Open Access
Open Peer Review

This article has Open Peer Review reports available.

How does Open Peer Review work?

Methodological quality and implications for practice of systematic Cochrane reviews in pediatric oral health: a critical assessment

  • Violaine Smaïl-Faugeron1, 2, 3Email author,
  • Hélène Fron-Chabouis3, 4 and
  • Frédéric Courson2, 3
BMC Oral Health201414:35

DOI: 10.1186/1472-6831-14-35

Received: 19 December 2013

Accepted: 31 March 2014

Published: 9 April 2014

Abstract

Background

To ensure evidence-based decision-making in pediatric oral health, Cochrane systematic reviews that address topics pertinent to this field are necessary. We aimed to identify all systematic reviews of paediatric dentistry and oral health by the Cochrane Oral Health Group (COHG), summarize their characteristics and assess their methodological quality. Our second objective was to assess implications for practice in the review conclusions and provide an overview of clinical implications about the usefulness of paediatric oral health interventions in practice.

Methods

We conducted a methodological survey including all paediatric dentistry reviews from the COHG. We extracted data on characteristics of included reviews, then assessed the methodological quality using a validated 11-item quality assessment tool (AMSTAR). Finally, we coded each review to indicate whether its authors concluded that an intervention should be implemented in practice, was not supported or was refuted by the evidence, or should be used only in research (inconclusive evidence).

Results

We selected 37 reviews; most concerned the prevention of caries. The methodological quality was high, except for the assessment of reporting bias. In 7 reviews (19%), the research showed that benefits outweighed harms; in 1, the experimental intervention was found ineffective; and in 29 (78%), evidence was insufficient to assess benefits and harms. In the 7 reviews, topical fluoride treatments (with toothpaste, gel or varnish) were found effective for permanent and deciduous teeth in children and adolescents, and sealants for occlusal tooth surfaces of permanent molars.

Conclusions

Cochrane reviews of paediatric dentistry were of high quality. They provided strong evidence that topical fluoride treatments and sealants are effective for children and adolescents and thus should be implemented in practice. However, a substantial number of reviews yielded inconclusive evidence.

Keywords

Systematic reviews Cochrane collaboration Children oral health Implication for practice Caries prevention

Background

Evidence-based dentistry has contributed substantially to improving the quality of oral health in general and in the paediatric population in particular. Systematic reviews of randomized controlled trials (RCTs) are considered the highest standard in evidence-based healthcare available to clinicians to guide clinical practice. The Cochrane Collaboration is the world’s largest producer of systematic reviews of primary research in human health care and health policy [1]. The Cochrane Oral Health Group (COHG) is one of 50 review groups within the Cochrane Collaboration.

High methodological quality is necessary for valid interpretation and application of systematic review findings [2, 3]. Moreover, systematic reviews can be a source of knowledge for healthcare practice, provided that they give conclusive evidence that interventions are effective, ineffective or harmful. To our knowledge, no study has assessed the methodological quality and implications for practice of Cochrane systematic reviews of paediatric oral health.

We aimed to identify all existing systematic reviews of the COHG related to paediatric dentistry and oral health and to summarize the most relevant characteristics of the reviews. Our second objective was to evaluate the methodological quality of the systematic reviews using A Measurement Tool to Assess Systematic Reviews (AMSTAR), a validated 11-item quality assessment tool. Finally, we aimed to assess the implications for practice in the review conclusions and provide an overview of clinical implications about the usefulness of paediatric oral health interventions in practice.

Methods

We conducted a methodological survey including all paediatric reviews indexed in the Dentistry and Oral Health category of the COHG reviews. We extracted data on characteristics of included Cochrane reviews, then assessed the methodological quality using the AMSTAR checklist. Finally, we examined the review conclusions to assess whether the experimental intervention was conclusive, ineffective, harmful or contained inconclusive evidence.

Criteria for considering systematic reviews

Eligible systematic reviews were of paediatric dentistry and oral health produced by the COHG. In the first step, we selected systematic reviews if the authors clearly reported participants as “children” or “adolescents” in the title and objectives. If this was not clear, we systematically examined the full text of selected articles to determine whether authors defined an upper age limit as selection criteria or whether the maximum age of included patients was ≤ 18 years old. We selected updates of systematic reviews rather than initial versions. We excluded systematic reviews that included at least one RCT of adults and reviews that did not mention the age of participants.

Search methods for systematic reviews

We identified eligible Cochrane systematic reviews indexed in the Dentistry and Oral Health category of the COHG at http://www.thecochranelibrary.com. The last search was conducted in November 2013. Two authors independently and in duplicate screened all full-text reports. Any disagreements were resolved by discussion.

