F1000Research F1000Research 2046-1402 F1000 Research Limited London, UK 10.12688/f1000research.136653.2 Research Article Articles Preventive efficacy of 38% silver diamine fluoride and CPP-ACP fluoride varnish on molars affected by molar incisor hypomineralization in children: A randomized controlled trial

[version 2; peer review: 1 approved, 1 not approved]

 Al-Nerabieah Zuhair Conceptualization Data Curation Formal Analysis Funding Acquisition Investigation Methodology Resources Validation Visualization Writing – Original Draft Preparation Writing – Review & Editing https://orcid.org/0000-0003-1843-1776 a 1 AlKhouli Muaaz Data Curation Formal Analysis Investigation Methodology Resources Validation Writing – Original Draft Preparation 1 Dashash Mayssoon Conceptualization Formal Analysis Funding Acquisition Project Administration Supervision Validation Visualization Writing – Original Draft Preparation Writing – Review & Editing https://orcid.org/0000-0002-9877-3217 1 Pediatric Dentistry, Damascus University, Damascus, Damascus Governorate, Syria zuhairmajid@gmail.com

No competing interests were disclosed.

 21 2 2024 2023 12 1052 13 2 2024 Copyright: © 2024 Al-Nerabieah Z et al. 2024 This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Background

This randomized controlled trial aimed to compare the efficacy of silver diamine fluoride (SDF) and Casein Phosphopeptide-Amorphous Calcium Phosphate fluoride Varnish (CPP-ACPFV) in preventing caries development, enamel breakdown, and sensitivity on molars affected by molar incisor hypomineralization (MIH) in children.

 Methods

A total of 100 children aged 6 to 9 years were enrolled in the study with two contralateral permanent molars mildly affected by MIH. Affected molars were randomly and equally assigned to receive either SDF or CPP-ACPFV treatment. The interventions were applied at four different time points (baseline, 3, 6, 9 months), and the incidence of caries, caries progression, enamel breakdown, and sensitivity were assessed.

 Results

The findings of this study revealed significant differences in the incidence of caries between the groups treated with SDF and CPP-ACPFV ( P-value < 0.05). Similarly, there was a significant difference in caries progression between the two groups ( P-value < 0.05). However, no significant differences were observed in enamel breakdown scores between the treatment groups, as the majority of teeth in both groups exhibited a score of 0. Furthermore, there were no significant differences in sensitivity between the treatment groups throughout the study period.

 Conclusions

In conclusion, the results of this study provide evidence that molars treated with SDF demonstrated a lower incidence of caries and a higher rate of caries arrest compared to those treated with CPP-ACPFV. Both interventions showed promise in preventing enamel breakdown and improving sensitivity. These findings highlight the potential of SDF and CPP-ACPFV as effective treatments for caries prevention and management, emphasizing the importance of early intervention and appropriate dental care strategies in maintaining oral health.

 Trial registration

ISRCTN54243749 (13/01/2022).

 Molar-Incisor Hypomineralization Silver Diamine Fluoride MI Varnish Caries prevention Enamel breakdown Sensitivity Children Damascus University Damascus University funded this research. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript. Amendments from Version 1

In this revised manuscript, notable changes have been made to enhance clarity and precision. The title has been amended. Specifically, the brand name of MI varnish has been replaced with its generic name, CPP-ACP Fluoride varnish (CPP-ACPFV), ensuring consistency and transparency in terminology. Additionally, detailed information about the content of both SDF and CPP-ACPFV has been incorporated into the methods section, providing readers with a comprehensive understanding of the interventions utilized in the study. Furthermore, the training and calibration of outcome examiners have been explicitly outlined in the methods section, underscoring the rigorous methodology employed to ensure reliability and accuracy in data collection. Moreover, evidence supporting the reliability and validity of Reveal loupes in caries detection has been elucidated in the discussion, bolstering the credibility of the findings. Lastly, limitations arising from the use of a split-mouth design have been thoughtfully discussed in the limitations section, offering a transparent assessment of potential biases inherent in the study design. These enhancements collectively contribute to a more robust and informative manuscript, facilitating clearer interpretation and dissemination of the research findings. In this revised version of the manuscript, two new figures have been uploaded to replace the existing ones, with appropriate adjustments made to reflect the change from MI varnish to CPP-ACPFV. Additionally, a new table has been introduced into the text as Table 1, necessitating updates to the subsequent numbering of tables throughout the document. Furthermore, a new reference has been added to the article.

