This umbrella review was conducted following the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) guidelines (39), and was registered in the Open Science Framework (OSF) under the DOI number DOI 10.17605/OSF.IO/3T2GV (https://archive.org/details/osf-registrations-3t2gv-v1), which is publicly accessible. Furthermore, the reporting of this review adhered to the PRIO-harms checklist (Preferred Reporting Items for Overviews of Systematic Reviews) (40). Given the nature of the study, ethical approval was not required.

Studies eligible for inclusion were systematic reviews (with or without meta-analysis) assessing primary research determining the effect of minimal intervention on carious lesions in primary teeth. No restrictions were applied regarding publication date or language. Excluded publication types were narrative reviews, rapid reviews, interventional studies, observational research, preclinical and basic science studies, protocols, abstracts, case reports, commentaries, letters, opinions, and poster presentations.

For clarity, the research question was structured according to the PICOS framework. The population (P) comprised children with carious lesions in primary teeth. The interventions (I) included minimally invasive strategies such as silver diamine fluoride, atraumatic restorative treatment, sealants, resin infiltration, fluoride varnish, the Hall technique, chemical-mechanical caries removal, laser-assisted techniques, and selective caries excavation. The comparators (C) were conventional restorative or operative treatments, non-invasive management, placebo, or no treatment, as defined within the included systematic reviews. The outcomes (O) encompassed caries arrest or progression, restoration survival or failure, pulp exposure or pulpal vitality, need for retreatment, and absence of periapical pathology. The study designs (S) included systematic reviews, with or without meta-analyses, of primary clinical studies assessing these interventions in primary teeth.

An electronic literature search was conducted on September 25, 2025, using four major databases: PubMed, Cochrane Library, Scopus, Web of Science, Embase and SciELO. To identify additional records, gray literature sources were also consulted, including Google Scholar, ProQuest Dissertations and Theses, and OpenGrey. Reference lists of included studies were manually screened to identify any relevant additional publications. All retrieved articles were imported into Zotero® (Center for History and New Media, Virginia, USA), and duplicates were removed. Detailed search strategies for each database are presented in Supplementary Material S1.

The screening and selection process was carried out using Rayyan® online software (Qatar Computing Research Institute, Qatar). Study selection was conducted in two phases. In the first phase, two independent reviewers (L.C. and T.P.) assessed titles and abstracts. In the second phase, the full texts of potentially relevant studies were evaluated independently by the same reviewers. Disagreements at any stage were resolved through discussion with a third reviewer (H.A.).

Data extraction was carried out independently and in duplicate by two reviewers (V.M. and F.C.O.) using a standardized data collection form. Extracted information was cross-checked for consistency, and disagreements were resolved by a third author (H.A). The following variables were recorded: author names, year of publication, type of systematic review, characteristics of included primary studies, number of studies included in qualitative and quantitative analyses, reported outcomes, main conclusions, and whether the reviews reported adherence to PRISMA guidelines, PROSPERO registration or another public platform, use of the GRADE system, and performance of a meta-analysis.

The methodological quality and meta-bias or the risk of bias of the included systematic reviews was assessed independently and in duplicate by two reviewers (F.C.Z. and R.A.), calibrated (Kappa 0.85), using the AMSTAR-2 checklist (A Measurement Tool to Assess Systemic Reviews) (41) and the ROBIS tool (42). The overall confidence level in the studies was rated as high, moderate, low, or critically low, and the risk of bias was rated as high, unclear or low.

For systematic reviews (SRs) that did not include a meta-analysis, the extracted outcomes were reported by determining the effect of minimal intervention on carious lesions in primary teeth. In cases where the SRs provided a meta-analysis, the results were recorded using either odds ratio (OR), risk ratio (RR), mean difference (MD) or weighted mean difference (WMD).

The primary findings from the included systematic reviews were organized and reported according to key outcomes, including ART, chemical-mechanical caries removal, fluoride varnish, Hall technique, laser, resin infiltration, SDF, sealant and selective excavation.

A total of 498 records were identified through the electronic database search. After eliminating duplicates, 277 unique references remained. In the initial screening phase, titles and abstracts were reviewed, resulting in 61 studies deemed suitable for full-text assessment. Of these, 12 studies were excluded, leaving 49 studies for analysis. Details regarding the exclusion criteria applied during the selection process are provided in Supplementary Material S2. The complete workflow for study identification and selection is illustrated in Figure 1.