Data extraction

Characteristics of included Cochrane systematic reviews

Two reviewers extracted data independently and in duplicate, with discrepancies resolved by discussion. For each systematic review, we recorded the publication year, the country, the topic, the participants and the primary outcomes. For each meta-analysis of primary outcomes, we recorded the experimental intervention, the comparator, the number of RCTs examined, the number of participants, and the relative effect (treatment effect measure and combined estimate [95% confidence interval]).

Assessment of methodological quality of Cochrane systematic reviews

Two reviewers independently and in duplicate evaluated the methodological quality of systematic reviews using the AMSTAR checklist, a measurement tool of 11 items [4, 5]. Disagreements were resolved with a third author. We did not use the PRISMA checklist because it is not intended to be a quality assessment tool as compared with the AMSTAR, which is a reliable and valid measurement tool to assess the methodological quality of systematic reviews [5, 6]. The following characteristics were assessed: a priori design, study selection and data extraction, literature search, status of publication, characteristics of the included and excluded studies, scientific quality of the included studies, methods used to combine the findings of studies, publication bias and conflict of interest.

Assessment of the implications for practice in conclusions sections of Cochrane systematic reviews

Two reviewers independently examined the implications-for-practice paragraph in the conclusions sections of all selected systematic reviews. Disagreements were resolved by a third author. For each review, we assessed whether the experimental intervention should be implemented in practice (ie, conclusive evidence that the intervention was effective and not harmful), was ineffective and should not be used in practice, was harmful and should not be used in practice, or should be used only in research (ie, the evidence identified was inconclusive; that is, the intervention could be beneficial or harmful) [7, 8]. The experimental intervention was considered ineffective if the evidence showed that it was ineffective for all primary outcomes, harmful if the evidence showed it was harmful for at least one adverse event, to be used in research only if the evidence was inconclusive for at least one primary outcome, or should be implemented in practice if the evidence showed that it was effective for all primary outcomes and not harmful, with no adverse events.

Results

Eligible Cochrane systematic reviews

The search yielded 278 Cochrane systematic reviews that specifically addressed dentistry and oral health issues. After 7 duplicates were removed, we finally included 37 systematic reviews focused on paediatric oral health [945].

Characteristics of included Cochrane systematic reviews

The median year of publication was 2008 (range 2002–2013) (Table 1). Most systematic reviews (57%) were performed in the United Kingdom. The reviews mainly concerned interventions for the prevention of dental caries (n = 16), orthodontic treatment and oral surgery (n = 4 for each domain), treatment of dental caries (n = 3) and behavior management (n = 2). Details are given in Additional file 1: Table S1.
Table 1

Characteristics of included systematic reviews

Characteristics

No of reviews (%)

n = 37

Publication year

 

  2002 – 2004

9 (24%)

  2005 – 2007

8 (22%)

  2008 – 2010

8 (22%)

  2011 – 2013

12 (32%)

Country

 

  United Kingdom

21 (57%)

  Brazil

3 (8%)

  Germany

2 (5%)

  China

2 (5%)

  Ireland

2 (5%)

  Finland

2 (5%)

  Oman

1 (3%)

  Syrian Arab Republic

1 (3%)

  South Africa

1 (3%)

  France

1 (3%)

  The Netherlands

1 (3%)

Topic

 

  Prevention of dental caries

16 (43%)

  Orthodontic treatment

4 (10%)

  Oral surgery

4 (10%)

  Treatment of dental caries

3 (8%)

  Behavior management

2 (5%)

  Treatment of oral pain

1 (3%)

  Dental fluorosis

1 (3%)

  Treatment of dental development disorder

1 (3%)

  Treatment of gingivostomatitis

1 (3%)

  Anesthesia

1 (3%)

  Treatment of dental trauma

1 (3%)

  Orthopedic treatment

1 (3%)

  Craniofacial anomaly

1 (3%)

Comparisons of primary outcomes

In 30 reviews, no meta-analysis was performed for primary outcomes in 65 comparisons: for 9 comparisons, no RCT existed for the primary outcomes; for 53 comparisons, only 1 RCT existed for the primary outcomes; and for 3 comparisons (2, 3, and 3 RCTs), no meta-analysis was performed for the primary outcomes. In 15 reviews, 65 meta-analyses were performed for primary outcomes (at least 2 RCTs included). Among the 65 meta-analyses, the median number of RCTs per meta-analysis was 3 [Q1–Q3 2–6, min–max 2–133] and the median number of patients per meta-analysis was 360 [Q1–Q3 182–1,673, min–max 50–65,179]. The number of meta-analyses with continuous outcomes was 61 (94%). Details are given in Additional file 2: Table S2.