 Introduction

Molar incisor hypomineralization (MIH) is a common dental condition that affects the quality of life of children. 1 It is characterized by enamel hypomineralization and discoloration of one or more permanent first molars and incisors, resulting in increased caries and post-eruptive enamel breakdown. 2 This can cause a range of oral health problems, including pain and sensitivity, which can affect a child's ability to eat, sleep, and participate in daily activities. 3

MIH has become an increasingly recognized problem for researchers and a challenging issue for pediatric dentists. With prevalence rates ranging from 2% to 14% across different populations and diagnostic criteria, MIH poses significant challenges in the field of pediatric dentistry (PD). 4 This condition is believed to have a multifactorial etiology, with potential contributing factors including prenatal and perinatal influences, systemic diseases, and environmental exposures. 5

Recent research has shed light on the high prevalence of MIH in specific populations. A noteworthy study conducted in Syria revealed a staggering prevalence rate of 39.9% among Syrian children. 6 This finding underscores the urgency of addressing MIH and its impact on oral health in affected individuals. Understanding the prevalence of MIH in different populations provides valuable insights into the extent of the problem and emphasizes the need for effective preventive and management strategies. 7

Despite the growing recognition of MIH as a significant public health issue, there is limited research available on effective treatments for this condition. 8 The impact of MIH on children's quality of life highlights the need for effective treatments that can prevent or mitigate the effects of this condition. 9

Although routine oral care practices and fluoride are effective in preventing caries, these methods may not be sufficient in managing MIH. 8 MIH-affected teeth have altered enamel structures and are more porous, making them more prone to caries and enamel breakdown than non-affected teeth. The enamel's increased porosity allows bacteria to penetrate and initiate caries formation, leading to early cavitation and further enamel breakdown. 10

The consequences of untreated MIH can range from impaired oral function and increased risk of caries, to decreased self-esteem and social isolation. 11 As a result, it is important to identify treatments that can effectively prevent or manage MIH and improve the oral health and quality of life of affected children. 12

The challenges posed by MIH have led to the development of various preventive and therapeutic measures, such as the use of casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) and silver diamine fluoride (SDF). 13 MI Varnish™ is a product that contains 5% NaF and 2% CPP-ACP, which have been shown to enhance enamel remineralization and reduce sensitivity in MIH-affected teeth. 14

On the other hand, SDF is a minimally invasive and cost-effective approach for arresting and preventing carious lesions. 15 SDF works by inducing the formation of a silver-protein complex and a calcium fluoride-like layer, which can kill cariogenic bacteria and promote remineralization. 16 SDF is effective in reducing caries incidence and arresting cavitated lesions in primary and permanent teeth. 17 , 18 Nevertheless, the efficacy of SDF for preventing caries in MIH-affected molars remains unclear, and there is a lack of studies investigating the use of SDF as a preventive measure for MIH-affected molars.

In this context, the effectiveness of SDF and CPP-ACP in preventing or managing the outcomes of MIH has become an important area of investigation. 19 While both SDF and CPP-ACP have been shown to have potential benefits in managing this condition, it is important to understand the relative efficacy of these treatments in a well-controlled, randomized clinical trial. The results of such a trial can inform the development of evidence-based guidelines for the management of MIH in children, and help to ensure that children receive the most effective, and appropriate oral health care.

Therefore, this study aimed to compare the effectiveness of SDF and Casein Phosphopeptide-Amorphous Calcium Phosphate Fluoride Varnish (CPP-ACPFV) in preventing the development and progression of caries and post-eruptive enamel breakdown in children's molars affected by MIH.

 Methods Ethical considerations

Ethical approval was obtained from the Research Ethics Committee at Damascus University ‘2984’ dated 19/09/2021. Written informed consent was obtained from the parents or legal guardians of all participants before enrolment in the study. The trial was registered on 13/01/2022 at ISRCTN with the following number ( ISRCTN54243749). Furthermore, the study was designed and reported according to the Consolidated Standards of Reporting Trials (CONSORT) statement criteria to ensure rigorous and transparent reporting of the study methodology and results. 20

Study design and setting

This study was a randomized controlled clinical trial, double-blinded with a split-mouth design, conducted in a paediatric dental department at Damascus University, Syria. This study was performed at the period from Jan 2022 to Feb 2023.