The included SRs were published between 2006 and 2025. The studies originated from a diverse range of countries, including Italy (23, 28, 38, 43–46), India (47–49), Saudi Arabia (50–54), Pakistan (50), Romania (43), United Kingdom (27, 43, 44, 55–63), United State (16, 52, 56, 58, 64, 65), Singapore (57, 66), Qatar (66), Germany (57–60, 64, 67, 68), Malaysia (55), Chile (27, 55), Brazil (9, 15, 16, 56, 69–73), Denmark (58), China (33, 74–79), France (80), Switzerland (9, 81), Australia (76), Spain (27), Puerto Rico (82), Greece (81), Austria (81), Netherlands (70, 73, 83) and Japan (78).

The evidence base comprised both systematic reviews with meta-analysis and narrative syntheses, and was mainly underpinned by randomized clinical trials. Across reviews, the most frequently evaluated minimal intervention approaches were silver diamine fluoride (SDF), the Hall technique (HT), atraumatic restorative treatment (ART), resin infiltration, sealants, selective caries removal/partial excavation, chemical-mechanical caries removal (e.g., Papacarie/Carisolv), fluoride varnish, and lasers.

In terms of outcomes, the included SRs predominantly reported clinical endpoints relevant to pediatric caries management, such as caries arrest/progression, restoration survival/failure, treatment success rates, and—when available—pulp-related outcomes (e.g., pulp exposure, symptoms, vitality) and complications during follow-up. A subset of reviews also reported patient-centered or procedural outcomes (e.g., discomfort/pain during treatment) and feasibility aspects (e.g., suitability for community or resource-limited settings). Further details regarding the full characteristics and outcomes reported in each SR are provided in Supplementary Material S3.

25 SRs were considered to have high confidence (9, 15, 27, 28, 43–45, 47, 50, 52, 53, 55–64, 66, 67, 70, 81), 2 SRs had moderate confidence (23, 51), 13 SRs they had low confidence (16, 38, 48, 49, 65, 68, 74, 75, 77–80, 82) and 9 SRs had critically low confidence (33, 46, 54, 69, 71–73, 76, 83) (Supplementary Material S4). Furthermore, 24 SRs were found to have a high risk of bias (16, 23, 33, 38, 46, 48, 49, 51, 54, 65, 68, 69, 71–80, 82, 83) and 25 SRs were found to have a low risk of bias (9, 15, 27, 28, 43–45, 47, 50, 52, 53, 55–64, 66, 67, 70, 81) (Supplementary Material S3).

To mitigate the impact of low-confidence reviews on our overall findings, a sensitivity analysis was conducted, excluding studies with low, moderate or critically low confidence, and high risk of bias. The results presented here are based exclusively on high-confidence and low risk of bias reviews, ensuring the reliability of our conclusions.

Overall, the methodological certainty across reviews was mixed: approximately half of the included SRs were rated as high confidence by AMSTAR-2, whereas the remainder showed limitations leading to moderate-to-critically low confidence. ROBIS judgments followed a similar pattern, with roughly half of the SRs judged as low risk of bias and the other half as high risk of bias. These findings indicate that conclusions should be driven primarily by SRs with high overall confidence and low risk of bias, and that results from lower-quality SRs should be interpreted cautiously. Accordingly, our main conclusions emphasize evidence derived from high-confidence/low-risk SRs, while the full AMSTAR-2 item-level judgments and ROBIS assessments for each SR remain available in Supplementary Materials S3 and S4.

A total of 634 primary studies were identified within the SRs. The degree of overlap according to the CCA index is 1.45%, and this value indicates “slight overlap”. Specifically, 62 studies were included twice, 31 appeared three times, 13 were included four times, 5 appeared five times, 6 were included six times, 3 appeared seven times, 3 were included eight times and 1 study were included nine times. Further details on the degree of overlap and characteristics of the primary studies are provided in Supplementary Material S5. This slight overlap reduces the likelihood that our conclusions are driven by redundant inclusion of the same primary studies across multiple SRs, thereby supporting the independence of the evidence mapped in this umbrella review.

The synthesis of the results is presented in Supplementary Material S3.

Ten SRs (9, 23, 27, 48, 57, 70, 71, 73, 76, 83) evaluated the effect of ART in primary teeth. Overall, ART showed either similar or superior effectiveness compared with conventional treatments. Five SRs reported comparable outcomes, whereas six SRs indicated better performance of ART, particularly in single-surface cavities.