Methodological quality of Cochrane systematic reviews

The overall quality of the selected reviews was high according to the AMSTAR checklist. In all reviews, the reporting of 8 of the 11 items was adequate (Figure 1). The weakest area was failure to report the likelihood of publication bias, in 14 reviews (38%), which did not assess publication bias [1113, 17, 19, 20, 2426, 34, 35, 38, 42, 43]. One review did not use “grey” literature as an inclusion criterion [34] and in another, the methods used to combine the findings of studies were inappropriate [38].
https://static-content.springer.com/image/art%3A10.1186%2F1472-6831-14-35/MediaObjects/12903_2013_Article_359_Fig1_HTML.jpg
Figure 1

Assessment of methodological quality of included studies using AMSTAR.

Implications for practice in Cochrane systematic reviews

For the 37 systematic reviews, 7 (19%) concluded that specific interventions should be implemented in practice (ie, interventions for which research showed that benefits outweighed harms), and 1 concluded that specific interventions should not be used in practice because of ineffectiveness (Table 2). All experimental interventions that had been shown to be effective involved prevention of dental caries. Research evidence supported the effectiveness of topical fluoride treatments (with toothpaste, gel or varnish) for permanent and deciduous teeth in children and adolescents, and sealants for occlusal tooth surfaces of permanent molars. We did not identify any intervention for which research showed that harms outweighed benefits. However, for 29 reviews (78%), the evidence was inconclusive because it was limited (see Additional file 3: Table S3).
Table 2

Characteristics of systematic reviews with experimental interventions that had been found effective and should be implemented in practice

Review

Participants

Intervention

Comparator

Outcome

# RCTs

# pts

Relative effect [95% CI]

1830

Permanent teeth in children and adolescents

Resin-based sealant applications on occlusal tooth surfaces of permanent molars

No sealant application

Dentine caries in permanent molars Follow-up: 2 yr

6

1,066

OR 0.12 [0.07;0.19]

2278

Permanent teeth in children and adolescents

Fluoride toothpaste

Placebo

D(M)FS increment - nearest to 3 yr

70

42,300

SMD -0.31 [-0.35;-0.27]

2278

Permanent teeth in children and adolescents

Fluoride toothpaste

Placebo

D(M)FT increment- nearest to 3 yr

53

32,371

SMD -0.28 [-0.33;-0.23]

2279

Permanent and deciduous teeth in children and adolescents

Fluoride varnishes

Placebo/no treatment

D(M)FS increment - nearest to 3 yr

7

2,278

SMD -0.46 [-0.65;-0.26]

2280

Permanent and deciduous teeth in children and adolescents

Fluoride gels

Placebo

D(M)FS increment - nearest to 3 yr

14

4,492

SMD -0.20 [-0.29;-0.10]

2280

Permanent and deciduous teeth in children and adolescents

Fluoride gels

No treatment

D(M)FS increment - nearest to 3 yr

9

2,677

SMD -0.46 [-0.65;-0.27]

2280

Permanent and deciduous teeth in children and adolescents

Fluoride gels

Placebo

D(M)FT increment - nearest to 3 years

4

1,525

SMD -0.19 [-0.29;-0.09]

2280

Permanent and deciduous teeth in children and adolescents

Fluoride gels

No treatment

D(M)FT increment - nearest to 3 years

6

1,673

SMD -0.73 [-1.13;-0.32]

2284

Permanent and deciduous teeth in children and adolescents

Fluoride mouthrinses

Placebo/no treatment

D(M)FS increment - nearest to 3 years

34

14,663

SMD -0.30 [-0.36;-0.24]

2284

Permanent and deciduous teeth in children and adolescents

Fluoride mouthrinses

Placebo/no treatment

D(M)FT increment - nearest to 3 years

13

5,105

SMD -0.28 [-0.37;-0.20]

2782

Permanent and deciduous teeth in children and adolescents

Topical fluoride

Placebo/no treatment

D(M)FS increment - nearest to 3 years

133

65,179

PF 0.26 [0.23;0.29]

2782

Permanent and deciduous teeth in children and adolescents

Topical fluoride

Placebo/no treatment

D(M)FT increment - nearest to 3 yr

79

41,391

PF 0.26 [0.21;0.30]

2782

Permanent and deciduous teeth in children and adolescents

Topical fluoride

Placebo/no treatment

d(e)fs increment - nearest to 3 yr

5

1,685

PF 0.33 [0.22;0.44]

7868

General population of children and adolescents

Fluoride toothpaste

Placebo or other fluoride toothpaste

D(M)FS increment - nearest to 3 yr

74

Not clear

PF 19.79 [16.72;22.87]

7868

General population of children and adolescents

Fluoride toothpaste

Placebo or other fluoride toothpaste

D(M)FT increment - nearest to 3 yr

54

Not clear

PF 21.1 [16.86;25.47]

7868

General population of children and adolescents

Fluoride toothpaste

Placebo or other fluoride toothpaste

D(M)FS increment nearest to 3 yr

74

Not clear

SMD -0.24 [-0.27;-0.20]