 Sample size determination

The sample size was calculated using G*Power software version 3.1.9.4. Based on the results of a previous study, 21 the expected mean difference in the International Caries Detection and Assessment System (ICDAS-II) scores between the two groups was estimated to be 2.2 with a standard deviation of 2.0. The power of the study was set at 90%, with an alpha level of 0.05, and a 20% allowance for dropouts. The final sample size was 100 children (200 permanent molars) between the ages of 6 and 9 years.

 Inclusion and exclusion criteria

The study's inclusion criteria were carefully defined to ensure a homogeneous sample of participants. Only children between the ages of 6 and 9 years, with two contralateral permanent molars mildly affected by MIH and without any prior treatment on the affected molars, were included. The molars were also required to be fully erupted, with no overlapping gingiva. Additionally, children were required to express their willingness to participate in the study.

Exclusion criteria comprised children with systemic diseases, a history of orthodontic treatment or extractions, silver sensitivity, and allergy to fluoride or milk proteins. Children with other enamel developmental disorders, such as fluorosis and amelogenesis imperfecta, were also excluded from the study. By implementing these criteria, the study aimed to establish a clear and consistent cohort of participants for analysis.

 Randomization and blinding methods

In this split-mouth study, randomization was performed based on two factors: the type of material (SDF/CPP-ACPFV) and the side of the mouth (left/right). To determine the order of application and the tooth to be treated, each eligible patient drew twice from opaque envelopes. The first draw determined the material to be applied first, and the second draw determined the tooth to be treated with the chosen material.

To ensure consistency, the same tooth received the same treatment throughout the study. To minimize any potential bias, both the children and the outcome assessors were blind to the treatment allocation. The children were instructed not to reveal their treatment to the assessors, and the assessors were instructed not to inquire about it. Both SDF and CPP-ACPFV were applied at baseline, and after 3, 6, and 9 months.

 Materials and procedure

The composition of the commercial products, along with their respective lot numbers, is outlined in Table 1 for reference.

Details of materials used in the study.
Material Commercial product Manufacture Active ingredients Excipient ingredients Lot number Source
38% SDF Advantage arrest Elevate Oral Care, USA 25% silver ions and 5% fluoride ions dissolved in an 8% ammonia solution Water, FD&C Blue No 1 17042 Dental supplier, USA
CPP-ACPFV Mi Varnish GC Corporation, Itabashi-Ku, Tokyo, Japan 5% Sodium fluoride, 2% Casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) Polyvinyl acetate (synthetic resin), Ethanol, Hydrogenated rosin, 1–5% Silicon dioxide, Flavor 191203A Dental supplier, UAE

An experienced investigator (ZN) was responsible for the examination of children visiting the PD department for MIH, utilizing the European Association of Paediatric Dentistry (EAPD) criteria. 13 Parents of eligible children were presented with an informed consent form and an informational brochure regarding the study, with the understanding that participants had the right to withdraw at any time. Only children with two contralateral molars displaying mild MIH lesions were enrolled in the study, characterized by demarcated enamel opacities without caries and enamel breakdown, and had only induced sensitivity to external stimuli.

At the initial visit, both children and parents were provided with dietary advice and oral hygiene instructions. Additionally, participants were given toothbrushes and toothpaste containing 1000-ppm fluoride. In the subsequent visit, sensitivity testing was performed on both affected molars using an air syringe. The air syringe was placed close (1 cm) to the occlusal surface of the affected tooth for one second, and children's response to this stimulus was evaluated using the Schiff Cold Air Sensitivity Scale (SCASS). 22 The process was then repeated for the other affected tooth. Furthermore, the Decayed, Missing due to caries, and Filled Teeth (DMFT)/dmft index developed by the World Health Organization was also calculated after documenting the decayed, missing, and filled teeth for both permanent and primary teeth.