Five SRs (9, 27, 57, 70, 71) meta-analyzed the results, where they found that the OR ranged from 0.89 [CI: 0.57–1.37] (70) to 1.60 [CI: 1.13–2.27] (27) and the RR ranged from 0.98 [CI: 0.94–1.04] (9) to 1.49 [CI: 1.15–1.93] (57).

The superiority of ART reported in these reviews was mainly associated with clinical outcomes such as restoration survival, caries control, and reduced operative invasiveness, particularly in single-surface cavities. Reviews indicating better performance emphasized comparable or higher restoration longevity, effective caries arrest using high-viscosity glass ionomer cement, and a lower risk of pulpal complications due to selective tissue removal. These advantages are especially relevant in pediatric patients, as ART minimizes operative trauma, reduces the need for local anesthesia, and improves child cooperation without compromising clinical effectiveness.

Three SRs (33, 46, 77) evaluated chemical-mechanical caries removal in primary teeth. Two reported better performance compared with conventional treatments, while one found similar effects. Meta-analyses reported an MD of 0.57 [CI: 0.04–1.09] (33) and an OR of 0.33 [CI: 0.01–8.22] (46).

The improved performance of chemical-mechanical caries removal reported in these reviews was primarily related to reduced operative trauma, improved child cooperation, and preservation of sound dentin, rather than superior restoration longevity. These outcomes are particularly relevant in pediatric patients, where minimizing discomfort and the risk of pulp exposure is a key clinical objective.

Fifteen SRs (9, 15, 16, 43, 44, 47, 49, 51–53, 65, 77–79, 82) evaluated SDF in primary teeth. Thirteen SRs reported superior performance compared with conventional treatments, one reported similar effects, and one favored conventional treatments. Seven SRs conducted meta-analyses, reporting effect estimates ranging from MD −0.27 [CI: −0.46 to −0.07] (51) to OR 18.10 [CI: 3.89–84.15] (53), with RR values between 1.11 [CI: 1.03–1.20] (9) and 2.54 [CI: 1.67–3.85] (15).

Across the included reviews, the superiority of SDF was consistently associated with higher caries arrest rates and reduced lesion progression, rather than restorative outcomes. These effects were most pronounced in cavitated lesions and in community-based or non-invasive care settings, highlighting SDF's effectiveness as a caries management strategy rather than a conventional restorative intervention.

Two SRs (56, 62) reported that fluoride varnish showed similar effects to conventional treatments in primary teeth. Meta-analyses indicated OR values ranging from 0.99 [CI: 0.10–10.00] to 2.10 [CI: 0.52–9.00] (56), and an RR of 0.81 [CI: 0.62–1.06] (62).

Findings were consistent across lesion locations (proximal, occlusal, and buccal/lingual), suggesting comparable effectiveness rather than superiority over conventional approaches.

Six SRs (9, 28, 58, 59, 64, 66) evaluated the Hall technique in primary teeth. Four SRs reported superior performance compared with conventional treatments, while two reported similar outcomes. Meta-analyses reported OR values ranging from 1.06 [CI: 0.65–1.73] (66) to 8.35 [CI: 3.73–18.68] (58), and RR values from 0.18 [CI: 0.06–0.56] (59) to 1.30 [CI: 1.09–1.54] (9).

Overall, evidence favored the Hall technique, particularly for proximal lesions, with lower failure rates compared to conventional complete caries removal, although similar performance was observed when compared with alternative crown-based approaches.

Nine SRs evaluated selective excavation in primary teeth. Five reported superior performance compared with conventional treatments, while four reported similar effects. Meta-analyses showed OR values ranging from 0.10 [CI: 0.04–0.25] (80) to 4.43 [CI: 1.04–18.77] (58), and an RR of 0.33 [CI: 0.01–7.62] (61).

The reported advantages of selective caries excavation were mainly related to a reduced risk of pulp exposure and maintenance of pulpal vitality, while achieving restoration survival comparable to conventional complete caries removal. This approach emphasizes biological preservation over mechanical completeness, which is particularly advantageous in primary teeth.

Two SRs (38, 45) evaluated laser use for carious lesions in primary teeth. One reported better performance, while the other found similar effects compared with conventional treatments. Meta-analysis results showed RR values ranging from 0.30 [CI: 0.11–0.78] to 1.00 [CI: 0.99–1.01], indicating no consistent superiority.

Six SRs (50, 54, 56, 60, 67, 74) reported superior performance of resin infiltration compared with conventional treatments in primary teeth. Meta-analyses reported OR values ranging from 0.15 [CI: 0.06–0.39] (60) to 6.90 [CI: 2.00–24.00] (56), with consistent benefits observed particularly in proximal non-cavitated lesions.