7868

General population of children and adolescents

Fluoride toothpaste

Placebo or other fluoride toothpaste

D(M)FT increment - nearest to 3 yr

54

Not clear

SMD -0.24 [-0.28;-0.20]

7868

General population of children and adolescents

Fluoride toothpaste

Placebo or other fluoride toothpaste

d(m)fs increment - nearest to 3 yr

3

Not clear

PF 34.82 [25.68-43.96]

7868

General population of children and adolescents

Fluoride toothpaste

Placebo or other fluoride toothpaste

d(m)ft increment - nearest to 3 yr

3

Not clear

PF 12.18 [5.08-19.29]

7868

General population of children and adolescents

Fluoride toothpaste

Placebo or other fluoride toothpaste

Proportion developing new caries (permanent)

8

Not clear

RR 0.98 [0.94-1.02]

7868

General population of children and adolescents

Fluoride toothpaste

Placebo or other fluoride toothpaste

Proportion developing new caries (deciduous)

3

Not clear

RR 0.87 [0.81-0.93]

Yr, year; #, number; pts, participants; 95% CI, 95% confidence interval; RR: relative risk; OR: odds ratio; SMD: standardized mean difference; PF: prevented fraction = mean caries increment in controls – mean caries increment in the treated group/mean caries increment in controls. D(M)FS increment: caries increment on permanent tooth surfaces; D(M)FT increment: caries increment in permanent teeth; dmfs increment: caries increment on deciduous tooth surfaces; dmft increment: caries increment in deciduous teeth.

Discussion

Our study shows that the number of Cochrane systematic reviews in paediatric dentistry and oral health has increased during the last few years. This situation should improve the basis for clinical decision-making because systematic reviews are considered essential sources of evidence for guideline development [46]. The methodological quality of most of our reviews was high, corresponding to the high quality standards of the Cochrane Collaboration. Nevertheless, the likelihood of publication bias was not frequently assessed. This is an important factor to take into account in the conduct of a meta-analysis and in the interpretation of results [47].

Cochrane reviews should not define recommendations for practice because this requires assumptions about the relative importance of benefits and harms of an intervention and judgements that are beyond the scope of a systematic review. However, Cochrane review authors always propose implications for practice. Our study demonstrated that most of the reviews (43%) and all interventions supported by research evidence focused on the prevention of dental caries. For children and adolescents, topical fluoride treatments (with toothpaste, gel or varnish) were found effective for permanent and deciduous teeth and sealants for occlusal tooth surfaces of permanent molars. The predominance of this topic seems justified because it is the most important from a public health policy viewpoint. Early childhood caries is the most frequent chronic disease affecting young children and is 5 times more common than asthma [48]. The selected reviews also concerned orthodontic treatment and oral surgery. However, for clinicians, several secondary research gaps are the management of oro-dental trauma or conservative treatments. Actually, the latter involve materials that may be harmful because of some toxicity [49, 50].

Many of our reviews (78%) produced inconclusive evidence. The most common reasons for failure to provide reliable information to guide clinical decisions are the small numbers of RCTs and patients per meta-analysis. According to a cross-sectional descriptive analysis about characteristics of meta-analyses in the Cochrane Database of Systematic Reviews, the median number of RCTs included in meta-analyses was 3 (Q1–Q3 2–6) and the median number of patients was 91 (Q1–Q3 44–210) [51]. Our findings are consistent with these figures and emphasize that more high-quality primary research may be frequently needed to reach conclusiveness. However, none of the selected reviews was empty; that is, randomized evidence always existed and was included in the review, even when inconclusive. Another explanation for the inconclusiveness may be the inability to perform data synthesis. Diversity in outcomes measured across RCTs within a review may substantially limit the ability to perform meta-analyses and may explain the lack of recommendations [52, 53]. Many meta-analyses frequently exclude a large number of RCTs because outcomes are too different between studies [54]. The standardization of outcomes was initiated by the OMERACT group [55] and is expanding with the COMET Initiative [56]. In the field of dentistry, some studies have defined core outcome sets to help solve this problem, such as in implantology [5760] and for the evaluation of pulp treatments in primary teeth [61]. Finally, all systematic reviews should be considered as informative because they may allow for identifying well-informed uncertainties about the effects of treatments [62, 63].

Previous methodological surveys assessed the conduct quality of systematic reviews in the field of dentistry [6466]. In a study of 109 systematic reviews published in major orthodontic journals, 26 were published in the Cochrane Database of Systematic Reviews. In all, 21% of the selected reviews satisfied 9 or more of the 11 AMSTAR criteria [64, 65]. However, to our best knowledge, no methodological survey concerned specifically pediatric oral health.