SDF (Advantage Arrest, Elevate Oral Care, USA) and CPP-ACPFV (Mi Varnish, GC, Japan) were then applied in the same visit, with the order and side of the application being determined at random by the child. The application procedure for both materials was standardized. Initially, the teeth were cleaned using gauze, and a dry field was maintained using cotton rolls. Subsequently, a single drop of either SDF or CPP-ACPFV was placed in a disposable plastic dish. The material of choice was then applied to the affected tooth using a microbrush applicator (MRG400, Henry Schein, USA) for a duration of one minute. Finally, a layer of petroleum gel (VASELINE, Unilever, USA) was evenly spread over the entire tooth to complete the application process. In addition, parents were provided with specific instructions that participants should avoid the consumption of food or hot beverages for a period of one hour following the application of the preventive materials. This precaution was implemented to ensure the optimal retention and effectiveness of both SDF and CPP-ACPFV.

Sensitivity testing and application of the study materials were conducted again during follow-up visits after 3, 6, 9, and 12 months.

 Assessment of outcome measures

Two pediatric dentist experts were recruited to perform the outcome measures assessment. Prior to the initiation of this study, both examiners underwent comprehensive training and calibration sessions on the International Caries Detection and Assessment System (ICDAS II) criteria and the use of Reveal fluorescence dental loupes. The training regimen encompassed theoretical instruction on ICDAS II and fluorescence in the detection of carious lesions, as well as practical, hands-on training sessions using both carious and sound extracted primary molars. This rigorous training protocol ensured that both examiners were proficient and consistent in their assessment methodologies, thereby enhancing the reliability and validity of the study outcomes.

The primary outcome measures for this study included assessing caries development and caries activity. Caries development was evaluated using the International Caries Detection and Assessment System (ICDAS) criteria and which categorizes tooth surfaces as either sound or carious. A score of 0 indicated a sound surface without any evidence of caries, while a score of 1 indicated the presence of any detectable signs of caries, regardless of severity. Additionally, caries activity was assessed using Reveal fluorescence dental loupes (Design for vision, USA) and scored as either active or arrested. These scores were recorded at 3, 6, 9, and 12 months from the baseline.

Another primary outcome measure was the assessment of Post eruptive Enamel Breakdown (PEB), which was scored according to the criteria proposed by Ghanim et al. (2017). 23 PEB scores were recorded at the same time points mentioned previously, and each molar was given a score of 0 for no visible enamel breakdown, 1 for less than one-third of the tooth affected, 2 for at least one-third but less than two-thirds of the tooth affected, and 3 for at least two-thirds of the tooth affected.

In this study, the secondary outcome measure was changes in sensitivity, which were assessed using the SCASS. This scale is a validated tool used to evaluate tooth sensitivity in response to cold stimuli. 22 The dental professional responsible for conducting the cold air sensitivity test underwent comprehensive training to ensure proficiency and consistency in test administration. This training encompassed detailed instructions on the correct positioning of the dental air syringe, the duration and intensity of the air stream, and the standardized distance from which the air was delivered to the tooth’s occlusal surface. Moreover, the training emphasized the importance of clear communication with the children to ensure their understanding of the procedure and to encourage accurate reporting of any sensations experienced during the test.

Additionally, the dental professional received guidance on recognizing and documenting the various response categories outlined in the SCASS scale, thereby ensuring uniform interpretation and scoring of sensitivity levels. Overall, the specific training regimen aimed to equip the dental professional with the necessary skills and knowledge to conduct the sensitivity test reliably and consistently across all study participants.

Before the testing, children were informed about the procedure and what to expect. They were instructed to report any discomfort or sensation experienced during the test.

During the assessment, a standard dental air syringe was used to deliver a stream of air for 1 second at a distance of 1 cm and perpendicular to the occlusal surface of the tooth. The subject's response to this stimulus was observed and evaluated using the SCASS Scale. The scale consists of four response categories: 0 represents no response to the stimulus, 1 indicates no response to the stimulus but the subject considers it painful, 2 signifies a response to the stimulus with the subject moving away from it, and 3 indicates a response to the stimulus with the subject moving away and requesting immediate discontinuation. The subject's response was recorded and scored accordingly, in which a higher score indicates a greater sensitivity to cold stimuli.

Sensitivity scores were recorded at 3, 6, 9, and 12 months from the baseline, allowing for the evaluation of changes in sensitivity over time. Additionally, the dental professional performing the test at follow-up was blinded to the results from the earlier period to prevent any bias in the assessment of sensitivity changes over time.

