental suction is not readily available. Under the generally wet conditions in the oral cavity, glass-ionomer cement (GIC) FS offer an effective alternative to resin sealants, mainly because they have hydrophilic properties [Smith, 1998].

The original glass-ionomer cements, set through an acid-base reaction, between the fluoroaluminosilicate glass powder and the polyalkenoic acid liquid, are generally regarded as 'conventional' glass-ionomers (C-GIC). However, C-GICs are sensitive to water uptake and loss in the first hours or days after setting, and this led to the development of 'resin-modified' GICs (RM-GIC) which, in the set material, contain approximately 10% of resin, usually hydroxyethylmethacrylate (HEMA) [Ikeda et al., 1999].

It has been suggested that the 'gold standard' in caries prevention through FS administration should be based on biological outcomes rather than physical (material retention on the tooth surface) ones [Smith, 1998]. Such biological outcomes are measured in relation to the absence of caries in pits and fissures after FS application. A recent meta-analysis [Yengopal et al., 2009] that assessed biological outcomes found evidence that neither (low-viscosity) C-GIC nor resin-based FS was superior to the other in the prevention of dental caries. To date, no systematic review of the topic of caries-preventive effects of RM-GIC versus resin-based FS has been attempted. Thus, the aim of this systematic review with meta-analysis was to appraise quantitatively the current evidence regarding the caries-preventing effect of RM-GIC fissure sealants in comparison to that of resin-based fissure sealants.

Materials and Methods

Search strategy. The literature search covered 8 Anglophone databases: Biomed Central, Cochrane Oral Health Reviews, Cochrane Library, Directory Of Open Access Journals, Expanded Academic ASAP PLUS, Meta Register Of Controlled Trials--mRCT, PubMed, Science-Direct, and 2 Lusophone databases: Bibliografia Brasileira Em Odontologia - BBO, Literatura Latino-Americana E Caribenha Em Ciencias Da Saude--LILACS.

In order to search databases, strings of search terms were constructed, consisting of relevant text words and Boolean links and MeSH words. The string of English search terms: 'Pit and Fissure Sealants'[Mesh] and 'Glass Ionomer Cements'[Mesh] and 'resin modified glass ionomer' and 'fissure sealant*' was used to search the Anglophone databases and the string of Portuguese search terms: 'selante' [palavras] and 'cimentos de ionomeros de vidro' [palavras] and 'CARIE' [Palavras]' was used to search the Lusophone databases. Related words in Spanish were used for LILACS. All publications listed in the databases until 15 April 2009 were included in the search.

Inclusion and exclusion criteria. Articles reporting on clinical trials were selected for review from the search results on the basis of their compliance with the inclusion criteria:

* Titles/abstracts relevant to topic;

* Published in English, Portuguese or Spanish;

* Two-arm longitudinal study design.

Where only a relevant title without a listed abstract was available, a full copy of the article was assessed for inclusion. A reference check of the included articles was conducted in order to identify further trials suitable for inclusion.

Only articles that complied with the inclusion criteria were reviewed further. Full copies of articles were reviewed independently by two reviewers (VY, SM), using the exclusion criteria [Sutherland, 2001]:

* No random or quasi-random allocation of study subjects;

* Not all entered subjects accounted for at the end of the trial;

* Subjects of both groups not followed up the same way;

* No computable data reported for both control (comparison) and test groups;

* No in-vivo study design.

Where several articles had reported on the same trial over similar time periods, the article covering the trial most comprehensively in accordance with the exclusion criteria was accepted. Disagreements between reviewers were resolved by discussion and consensus.

Quality Assessment. The quality assessment of the included trials was undertaken independently by two reviewers (VY, SM) and followed established guidelines [Juni et al., 2001; The Grade working group, 2004]. Trials not included in this review were used in piloting the quality assessment process. Disagreements between the reviewers regarding quality assessment ratings scored were resolved through discussion and consensus. Four main quality criteria were examined:

(1) Generation of randomisation sequence (Allocation), recorded as:

(A) Adequate--e.g. computer generated random numbers, table of random numbers; (B) Unclear; (C) Inadequate--e.g. case record number, date of birth, date of administration, alternation;

(2) Allocation concealment, recorded as:

(A) Adequate--e.g. central randomisation, sequentially numbered sealed opaque envelopes; (B) Unclear; (C) Inadequate--e.g. open allocation schedule, unsealed or non-opaque envelopes;

(3) Blind outcome assessment, recorded as:

(A) Yes; (B) Unclear; (C) No; (D) Not used/possible;

(4) Completeness of follow-up (clear explanation for withdrawals and loss-to-follow-up in each treatment group), assessed as:

(A) Yes, drop outs less than 30%; (B) Yes, drop outs more than 30% ; (C) No explanation.