Our study has some limitations. Indeed, we considered only Cochrane systematic reviews in our study, but many non-Cochrane systematic reviews have also assessed interventions in the paediatric oral health field [67]. Nevertheless, Cochrane systematic reviews are the highest standard in evidence-based health care. Moreover, Cochrane reviews have a standard structure, which always includes implications for practice. Another potential limitation is that we assessed whether the experimental intervention should be used in practice, should not be used in practice or should be used only in research based on the Implications-for-practice section only and we did not critically judge the review evidence ourselves. However, Cochrane review authors describe clinical implications only after describing the quality of evidence and the balance of benefits and harms.

Conclusions

The Cochrane reviews of paediatric dentistry and oral health were of high quality. They provided strong evidence that topical fluoride treatments and sealants are effective for children and adolescents and thus should be implemented in practice. However, a substantial number of reviews yielded inconclusive findings.

Declarations

Acknowledgments

We thank Laura Smales (BioMedEditing, Toronto, Canada) for editing the manuscript.

Authors’ Affiliations

(1)
Institut National de la Santé et de la Recherche Médicale
(2)
Assistance Publique-Hôpitaux de Paris, Hôpital Bretonneau, Service d’Odontologie
(3)
Université Paris Descartes - Sorbonne Paris Cité, Faculté de Chirurgie Dentaire, Unité de Recherches Biomatériaux Innovants et Interface EA4462
(4)
Assistance Publique-Hôpitaux de Paris, Hôpital Charles Foix, Service d’Odontologie