 Data analysis and examiner reliability

Data were analyzed using IBM SPSS version 23 (IBM Corp., Armonk, USA). Descriptive data including the distribution of affected molars were demonstrated. Chi-squared test was used to analyze the difference between the two studied groups regarding the development of caries in the MIH molars and the activity of the caries lesions at each time point (3 months, 6 months, 9 months, and 12 months). In addition, repeated measures ANOVA test was performed to detect if there was a difference between the different time points in each group separately. However, the Bonferroni test was the post hoc test used to determine where the difference was. The P-value of 0.05 was considered the level of significance. The mean rank of the scores of enamel breakdown and SCASS were calculated to conduct the Mann-Whitney U test to reveal the difference between the two groups at each time point. Similarly, repeated measures ANOVA test was performed to detect if there was a difference between the different time points in each group. Wilcoxon signed Rank test was used as a post hoc test to detect where the difference was. Friedman test was used to reveal the difference between the four-time points regarding the mean rank of enamel breakdown scores in both groups. The intra-examiner reliability was assessed through the re-examination of 10% of the participants one week after the initial examination and was found to be high ( Kappa coefficient = 0.86). The inter-examiner reliability was assessed by independent examination of a sample of participants and was found to be high ( Kappa coefficient = 0.87).

 Results

A total of 100 children were enrolled in this trial (42 girls and 58 boys) with a mean age of 7.6 ± 1.4. Each child had two contralateral permanent 1 st molars affected with mild MIH. 24 The distribution of the molars involved in the study is summarized in Table 2.

The distribution of the molars involved in the study.
Boys Girls Total
Maxillary molars 26 44 70 (35%)
Mandibular molar 90 40 130 (65%)
Total 116 (58%) 84 (42%) 200 (100%)

The mean and standard deviation of dmft and DMFT indices were 4.37 ± 1.40 and 0.30 ± 0.63, respectively. The proportion of caries-free children was 11.3%. Table 3 shows the number of molars that were affected by caries in each group and for the four studied time points (after 3, 6, 9, and 12 months). The chi-squared test showed that carious molars were less in the SDF group than in the MI group with a statistically significant difference ( P-value < 0.05) in each follow-up schedule.

The difference between groups and within groups regarding caries development.
Intervention 3 months 6 months 9 months 12 months Sum of squares F-value P-value
SDF Caries (number of teeth) 11 15 21 23 91 0.42 0.183
No caries (number of teeth) 89 85 79 77
CPP-ACPFV Caries (number of teeth) 33 39 44 49 140.74 0.32 0.111
No caries (number of teeth) 67 61 56 51
Chi-squared 2.621 4.489 7.562 9.141
P-value 0.002 * 0.034 * 0.023 * 0.001 *

SDF: Silver diamine fluoride.

Significant difference.

On the other hand, repeated measures ANOVA showed that there was no statistically significant difference in the development of caries between the four-time points in neither the SDF group nor the MI group ( P-value > 0.05).

Moreover, the chi-squared test showed that the percentages of arrested caries were higher in the SDF group than in the MI group with a statistically significant difference in months 6, 9, and 12 ( P-value < 0.05). This means that our findings revealed that SDF is better than CPP-ACPFV in arresting the developed caries lesions, especially after 6 months of application ( Figure 1). Additionally, repeated measures ANOVA test detected that there was a statistically significant difference between the four-time points in arresting caries in both studied groups ( Table 3).

The difference between the percentage of active caries in both groups.

(SDF: Silver diamine fluoride, CPP-ACPFV: Casein Phosphopeptide-Amorphous Calcium Phosphate Fluoride Varnish).

Bonferroni post hoc test indicated that the difference was statistically significant between the 3 months follow-up and the other time points only.

Regarding the enamel breakdown detected in each group, the Mann-Whitney U test showed that there was no statistically significant difference between the SDF and MI groups at each time point. This means that both SDF and CPP-ACPFV were effective in the prevention of enamel breakdown of MIH molars ( Table 4).

