Direct restorative materials for treating cavitated carious lesions


Dental caries is the most common non communicable disease affecting billions of people worldwide although it is almost completely preventable. While early carious lesions may be managed using non- restorative management option cavitated lesions usually require restoration of form function and aesthetics to protect the pulp preserve tooth, preserve tooth structure and prevent caries progression.  Direct restorative material include amalgam, conventional glass ionomer cement (GIC), compomers, preformed aesthetic crowns (primary teeth only), preformed metal crowns, resin- modified GIC (RMGIC), and resin composite (macrofilled, hybrid, or nanocomposite).

The aim of this review was to determine the effect of different direct restorative materials for treating cavitated caries lesions on anterior and posterior primary and permanent teeth.


A protocol was registered on the PROSPERO database. Searches were conducted in Medline (Ovid), Embase, the Cochrane Central Register of Controlled Trials (CENTRAL), and the World Health Organisation International Clinical Trials Registry Platform databases.  Parallel or split mouth randomised controlled trials (RCTs) comparing the effectiveness of direct restorative materials placed in vital, non-endodontically treated primary and permanent teeth and commercially available in the United States were considered. Pairs of reviewers independently screened and selected studies with two reviewers independently extracting data with disputes settled by consensus.  A broad range of clinically oriented and patient-important outcomes were considered. For dichotomous outcomes risk differences (RDs) were calculated and mean differences (MDs) for continuous outcomes. For anatomic form and marginal adaptation, we used the thresholds of clinical acceptability defined by the primary study authors were used or thresholds for acceptable and unacceptable scores outcomes as defined for the US Public Health Service and modified US Public Health Service criteria. A planned network meta-analysis (NMA) was not conducted because of spare networks so pair-wise meta-analyses were conducted.  Risk of bias for included RCTs was assessed by 4 reviews independently using the Cochrane Risk of Bias 2 tool.   Certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.


  • 38 trials (12 parallel, 26 split mouth) reported in 42 papers were included.
  • The trials were published between 1994 and 2021 and conducted in 19 countries.
  • 13 RCTs involved the primary dentition reporting data on Class I, II and a combination of Class I and II.
  • 25 Studies involved the permanent dentition reporting data on Class I, II and a combination of Class I and II, Class III, Class IV and root surface restorations.
  • None of the trials were considered to be at low risk of bias, 15 were considered to be at high risk of bias with 23 having some concerns.
  • Quantitative analyses were not possible for many comparisons as there were zero events in both treatment arms of the study.
  • Some trends of comparative effectiveness of materials among moderate and low certainty results were seen: –
  • For Primary teeth
    • Low certainty evidence that the comparative effectiveness of conventional GIC may vary across outcomes when compared with both macrofilled resin composite and compomer for Class I restorations.
    • Moderate to low certainty evidence that conventional GIC may be less effective than RMGIC, macrofilled resin composite, nanocomposite, and hybrid resin composite across most outcomes for Class II restorations.
    • Moderate certainty evidence that preformed metal crowns placed using the Hall technique (HT) are likely more effective than conventional GIC placed using ART on Class II restorations on primary teeth.
  • For Permanent teeth low certainty evidence that: –
    • The comparative effectiveness of conventional GIC may vary across outcomes compared with RMGIC, compomer, and hybrid resin composite for and the effectiveness of nanocomposite and hybrid resin composite may vary across outcomes when compared against each other.
    • Hybrid resin composite may be less effective than both amalgam and macrofilled resin composite, and RMGIC may be more effective than conventional GIC for Class I and II restorations combined.
    • RMGIC may be more effective than hybrid resin composite across all outcomes in Class V restorations.
    • RMGIC may be less effective than conventional GIC across all outcomes in root surface restorations.


The authors concluded: –

We found data to suggest that the effectiveness of each included direct restorative material varied across outcomes. There was also limited evidence to support clinically important differences be- tween the direct restorative materials assessed. Larger studies with longer follow-up periods are needed to assess the long-term effectiveness of direct restorative materials with higher certainty. Given the varying effectiveness seen across materials and outcomes, consideration of additional factors, including patients’ values and preferences, acceptability and feasibility of using dental materials, costs, and health equity, may add utility to the clinical decision-making process.


A review protocol was registered on the PROSPERO database and a good methodological approach was followed.  Three major databases and two clinical trials registries were searched.  Screening and selection of studies was conducted independently by pairs of reviewers with data abstraction being undertaken by two reviewers independently. For some studies it was not possible to separate Class I and II restoration outcomes, so these were considered together. Extracting data for the longest follow-up periods was prioritised and only data for restorative materials available in the USA was extracted. The USA availability restriction led to 108 studies being excluded although some of these included materials that were no longer commercially available.  The relatively small number of RCTs available and lack of data resulted in a number of planned analyses not being conducted including a planned network meta-analyses. Most of the studies included in the review were of low quality so there is a need to improve the design and reporting of studies. As many of the studies reported no outcomes events there is also a need for future studies to be adequately powered and have follow up periods of more than 3 years in order to assess the long-term effectiveness of direct restorative materials.


Primary Paper 

Pilcher L, Pahlke S, Urquhart O, O’Brien KK, Dhar V, Fontana M, González-Cabezas C, Keels MA, Mascarenhas AK, Nascimento MM, Platt JA, Sabino GJ, Slayton RL, Tinanoff N, Young DA, Zero DT, Tampi MP, Purnell D, Salazar J, Megremis S, Bienek D, Carrasco-Labra A. Direct materials for restoring caries lesions: Systematic review and meta-analysis-a report of the American Dental Association Council on Scientific Affairs. J Am Dent Assoc. 2023 Feb;154(2):e1-e98. doi: 10.1016/j.adaj.2022.09.012. Epub 2023 Jan 5. Erratum in: J Am Dent Assoc. 2023 Feb 15;: PMID: 36610925.

Review protocol on PROSPERO

Other references

Dental Elf – 21st Jul 2021

Treatments for cavitated or dentine carious lesions

Dental Elf – 7th Dec 2022

Preformed metal crown on primary molars – Conventional or Hall techniques?

Picture Credits

By Jeffrey Dorfman  , CC BY-SA 3.0, Link


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