References

  1. Higgins J, Green S: Cochrane Handbook for Systematic Reviews of Interventions 5.1.0 [updated March 2011]. 2011, The Cochrane Collaboration, Available from: http://www.cochrane-handbook.org Google Scholar
  2. Moher D, Jadad AR, Nichol G, Penman M, Tugwell P, Walsh S: Assessing the quality of randomized controlled trials: an annotated bibliography of scales and checklists. Control Clin Trials. 1995, 16 (1): 62-73. 10.1016/0197-2456(94)00031-W.View ArticlePubMedGoogle Scholar
  3. Mulrow CD: Rationale for systematic reviews. BMJ. 1994, 309 (6954): 597-599. 10.1136/bmj.309.6954.597.View ArticlePubMedPubMed CentralGoogle Scholar
  4. Shea BJ, Grimshaw JM, Wells GA, Boers M, Andersson N, Hamel C, Porter AC, Tugwell P, Moher D, Bouter LM: Development of AMSTAR: a measurement tool to assess the methodological quality of systematic reviews. BMC Med Res Methodol. 2007, 7: 10-10.1186/1471-2288-7-10.View ArticlePubMedPubMed CentralGoogle Scholar
  5. Shea BJ, Hamel C, Wells GA, Bouter LM, Kristjansson E, Grimshaw J, Henry DA, Boers M: AMSTAR is a reliable and valid measurement tool to assess the methodological quality of systematic reviews. J Clin Epidemiol. 2009, 62 (10): 1013-1020. 10.1016/j.jclinepi.2008.10.009.View ArticlePubMedGoogle Scholar
  6. Liberati A, Altman DG, Tetzlaff J, Mulrow C, Gotzsche PC, Ioannidis JP, Clarke M, Devereaux PJ, Kleijnen J, Moher D: The PRISMA statement for reporting systematic reviews and meta-analyses of studies that evaluate health care interventions: explanation and elaboration. PLoS Med. 2009, 6 (7): e1000100-10.1371/journal.pmed.1000100.View ArticlePubMedPubMed CentralGoogle Scholar
  7. Garner S, Docherty M, Somner J, Sharma T, Choudhury M, Clarke M, Littlejohns P: Reducing ineffective practice: challenges in identifying low-value health care using Cochrane systematic reviews. J Health Serv Res Policy. 2013, 18 (1): 6-12. 10.1258/jhsrp.2012.012044.View ArticlePubMedGoogle Scholar
  8. Clarke M, Clarke T, Clarke L: Cochrane systematic reviews as a source of information for practice and trials. Trials. 2011, 12 (Suppl 1): A49-10.1186/1745-6215-12-S1-A49.View ArticlePubMed CentralGoogle Scholar
  9. Ahovuo-Saloranta A, Forss H, Walsh T, Hiiri A, Nordblad A, Makela M, Worthington HV: Sealants for preventing dental decay in the permanent teeth. Cochrane Database Syst Rev. 2013, , 3, CD001830Google Scholar
  10. Al-Harasi S, Ashley PF, Moles DR, Parekh S, Walters V: Hypnosis for children undergoing dental treatment. Cochrane Database Syst Rev. 2010, , 8, CD007154Google Scholar
  11. Ashley PF, Parekh S, Moles DR, Anand P, Behbehani A: Preoperative analgesics for additional pain relief in children and adolescents having dental treatment. Cochrane Database Syst Rev. 2012, , 9, CD008392Google Scholar
  12. Ashley PF, Williams CE, Moles DR, Parry J: Sedation versus general anaesthesia for provision of dental treatment in under 18 year olds. Cochrane Database Syst Rev. 2012, , 11, CD006334Google Scholar
  13. Beirne P, Clarkson JE, Worthington HV: Recall intervals for oral health in primary care patients. Cochrane Database Syst Rev. 2007, , 4, CD004346Google Scholar
  14. Belmonte FM, Macedo CR, Day PF, Saconato H, Fernandes Moca Trevisani V: Interventions for treating traumatised permanent front teeth: luxated (dislodged) teeth. Cochrane Database Syst Rev. 2013, , 4, CD006203Google Scholar
  15. Benson PE, Parkin N, Millett DT, Dyer FE, Vine S, Shah A: Fluorides for the prevention of white spots on teeth during fixed brace treatment. Cochrane Database Syst Rev. 2004, , 3, CD003809Google Scholar
  16. Bessell A, Hooper L, Shaw WC, Reilly S, Reid J, Glenny AM: Feeding interventions for growth and development in infants with cleft lip, cleft palate or cleft lip and palate. Cochrane Database Syst Rev. 2011, , 2, CD003315Google Scholar
  17. Bonner BC, Clarkson JE, Dobbyn L, Khanna S: Slow-release fluoride devices for the control of dental decay. Cochrane Database Syst Rev. 2006, , 4, CD005101Google Scholar
  18. Carvalho FR, Lentini-Oliveira D, Machado MA, Prado GF, Prado LB, Saconato H: Oral appliances and functional orthopaedic appliances for obstructive sleep apnoea in children. Cochrane Database Syst Rev. 2007, , 2, CD005520Google Scholar
  19. Cooper AM, O’Malley LA, Elison SN, Armstrong R, Burnside G, Adair P, Dugdill L, Pine C: Primary school-based behavioural interventions for preventing caries. Cochrane Database Syst Rev. 2013, , 5, CD009378Google Scholar
  20. Dashash M, Yeung CA, Jamous I, Blinkhorn A: Interventions for the restorative care of amelogenesis imperfecta in children and adolescents. Cochrane Database Syst Rev. 2013, , 6, CD007157Google Scholar
  21. Guo J, Li C, Zhang Q, Wu G, Deacon SA, Chen J, Hu H, Zou S, Ye Q: Secondary bone grafting for alveolar cleft in children with cleft lip or cleft lip and palate. Cochrane Database Syst Rev. 2011, , 6, CD008050Google Scholar
  22. Harrison JE, O’Brien KD, Worthington HV: Orthodontic treatment for prominent upper front teeth in children. Cochrane Database Syst Rev. 2007, , 3, CD003452Google Scholar