The difference between groups and within groups regarding arresting the carious lesions.
Intervention 3 months 6 months 9 months 12 months Sum of squares F-value P-value
SDF Active caries (number of teeth) 11 (100%) 6 (40%) 5 (25%) 3 (13%) 222 1.22 0.002 *
Arrested caries (number of teeth) 0 (0%) 9 (60%) 15 (75%) 20 (87%)
CPP-ACPFV Active caries (number of teeth) 33 (100%) 28 (71.7%) 29 (65%) 32 (65%) 173.75 1.45 0.001 *
Arrested caries (number of teeth) 0 (0%) 11 (28.3%) 15 (34%) 17(34.7%)
Chi-squared 0.193 1.431 4.507 9.252
P-value 0.660 0.021 * 0.034 * 0.002 *

SDF: Silver Diamine fluoride.

Significant difference.

Friedman test indicated that there was no statistically significant difference between the four-time points regarding the mean rank of enamel breakdown scores in neither the SDF group nor in the MI group ( P-value= 0.513, 0.221 respectively) ( Table 5).

Mann-Whitney U test to study the difference between the groups regarding enamel breakdown.
Enamel breakdown 3 months 6 months 9 months 12 months
SDF CPP-ACPFV SDF CPP-ACPFV SDF CPP-ACPFV SDF CPP-ACPFV
0 (number of teeth) 99 100 98 99 95 97 92 91
1 (number of teeth) 1 0 0 1 2 1 2 4
2 (number of teeth) 0 0 2 0 2 0 4 3
3 (number of teeth) 0 0 0 0 1 2 2 2
Mean rank 11 12 10 12 12 13 14 15
P-value 0.732 0.453 0.231 0.322

SDF: Silver diamine fluoride.

As shown in Table 6, the Mann-Whitney U test similarly showed that there was no statistically significant difference between the SDF group and the MI group regarding the Schiff Cold Air Sensitivity Scale at each time point. However, the Friedman test indicated that the difference between the five-time points (baseline, 3 months, 6 months, 9 months, and 12 months) was statistically significant in both SDF and MI groups.

Mann-Whitney U test to study the difference between the groups regarding SCASS.
SCASS Baseline 3 months 6 months 9 months 12 months
SDF CPP-ACPFV SDF CPP-ACPFV SDF CPP-ACPFV SDF CPP-ACPFV SDF CPP-ACPFV
0 (number of teeth) 55 56 69 67 80 77 83 83 84 83
1 (number of teeth) 33 32 25 26 18 19 17 15 16 15
2 (number of teeth) 7 6 4 5 2 3 0 2 0 2
3 (number of teeth) 5 6 2 3 0 1 0 0 0 0
Mean Rank 16 15 13 15 12 13 11 11 11 10
P-value 0.454 0.421 0.309 0.288 0.122

SCASS: Schiff cold air sensitivity scale; SDF: Silver diamine fluoride.

Wilcoxon Signed Rank test revealed that in both SDF and MI groups, there was a statistically significant difference between the baseline and 3 months (P-value = 0.002, 0.001, respectively), between the baseline and 6 months of application (P-value = 0.001, 0.021, respectively) and between the 3 months and 6 months of application (P-value = 0.011, 0.001, respectively). However, there was no statistically significant difference between 9 months and 12 months neither in the SDF group nor in the MI group. Figure 2 shows the change in the mean rank of SCASS between the groups and between the time points.

The change in the mean rank of Schiff cold air sensitivity scale SCASS between the groups and between the time points.

(SDF: Silver diamine fluoride, CPP-ACPFV: Casein Phosphopeptide-Amorphous Calcium Phosphate Fluoride Varnish).

 Discussion

This study aimed to evaluate and compare the preventive efficacy of SDF and CPP-ACPFV in molars affected by MIH among children aged 6–9 years. The results of this study indicate that molars treated with SDF had a significantly lower incidence of caries and a higher rate of caries arrest compared to those treated with CPP-ACPFV. Both SDF and CPP-ACPFV demonstrated the ability to prevent enamel breakdown and improve sensitivity, with no statistically significant difference between the two treatments.

This age group was selected based on several considerations related to the nature of MIH and the developmental stage of affected teeth.

MIH commonly manifests during the eruption of the first permanent molars, which typically occurs around the age of 6 years. 25 By including children within the age range of 6–9 years, the study focused on a critical period when MIH-affected molars are fully erupted and accessible for examination and treatment.