Data extraction from accepted trials. The outcome measure of the caries-preventive effect was the caries absence on sealed teeth. The two reviewers independently extracted data from the accepted articles, using a pilot-tested data-extraction form. Data were extracted in the form of datasets with common characteristics (Table 2). Each dataset included the number of caries-free teeth (n) and total number of evaluated teeth (N) for both the control (comparison) and the test group. Where possible, missing data were calculated from information given in the tables and texts of the articles, in order to complete a 2x2 table for meta analysis. Disagreements between reviewers during data extraction were resolved through discussion and consensus.

It was anticipated that some of the studies eligible for inclusion would be split-mouth in design. The split-mouth study design is commonly used in dentistry to test interventions and has the advantage of having an individual serve as both experiment and control. In this study design, one or more pairs of teeth (e.g. primary molars) form the unit of randomisation. Strictly speaking, these pairs are not independent and should be analysed as 'paired data' on a patient basis. However, as in other systematic reviews where split-mouth trials are included [Ahovuo-Saloranta et al., 2008], the decision was to analyse the pairs independently in order to avoid the exclusion of trials that were directly related to the research question.

Meta-analysis. Datasets were assessed for their clinical and methodological heterogeneity, following Cochrane guidelines [The Cochrane Collaboration, 2006]. Datasets were considered homogenous if they did not differ substantially in the following clinical and methodological aspects: age of patients; follow-up period; type of FS material used; frequency of FS material application; measured outcome. The percentage of total variations across datasets ([I.sup.2]) and the associated p-value (<0.10) were used in assessing statistical heterogeneity [Thompson, 1994]. Only identified homogeneous datasets from included trials (clinical and methodological homogeneity) were combined for meta-analysis, for which the random effects model of the meta-analysis software, RevMan 4.2 was used. The differences in the caries-preventive effect were computed on basis of the combined Relative Risk (RR) with 95% confidence interval (CI). Datasets were assigned a Mantel-Haenszel weight in direct proportion to sample size. For datasets that were not suitable for meta-analysis, due to aspects related to clinical and methodological heterogeneity, RR scores with 95% CI were calculated for each dataset and reported separately.

Results

An initial search in PubMed resulted in 212 articles, of which 8 trials [Raadal et al., 1996; Kilpatrick et al., 1996; Winkler et al., 1996; Tantbirojn et al., 1997; Smales and Wong, 1999; Pardi et al., 2005; Kantovitz et al., 2006; Oliveira et al., 2008] complied with the inclusion criteria. A reference check and a subsequent search of the other 7 Anglophone databases and the 2 Lusophone databases generated no further results. Two the 8 articles [Tantbirojn et al., 1997; Kantovitz et al., 2006] were excluded because they reported on in-vitro trials. Hence only 6 articles [Raadal et al., 1996; Kilpatrick et al., 1996; Winkler et al., 1996; Smales and Wong, 1999; Pardi et al., 2005; Oliveira et al., 2008] were accepted for quality assessment and further data extraction.

Quality assessment and Data extraction of accepted articles. Table 1 presents data on the quality assessment of the included trials. All trials scored 'B' (unclear) for Randomized sequence allocation, and Allocation concealment, owing to lack of clear information in the text, 'D' (not possible for Blinding), and 'A' (adequate) for completeness of follow-up.

From the 6 accepted articles, 19 separate computable dichotomous datasets with relevance to the review question were extracted. The main clinical and methodological characteristics of the extracted datasets are described in Table 2. The reason for separating the data in this format was the need for avoidance of clinical and/or methodological heterogeneity. Additionally, this allowed for the identification of homogenous datasets, which then could be pooled together for meta-analysis. Considerable variation existed among the datasets in terms of most of the items reported in Table 2. This had an impact upon determining whether the compiled datasets could be pooled for the meta-analyses reported in Figures 1-3. The dataset # 17, extracted from the trial by Kilpatrick et al. [1996], could not be pooled with any of the other datasets because FS were placed on permanent premolar teeth, as opposed to permanent molar teeth in all of the other datasets. In addition, the reporting times, patient characteristics, methods of application and other variables also differed and these factors were considered during compilation of the 19 datasets extracted from the 6 accepted trials (Table 2).