  23. Hiiri A, Ahovuo-Saloranta A, Nordblad A, Makela M: Pit and fissure sealants versus fluoride varnishes for preventing dental decay in children and adolescents. Cochrane Database Syst Rev. 2010, , 3, CD003067Google Scholar
  24. Innes NP, Ricketts DN, Evans DJ: Preformed metal crowns for decayed primary molar teeth. Cochrane Database Syst Rev. 2007, , 1, CD005512Google Scholar
  25. Lentini-Oliveira D, Carvalho FR, Qingsong Y, Junjie L, Saconato H, Machado MA, Prado LB, Prado GF: Orthodontic and orthopaedic treatment for anterior open bite in children. Cochrane Database Syst Rev. 2007, , 2, CD005515Google Scholar
  26. Lourenco-Matharu L, Ashley PF, Furness S: Sedation of children undergoing dental treatment. Cochrane Database Syst Rev. 2012, , 3, CD003877Google Scholar
  27. Marinho VC, Higgins JP, Logan S, Sheiham A: Fluoride gels for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2002, , 2, CD002280Google Scholar
  28. Marinho VC, Higgins JP, Logan S, Sheiham A: Topical fluoride (toothpastes, mouthrinses, gels or varnishes) for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2003, , 4, CD002782Google Scholar
  29. Marinho VC, Higgins JP, Logan S, Sheiham A: Fluoride mouthrinses for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2003, , 3, CD002284Google Scholar
  30. Marinho VC, Higgins JP, Sheiham A, Logan S: Fluoride toothpastes for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2003, , 1, CD002278Google Scholar
  31. Marinho VC, Higgins JP, Sheiham A, Logan S: Combinations of topical fluoride (toothpastes, mouthrinses, gels, varnishes) versus single topical fluoride for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2004, , 1, CD002781Google Scholar
  32. Marinho VC, Higgins JP, Sheiham A, Logan S: One topical fluoride (toothpastes, or mouthrinses, or gels, or varnishes) versus another for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2004, , 1, CD002780Google Scholar
  33. Marinho VC, Worthington HV, Walsh T, Clarkson JE: Fluoride varnishes for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2013, , 7, CD002279Google Scholar
  34. Mettes TD, Ghaeminia H, Nienhuijs ME, Perry J, van der Sanden WJ, Plasschaert A: Surgical removal versus retention for the management of asymptomatic impacted wisdom teeth. Cochrane Database Syst Rev. 2012, , 6, CD003879Google Scholar
  35. Millett DT, Cunningham SJ, O’Brien KD, Benson P, Williams A, de Oliveira CM: Orthodontic treatment for deep bite and retroclined upper front teeth in children. Cochrane Database Syst Rev. 2006, , 4, CD005972Google Scholar
  36. Nadin G, Goel BR, Yeung CA, Glenny AM: Pulp treatment for extensive decay in primary teeth. Cochrane Database Syst Rev. 2003, , 1, CD003220Google Scholar
  37. Nasser M, Fedorowicz Z, Khoshnevisan MH, Shahiri Tabarestani M: Acyclovir for treating primary herpetic gingivostomatitis. Cochrane Database Syst Rev. 2008, , 4, CD006700Google Scholar
  38. Nasser M, Fedorowicz Z, Newton JT, Nouri M: Interventions for the management of submucous cleft palate. Cochrane Database Syst Rev. 2008, , 1, CD006703Google Scholar
  39. Parkin N, Benson PE, Thind B, Shah A: Open versus closed surgical exposure of canine teeth that are displaced in the roof of the mouth. Cochrane Database Syst Rev. 2008, , 4, CD006966Google Scholar
  40. Parkin N, Furness S, Shah A, Thind B, Marshman Z, Glenroy G, Dyer F, Benson PE: Extraction of primary (baby) teeth for unerupted palatally displaced permanent canine teeth in children. Cochrane Database Syst Rev. 2012, , 12, CD004621Google Scholar
  41. Tubert-Jeannin S, Auclair C, Amsallem E, Tramini P, Gerbaud L, Ruffieux C, Schulte AG, Koch MJ, Rege-Walther M, Ismail A: Fluoride supplements (tablets, drops, lozenges or chewing gums) for preventing dental caries in children. Cochrane Database Syst Rev. 2011, , 12, CD007592Google Scholar
  42. Walsh T, Worthington HV, Glenny AM, Appelbe P, Marinho VC, Shi X: Fluoride toothpastes of different concentrations for preventing dental caries in children and adolescents. Cochrane Database Syst Rev. 2010, , 1, CD007868Google Scholar
  43. Wong MC, Glenny AM, Tsang BW, Lo EC, Worthington HV, Marinho VC: Topical fluoride as a cause of dental fluorosis in children. Cochrane Database Syst Rev. 2010, , 1, CD007693Google Scholar
  44. Yengopal V, Harneker SY, Patel N, Siegfried N: Dental fillings for the treatment of caries in the primary dentition. Cochrane Database Syst Rev. 2009, , 2, CD004483Google Scholar
  45. Yeung CA, Hitchings JL, Macfarlane TV, Threlfall AG, Tickle M, Glenny AM: Fluoridated milk for preventing dental caries. Cochrane Database Syst Rev. 2005, , 3, CD003876Google Scholar
  46. Atkins D, Best D, Briss PA, Eccles M, Falck-Ytter Y, Flottorp S, Guyatt GH, Harbour RT, Haugh MC, Henry D, Hill S, Jaeschke R, Leng G, Liberati A, Magrini N, Mason J, Middleton P, Mrukowicz J, O’Connell D, Oxman AD, Phillips B, Schünemann HJ, Edejer T, Varonen H, Vist GE, Williams JW, Zaza S, GRADE Working Group: Grading quality of evidence and strength of recommendations. BMJ. 2004, 328 (7454): 1490-View ArticlePubMedGoogle Scholar