Six SRs evaluated sealant use in primary teeth. Two reported superior performance, while four reported similar effects compared with conventional treatments. Meta-analyses showed OR values ranging from 0.23 [CI: 0.18–0.30] (74) to 5.00 [CI: 0.51–49.27] (58), and RR values between 0.67 [CI: 0.35–1.26] (38) and 1.06 [CI: 0.45–2.49] (81).

Evidence suggested greater effectiveness for proximal lesions, although overall findings indicated comparable rather than clearly superior outcomes.

Regarding ART, ten SRs assessed its effect in primary teeth; five of these had high confidence. Among those five, two concluded that ART performed better than conventional treatments, while three found similar outcomes. This aligns with a previous study (5), which defined ART success primarily as restoration survival without need for retreatment or pulpal complications, reporting higher success rates in single-surface cavities (86%) compared to multi-surface restorations, although the overall study quality was variable.

For chemo-mechanical caries removal, three SRs examined this approach in primary teeth, none with high confidence. Of these, two concluded that it performed better than conventional treatments, and one reported similar results. The observed advantage may be due to reduced trauma and greater tissue preservation, which improve child cooperation and reduce complications. Although promising, the lack of high-confidence reviews limits generalization.

Regarding SDF use in primary teeth, fifteen SRs addressed this intervention; seven had high confidence, and among these, six concluded that SDF performs better than conventional treatments, while one found similar results. This strengthens the high-quality evidence supporting SDF's strong caries-arresting effect in primary dentition (5), consistent with prior reviews suggesting that SDF is significantly more effective in halting caries progression compared to other treatments or placebo (4, 15).

For fluoride varnish, two SRs were identified, both with high confidence; all concluded that its performance is similar to conventional treatments in primary teeth. This suggests that although fluoride varnish is effective as a preventive or early-arrest measure, it does not clearly outperform other restorative or caries management techniques, particularly in advanced cavitations where its effect may be limited.

The Hall technique was examined in six SRs, all with high confidence: four reported better performances than conventional methods, and two found similar results. This agrees with evidence that the Hall technique can significantly reduce major failure rates compared to conventional restorations, as reported by BaniHani et al. (5). Furthermore, a recent SR showed that the Hall Technique is 49% more likely to succeed than conventional treatments and 80% more likely to succeed compared to direct restorations only (57). Its superior performance lies in completely sealing the carious lesion without extensive removal, creating an anaerobic environment that inhibits bacterial progression (84). However, in some contexts, its performance was similar to that of conventional stainless-steel crowns, suggesting that the advantage may depend on lesion type, operator, or clinical setting.

Selective caries excavation was evaluated in nine SRs; four had high confidence. Among these, two reported better performances and two similar results compared to conventional methods. This indicates that selective excavation is a promising, though not universally superior, option. The probable explanation is that it minimizes pulpal risk by leaving affected but firm dentin and reduces operative intervention, improving restoration longevity—particularly important in primary teeth where tooth preservation is prioritized.

For laser use, two SRs were identified; one had high confidence and concluded that laser performance was similar to conventional treatments. This suggests that while technically feasible, laser use has not consistently shown clear superiority—possibly due to factors such as cost, technical complexity, need for specialized equipment, and limited evidence in primary teeth.

Resin infiltration was analyzed in six SRs, four with high confidence, all concluding that resin infiltration performs better than conventional methods. Although most studies have focused on non-cavitated proximal lesions in permanent teeth, these findings suggest a positive transfer to the primary dentition. This could be explained by the technique's early action on porous lesions, inhibiting progression and avoiding the need for more invasive intervention.

Finally, for sealants in carious lesions in primary teeth, four SRs with high confidence reported that one found better performance while the other three found similar results compared to conventional methods. This indicates that sealant use in primary teeth remains a valid option, especially for prevention or management of early lesions, though in deeper cavities it may not outperform other restorative or minimally invasive approaches.

Overall, the apparent benefits of minimally invasive interventions are not uniform across techniques and are sensitive to the methodological quality of the underlying evidence. Consequently, the most reliable inferences in this umbrella review are derived from interventions supported by high-confidence and low-risk systematic reviews, whereas findings based predominantly on low or critically low-confidence reviews should be considered promising but uncertain.