Pooling of data for meta-analyses. Only datasets that were considered clinically and methodologically homogenous were pooled for meta-analysis. The unit of interest was the tooth and the number of caries-free teeth (n) at the end of each time interval (6, 12 and 24 months) was compared against the total number of evaluated teeth (N). Datasets from three trials [Raadal et al., 1996; Winkler et al., 1996; Oliveira et al., 2008] were pooled for the 6-month evaluation (Figure 1). The pooled data covered 491 teeth (227 resin-modified glass-ionomer FS and 264 resin FS). The pooled relative risk (0.98, 95% CI 0.95-1.00; p = 0.08) suggests that both materials had an equivalent caries-preventive effect at 6 months post-placement.

Datasets from 4 trials [Raadal et al., 1996; Winkler et al., 1996; Pardi et al., 2005; Oliveira et al., 2008] were pooled for the 12-month evaluation (Figure 2). The pooled data covered 719 teeth (341 resin-modified glass-ionomer FS and 378 resin FS) and the pooled relative risk (1.00, 95% CI 0.96-1.04, p = 0.99) also implied equivalent caries-preventive effects at 12 months post placement. Similar results were obtained for the 24-month evaluation (Figure 3, RR 1.01, 95% CI 0.84-1.21, p = 0.91). Only one dataset (#16) was available for comparison at 36 months [Raadal et al., 1996]: thus no meta-analysis was attempted. The results (RR 0.93, 95% CI 0.88-0.97, p = 0.002) indicate that teeth sealed with resin-based FS have a 7% higher chance than those sealed with RM-GIC sealants, of remaining caries-free after 36 months.

A further 7 datasets could also not be included in the meta-analyses, due to aspects related to clinical and methodological heterogeneity (Table 3). Of these, none showed any difference in caries absence between teeth sealed with RM-GIC or resin-based materials after 1-, 6-, 12-, 24- or 27 months.

Discussion

This systematic review with meta-analyses sought to quantitatively appraise the current evidence regarding the caries-preventing effect of RM-GIC FS in comparison to that of resin-based FS over varying time intervals. Of the more than 200 articles identified through the search strategy for this review, only 6 were included. The quality assessment of these trials (Table 1) warrants that the data be treated with caution, owing to an increased risk of bias. All of the included papers scored 'B' (unclear) for an important quality item dealing with two key aspects of selection bias: randomised sequence allocation and allocation concealment. Such bias or systematic error may affect studies by causing either an over- or an under-estimation of the treatment effect of an investigated clinical procedure. Overestimation of such effect has been observed to be the most common [Chalmers et al., 1977]. Schulz et al., [1995] reported a 41% treatment effect overestimation due to selection bias, caused by lack of allocation concealment during the randomisation process alone. As all trials accepted in this review did not include or report on allocation concealment, their results need to be interpreted with caution. Thus, for systematic reviews, readers should note that while in terms of the hierarchy of evidence [Sprague et al., 2008] this form of study design is rated the highest, the level of evidence contained in such a review is only as high as that of the studies that it covers.

Meta-analysis of homogeneous datasets at three time intervals (Figures 1-3) showed no statistical differences between RM-GIC and resin-based FS, in caries absence. The results of 7 further heterogeneous datasets (#01, 03, 05, 07, 11, 12, and 17) are in line with the meta-analysis findings (Table 3). At 36 months (dataset #16), the resin-based FS performed, by a margin of 7%, significantly better (RR 0.93, 95% CI 0.88-0.97, p = 0.002) than RM-GIC. However, caution is warranted as the data were drawn from a study with a high risk of bias [Raadal et al., 1996].