  47. Egger M, Davey Smith G, Schneider M, Minder C: Bias in meta-analysis detected by a simple, graphical test. BMJ. 1997, 315 (7109): 629-634. 10.1136/bmj.315.7109.629.View ArticlePubMedPubMed CentralGoogle Scholar
  48. Oral health in America: a report of the Surgeon General. J Calif Dent Assoc. 2000, 28 (9): 685-695.
  49. Goldberg M: In vitro and in vivo studies on the toxicity of dental resin components: a review. Clin Oral Investig. 2008, 12 (1): 1-8. 10.1007/s00784-007-0162-8.View ArticlePubMedGoogle Scholar
  50. Koral SM: Mercury from dental amalgam: exposure and risk assessment. Compend Contin Educ Dent. 2013, 34 (2): 138-140. 142, 144 passimPubMedGoogle Scholar
  51. Davey J, Turner RM, Clarke MJ, Higgins JP: Characteristics of meta-analyses and their component studies in the Cochrane Database of Systematic Reviews: a cross-sectional, descriptive analysis. BMC Med Res Methodol. 2011, 11: 160-10.1186/1471-2288-11-160.View ArticlePubMedPubMed CentralGoogle Scholar
  52. Clarke M: Standardising outcomes for clinical trials and systematic reviews. Trials. 2007, 8: 39-10.1186/1745-6215-8-39.View ArticlePubMedPubMed CentralGoogle Scholar
  53. Williamson P, Clarke M: The COMET (Core Outcome Measures in Effectiveness Trials) initiative: its role in improving cochrane reviews. Cochrane Database Syst Rev. 2012, , 5, ED000041Google Scholar
  54. Furukawa TA, Watanabe N, Omori IM, Montori VM, Guyatt GH: Association between unreported outcomes and effect size estimates in Cochrane meta-analyses. JAMA. 2007, 297 (5): 468-470.View ArticlePubMedGoogle Scholar
  55. Tugwell P, Boers M, Brooks P, Simon L, Strand V, Idzerda L: OMERACT: an international initiative to improve outcome measurement in rheumatology. Trials. 2007, 8: 38-10.1186/1745-6215-8-38.View ArticlePubMedPubMed CentralGoogle Scholar
  56. Williamson P, Altman D, Blazeby J, Clarke M, Gargon E: Driving up the quality and relevance of research through the use of agreed core outcomes. J Health Serv Res Policy. 2012, 17 (1): 1-2. 10.1258/jhsrp.2011.011131.View ArticlePubMedGoogle Scholar
  57. Carr A, Wolfaardt J, Garrett N: Capturing patient benefits of treatment. Int J Oral Maxillofac Implants. 2011, 26 (Suppl): 85-92. discussion 101-102PubMedGoogle Scholar
  58. Faggion CM, Listl S, Tu YK: Assessment of endpoints in studies on peri-implantitis treatment–a systematic review. J Dent. 2010, 38 (6): 443-450. 10.1016/j.jdent.2010.03.003.View ArticlePubMedGoogle Scholar
  59. Needleman I, Chin S, O’Brien T, Petrie A, Donos N: Systematic review of outcome measurements and reference group(s) to evaluate and compare implant success and failure. J Clin Periodontol. 2012, 39 (Suppl 12): 122-132.View ArticlePubMedGoogle Scholar
  60. Papaspyridakos P, Chen CJ, Singh M, Weber HP, Gallucci GO: Success criteria in implant dentistry: a systematic review. J Dent Res. 2012, 91 (3): 242-248. 10.1177/0022034511431252.View ArticlePubMedGoogle Scholar
  61. Smail-Faugeron V, Fron Chabouis H, Durieux P, Attal JP, Muller-Bolla M, Courson F: Development of a core set of outcomes for randomized controlled trials with multiple outcomes–example of pulp treatments of primary teeth for extensive decay in children. PLoS One. 2013, 8 (1): e51908-10.1371/journal.pone.0051908.View ArticlePubMedPubMed CentralGoogle Scholar
  62. Chalmers I: Well informed uncertainties about the effects of treatments. BMJ. 2004, 328 (7438): 475-476. 10.1136/bmj.328.7438.475.View ArticlePubMedPubMed CentralGoogle Scholar
  63. Chalmers I: Systematic reviews and uncertainties about the effects of treatments. Cochrane Database Syst Rev. 2011, , 2011, ED000004Google Scholar
  64. Fleming PS, Seehra J, Polychronopoulou A, Fedorowicz Z, Pandis N: Cochrane and non-Cochrane systematic reviews in leading orthodontic journals: a quality paradigm?. Eur J Orthod. 2013, 35 (2): 244-248. 10.1093/ejo/cjs016.View ArticlePubMedGoogle Scholar
  65. Fleming PS, Seehra J, Polychronopoulou A, Fedorowicz Z, Pandis N: A PRISMA assessment of the reporting quality of systematic reviews in orthodontics. Angle Orthod. 2013, 83 (1): 158-163. 10.2319/032612-251.1.View ArticlePubMedGoogle Scholar
  66. Sequeira-Byron P, Fedorowicz Z, Jagannath VA, Sharif MO: An AMSTAR assessment of the methodological quality of systematic reviews of oral healthcare interventions published in the Journal of Applied Oral Science (JAOS). J Appl Oral Sci. 2011, 19 (5): 440-447. 10.1590/S1678-77572011000500002.View ArticlePubMedPubMed CentralGoogle Scholar
  67. ADA. Center for Evidence-Based Dentistry. Available: http://www.cdc.gov/nchs/nhanes.htm
  68. Pre-publication history

    1. The pre-publication history for this paper can be accessed here:http://www.biomedcentral.com/1472-6831/14/35/prepub

Copyright

© Smaïl-Faugeron et al.; licensee BioMed Central Ltd. 2014

This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.