From a comparative clinical perspective, each minimally invasive approach offers distinct advantages depending on lesion characteristics and patient-related factors. Silver diamine fluoride (SDF) presents the strongest evidence for caries arrest, particularly in cavitated lesions and community-based or non-cooperative pediatric settings, due to its high efficacy, low cost, and minimal technical requirements. The Hall technique demonstrates superior survival outcomes in proximal lesions by sealing caries without tissue removal, making it especially suitable for young or anxious children. Resin infiltration is particularly advantageous for non-cavitated proximal lesions, as it arrests lesion progression at an early stage while preserving tooth structure. Atraumatic restorative treatment (ART) is most effective in single-surface cavities and resource-limited environments, offering outcomes comparable to conventional restorations. Selective caries excavation minimizes the risk of pulp exposure while maintaining restoration longevity. In contrast, fluoride varnish and laser-based interventions show more limited or comparable effectiveness and mainly support preventive or adjunctive roles rather than definitive treatment of established lesions.

The differentiated advantages of each minimally invasive strategy underscore the importance of tailoring clinical decisions to injury severity, child cooperation, and available resources. The findings of this review suggest that minimally invasive strategies play a significant role in managing caries in primary dentition, highlighting the strong support for SDF, whose efficacy has been consistently demonstrated in high-quality reviews, suggesting that clinicians may consider its use in carious primary teeth, particularly when supported by high-confidence evidence and aligned with individual clinical context. Likewise, the Hall technique and resin infiltration show similar levels of benefit, allowing for less invasive treatments, reduced need for anesthesia, and more favorable clinical experiences for children.

Based on the certainty and consistency of the available evidence, minimally invasive interventions can be differentiated according to their level of clinical support. Silver diamine fluoride (SDF), the Hall technique, and resin infiltration are supported by the most robust evidence, as these approaches were consistently evaluated in high-confidence systematic reviews with low risk of bias and demonstrated superior or equivalent outcomes compared with conventional treatments. SDF is particularly supported for caries arrest in cavitated lesions and in non-cooperative children or community-based settings. The Hall technique shows strong support for proximal and multi-surface lesions, with high restoration survival and reduced major failure rates, while resin infiltration is best supported for non-cavitated proximal lesions, where it effectively arrests lesion progression while preserving tooth structure. In contrast, interventions such as atraumatic restorative treatment (ART), selective caries excavation, sealants, fluoride varnish, laser-based therapies, and chemical-mechanical caries removal are supported by more heterogeneous or lower-quality evidence and should therefore be considered context-dependent or adjunctive options rather than universally preferred first-line treatments.

However, variability in the evidence, such as for ART or selective excavation, indicates that not all minimally invasive methods are equally supported. Although the study overlap is low, heterogeneity and bias risk still limit some conclusions. Therefore, professionals should interpret findings cautiously and communicate to parents/guardians that, while the trend favors minimal intervention, not all methods have the same level of evidence.

In resource-limited settings, procedures such as SDF or ART can expand access to treatment, reduce lesion progression, and lower associated costs. In pediatric dental practice, it remains essential to consider each patient's individual context (cooperation level, lesion extent, resource availability) and adopt a personalized approach. Finally, although minimally invasive techniques show great potential and comparable or superior efficacy to conventional treatments, they do not completely replace them, especially in cases of extensive lesions or pulpal involvement.

Importantly, clinical decision-making should explicitly incorporate evidence certainty. Interventions supported by high-confidence systematic reviews may be preferentially considered, whereas techniques supported by heterogeneous or lower-quality evidence should be individualized and discussed with caregivers in terms of potential benefits and uncertainty.

From a research standpoint, this review identifies several relevant gaps. Despite the low overlap, the distribution of confidence across reviews indicates the need for more rigorous studies, particularly for techniques with limited evidence (e.g., laser and chemo-mechanical removal). The existence of nine critically low-confidence reviews reinforces this need.

Moreover, since 25 SRs showed a low risk of bias but 24 had a high risk, future SRs should improve design, reporting, and bias assessment. There is a need for multicenter clinical trials with medium- and long-term follow-up comparing minimally invasive and conventional techniques in primary teeth.

Future studies should also explore patient- and caregiver-centered outcomes (e.g., pain, anxiety, quality of life), not only clinical success or restoration longevity. As noted by BaniHani et al. (5), reports often focus on clinical outcomes without considering the child's experience.

Finally, it is recommended to develop evidence-based clinical guidelines adapted to pediatric dental care settings, to standardize the integration of minimally invasive techniques with conventional management when appropriate. Improving the methodological rigor and transparency of future systematic reviews is essential to strengthen evidence synthesis in pediatric minimal intervention dentistry.