Previous publications [Forss and Halme, 1998; Mejare et al., 2003; Ahovuo-Saloranta et al., 2008] have highlighted a number of factors that could potentially affect the caries-preventive effect of FS. Only some of the trials reported on these factors. They include: (a) baseline caries prevalence in the study population (none of the included trials reported on this); (b) number of applications of FS material--single or repeated (all trials reported single application); (c) type of FS material (all included trials); (d) follow-up period (all included trials); (e) type of tooth and location in jaw (reported only by Raadal et al., 1996); (f) fluoride content of drinking water (none); (g) operator factors (one trial [Oliveira et al., 2008]); (h) role of other simultaneous preventive measures, e.g., topical fluoride application (none); and (i) frequency of eating sugary snacks (none).

The appropriateness of some of the outcomes reported, especially in the RM-GIC trials, should be noted, as these FS are effective long after being regarded as 'lost' or 'partially lost' [Songpaisan et al., 1995, Williams et al., 1996].

It has been hypothesized that although the GIC sealants appear clinically as 'partially' or 'totally' lost, the opening of the fissures remains sealed [Oong et al., 2008]. In addition, the effectiveness of GIC has been attributed to the isolation of bacteria from nutrients in sealed lesions; the release of fluoride into the dentine or a combination of both factors [Oong et al., 2008]. In contrast, resin-based FS have been shown to lose almost all of their protective effect once their retention is lost [Beiruti et al., 2006]. Hence, the measured outcome of interest when comparing RM-GIC and resin-based FS should be caries incidence/increment or caries presence/ absence rather than retention of the sealant material.

The meta-analyses presented in Figures 1-3 used a random effects model. This model is recommended over a fixed-effect model when heterogeneity is suspected; even after qualitative assessment for clinical and methodological heterogeneity suggests that the data from different trials could be pooled together [Higgins et al., 2003]. This usually is the case in trials having large variations in the size and direction of the treatment effect. After the pooled result is obtained and reflected in the form of a forest plot (Figures 1-3), statistical heterogeneity needs to be assessed [Higgins et al., 2003]. If this occurs (usually reflected as a high I2 value above 75%) and a significant p-value (below 0.10), then a suitable explanation is required as to whether genuine clinical or methodological differences exist between the pooled datasets. In the case of Figure 3, the statistical heterogeneity (I2 = 85.1%, p = 0.009) can be explained by the inconsistency in the observed treatment effect across the two datasets. The Raadal et al. [1996] trial found slightly in favour of the resin-based FS, whilst the trial by Pardi et al. [2005] favoured RM-GIC FS for the same outcome (Figure 3). For Figure 1, the test for heterogeneity did not apply, as the pooled result comprised results from only one estimable dataset. The result of a dataset is regarded as 'not estimable' when data (n/N) from the test- and the control group are identical, with a subsequent Relative Risk (RR) of 1.00. Figure 2 reflects a moderate I2 value (48.3%), with a p-value of 0.12 that suggests little variation in the size and direction of the treatment effect across pooled datasets.

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Conclusion

This systematic review with meta-analysis found no evidence that either material was superior to the other in preventing dental caries. Therefore, both materials appear to be equally suitable for clinical application as FS for a period of up to 2 years. However, the poor quality of the included trials warrants that further high-quality randomised control trials are needed to obtain conclusive evidence of equivalence or difference in caries prevention. Further trials should also investigate the long-term caries preventive effect of both materials beyond the period of 2 years. Trial reporting should follow the CONSORT statement [Moher et al., 2001] and, particularly, include a clear description of how the randomised allocation of study subjects to test- and control groups was conducted; state who generated the allocation sequence, who enrolled the subjects and who assigned subjects to their groups. Reporting should further include information about whether such allocation was concealed from the clinical operators until interventions were assigned and, if it was, about how such concealment was done. Reports should indicate, where possible, whether assessment of the treatment outcome was conducted by evaluators who were blinded to allocation of the study subjects into groups and also discuss details of any possible confounding factors with potential influence on the observed treatment effect.

Acknowledgement

The authors like to thank Dr Luciana Oliveira from the Sao Leopoldo Mandic Research Center, Campinas, Sao Paulo, Brazil for conducting the literature search in the Lusophone databases.

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V. Yengopal, S. Mickenautsch

Division of Public Oral Health, University of the Witwatersrand Johannesburg, South Africa

Postal address: Dr S Mickenautsch. Division of Public Oral Health, University of the Witwatersrand, 7 York Rd., Parktown/Johannesburg, 2193, South Africa

Email: neem@global.co.za
Table 1. Quality assessment of included trials comparing resin-
modified glass-ionomer cements versus resin-based materials as
fissure sealants.

                                 Selection bias        Detection
                                                         bias

Article                       Random     Allocation    Evaluator
                            allocation   concealment   Blinding

Oliveira et al., 2008           B             B            D

Pardi et al., 2005              B             B            D

Smalles and Wong, 1999          B             B            D

Raadal et al., 1996             B             B            D

Kilpatrick et al., 1996         B             B            D

Winkler et al., 1996            B             B            D

Article                     Completeness
                            to follow-up

Oliveira et al., 2008       A (start n = 108; 6 months n = 98;
                            12 months n = 88)

Pardi et al., 2005          A (at start 356 teeth; end n = 329

Smalles and Wong, 1999      A (start n = 14; end n = 14)

Raadal et al., 1996         A (start n = 53; end n = 53)

Kilpatrick et al., 1996     A (start n = 76; end n = 58)

Winkler et al., 1996        A (start n = 50; 6 months n = 43;
                            12 months n = 40

n = Number of patients.

Table 2. Characteristics of data sets (DS) with potential influence
on study outcome--Part I.

Article        DS      2-arm          Test           Control
                       study          material       material
                       design         (RM-GIC)       (Resin-
                                                     based)

Oliveira et    01      PG--I          Vitremer       Delton
al., 2008      02
               03
               04
               05
               06
               07
               08

Pardi et       09      PG--I          Vitremer       Revolution
al., 2005      10

Smales and     11      Not            K-512 (Fuji    Delton
Wong, 1999             reported       III LC)

Raadal et      12      SG             Vitrebond      Concise
al., 1996      13
               14
               15
               16

Kilpatrick     17      PG--II         Vitrebond      Concise
et al., 1996

Winkler et     18      SG             Fuji II LC     Concise
al., 1996      19

Article        DS           Outcome measure          Patient /
                                                     age, gender
                       Aspect         Definition

Oliveira et    01      Caries         No softness,   Age: Mean
al., 2008      02      absence        no opacity,    7.5 (SD
               03                     no etch on     1.25) years,
               04                     enamel         Range 5-10
               05                                    years
               06                                    Gender: no
               07                                    info
               08

Pardi et       09      Caries         No visible     Age: 7-8
al., 2005      10      absence        caries'        years
                                                     Gender: no
                                                     info

Smales and     11      Caries         No softness,   Age: Mean 22
Wong, 1999             absence        no opacity,    years, Range
                                      no etch on     15-27 years
                                      enamel
                                                     Gender: 12
                                                     female/7
                                                     male

Raadal et      12      Caries         Caries         Age: Range
al., 1996      13      absence        diagnostic     5-7 and 11-
               14                     criteria by    13 years
               15                     Moller,
               16                     Grades '0'     Gender: 29
                                      and '1'        female/24
                                                     male

Kilpatrick     17      Caries         Caries         Pediatric
et al., 1996           absence        absent'        patients
                                                     and older
                                                     patients
                                                     with
                                                     learning
                                                     difficulties
                                                     or
                                                     development
                                                     delays

Winkler et     18      Caries         No softness,   Age: Range
al., 1996      19      absence        no opacity,    7-10 and
                                      no etch on     years
                                      enamel

                                                     Gender: no
                                                     info

Article        DS      Dentition      Type of        Follow-up
                                      tooth          period

Oliveira et    01      Permanent      1st Molar      6 months
al., 2008      02                     teeth          12 months
               03
               04
               05
               06
               07
               08

Pardi et       09      Permanent      1st Molar      12 months
al., 2005      10                     teeth          24 months

Smales and     11      Permanent      No info        24 months
Wong, 1999

Raadal et      12      Permanent      1st/2nd        1 months
al., 1996      13                     Molars 1       6 months
               14                     month          12 months
               15                                    24 months
               16                                    36 months

Kilpatrick     17      Permanent      Premolar       27 months
et al., 1996                          teeth

Winkler et     18      Permanent      1st Molar      6 months
al., 1996      19                     teeth          12 months

PG-I = Parallel group design with patients as unit of investigation;
PG-II = Parallel group design with sealed teeth as unit of
investigation; SG = Splitmouth design; SD = Standard deviation.

Table 2. Characteristics of data sets (DS) with potential influence
on study outcome--Part II.

Article         DS     Caries         Fluoride       RM-GIC
                       activity,      exposure       powder/
                       risk or                       liquid
                       preva-                        mixture
                       lence                         (Ratio)

Oliveira        01     Groups         No info        0.25 : 1
                       matched per
                       dmft/ DMFT
et al., 2008    02                                   1 : 1

                                                     0.25 : 1
                03

                                                     1 : 1
                04

                                                     0.25 : 1
                05

                                                     1 : 1
                06

                                                     0.25 : 1
                07

                                                     1 : 1
                08

Pardi et        09     Caries free    No info        1 : 2
al., 2005       10     teeth

Smales and      11     No info        No info        No info
Wong, 1999

Raadal et       12     Caries free    No info        No info
al., 1996
                13     teeth

                14

                15

                16

Kilpatrick      17     Teeth with     No info        No info
et al., 1996           early
                       carious
                       lesions

Winkler et      18     Caries free    No info        No info
al., 1996       19     teeth

Article         DS     Moisture control

Oliveira        01     Delton applied under moisture control with
                       rubber dam

et al., 2008    02     Delton applied under moisture control with
                       rubber dam

                       Delton applied under moisture control with
                03     cotton wool rolls

                       Delton applied under moisture control with
                04     cotton wool rolls

                       Delton applied under moisture control with
                05     rubber dam

                       Delton applied under moisture control with
                06     rubber dam

                       Delton applied under moisture control with
                07     cotton wool rolls

                       Delton applied under moisture control with
                08     cotton wool rolls

Pardi et        09     Moisture control with cotton wool rolls
al., 2005       10

Smales and      11     No info
Wong, 1999

Raadal et       12     Moisture control with cotton wool rolls
al., 1996
                13

                14

                15

                16

Kilpatrick      17     Moisture control with cotton wool rolls
et al., 1996           or rubber dam

Winkler et      18     Moisture control with cotton wool rolls
                       or rubber dam
al., 1996       19

Article         DS     Material       Process of     Presentation
                       re-appli-      outcome        of results
                       cation         measure-
                                      ment

Oliveira        01     No             Clinical       In
                                      examination    percentages,
                                                     number of
et al., 2008    02                                   teeth
                                                     calculated
                                                     by hand

                03

                04

                05

                06

                07

                08

Pardi et        09     No             Clinical       Number of
al., 2005       10                    examination    teeth
                                                     reported

Smales and      11     No             Bitewing       Number of
Wong, 1999                            radiographs    teeth
                                                     reported

Raadal et       12     No             Clinical       Number of
al., 1996                             examination,   teeth
                13                    bitewing       reported
                                      radiographs
                14

                15

                16

Kilpatrick      17     Yes            Clinical       Number of
et al., 1996                          examination    teeth
                                                     reported

Winkler et      18     No             Clinical       Number of
al., 1996       19                    examination    teeth
                                                     reported

Table 3. Results of datasets not included in the meta-analyses.

Article                     DS        RM-GIC           Resin

                                     n       N       n       N

Oliveira et al., 2008       01      51      51      34      34
                            03      51      51      51      51
                            05      51      51      34      34
                            07      51      51      48      51

Smales and Wong, 1999       11      46      47      38      41

Raadal et al., 1996         12      136     136     136     136
                            16      126     136     136     136

Kilpatrick et al., 1996     17      66      66      66      66

Article                     DS      RR         95%CI         p-value

Oliveira et al., 2008       01     1.00          =              =
                            03     1.00          =              =
                            05     1.00          =              =
                            07     1.06      0.98, 1.15        0.13

Smales and Wong, 1999       11     1.06      0.96, 1.16        0.26

Raadal et al., 1996         12     1.00          =              =
                            16     0.93     0.88, 0.97 *     0.002 *

Kilpatrick et al., 1996     17     1.00          =              =

DS = Dataset number; RM-GIC = Resin-modified glass-ionomer cement;
Resin = Resin-based material; n = number of caries free sealed
teeth; N = Total number of sealed teeth evaluated; RR = Relative
risk; CI = Confidence interval; * Statistically significant
difference in favour of resin.
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