Furthermore, children within this age range are more likely to comply with study protocols and express their willingness to participate actively. They have a better ability to understand and cooperate during dental examinations and treatments, enhancing the feasibility of the study. Additionally, by targeting this age group, the study aimed to address the preventive needs of children at a crucial developmental stage when early intervention can have a significant impact on long-term oral health outcomes. 26 , 27

The utilization of the European Academy of Pediatric Dentistry (EAPD) criteria for the diagnosis and classification of MIH played a significant role in this study. The EAPD criteria have been widely accepted and recommended as the gold standard for the diagnosis and classification of MIH, providing a standardized approach to ensure consistency and comparability among studies and clinical practice. 13

In addition, the implementation of the EAPD criteria for inclusion ensured the homogeneity of the sample and the accurate identification of participants with MIH. By applying these criteria, the researchers could confidently select children with mild MIH-affected molars, minimizing potential confounding factors and enhancing the validity of the study results.

In the context of this study, the ICDAS-II criteria were employed to detect and assess caries incidence in the molars affected by MIH. ICDAS-II is considered a widely recognized and standardized method for detecting and assessing caries. 28 It provides a comprehensive and detailed classification system that allows for the consistent evaluation and diagnosis of caries lesions based on their visual appearance.

In addition, the caries activity outcome measure was assessed using Reveal fluorescence dental loupes, and the results showed that SDF had a higher percentage of arresting caries compared to CPP-ACPFV, and this difference was found to be statistically significant.

The use of Reveal fluorescence dental loupes for evaluating caries activity in this study provided an additional objective measure to assess the effectiveness of the preventive treatments. 29 These dental loupes utilize fluorescence technology to detect the presence of caries activity based on the fluorescence emission of bacterial metabolites in the oral cavity. 30

The inclusion of Reveal fluorescence dental loupes offered several advantages in this study. Firstly, it is a non-invasive and painless procedure, making it well-suited for use in pediatric patients. Secondly, the immediate results provided a real-time assessment of caries activity, enabling prompt decision-making regarding treatment interventions. Additionally, the qualitative nature of the fluorescence measurements contributed to more objective and standardized evaluations, reducing subjectivity in the assessment process. 29 , 30

Furthermore, a recent study by Steier and colleagues, focusing on fluorescent enhanced theragnosis through Reveal Vision glasses for the diagnosis of caries progress. Their study revealed a substantial kappa score of 0.706, indicating significant reproducibility for the given diagnostic technique. 31

The superior performance of SDF in preventing and arresting caries can be attributed to its unique mechanism of action. SDF works by inducing the formation of a silver-protein complex and a calcium fluoride-like layer, which effectively kills cariogenic bacteria and promotes remineralization. 16 This antimicrobial and remineralization effect of SDF is particularly beneficial in managing caries in MIH-affected molars, where the enamel is more susceptible to demineralization and cavitation. 32

The significant difference observed between SDF and CPP-ACPFV suggests that SDF may be a more effective preventive treatment option for caries in MIH-affected molars. These findings align with previous studies that have demonstrated the superiority of SDF in caries prevention and arrest, particularly in primary and permanent teeth. 33 , 34

Despite the growing interest in the effectiveness of Casein Phosphopeptide-Amorphous Calcium Phosphate (CPP-ACP) in preventing caries development and progression, there is still ongoing research in this area. In line with previous studies, our research findings support the notion that CPP-ACP demonstrates efficacy in preventing caries. A recent systematic review and meta-analysis conducted by Sharda et al. (2020) investigated the efficacy of CPP-ACP complex and topical fluoride (TF) in managing caries. 35 The study revealed that while CPP-ACP showed superiority over TF monotherapy in remineralizing existing lesions and exhibiting a stronger antibacterial effect, it did not demonstrate greater efficacy in preventing caries incidence.

The findings of Sharda et al.'s systematic review highlight the limitations of CPP-ACP in terms of preventing the occurrence of new carious lesions. Although CPP-ACP has shown promise in remineralizing existing lesions and exerting antibacterial properties, its impact on preventing caries incidence appears to be limited. 35

Furthermore, a recent study showed that a single topical application of the GC Tooth mousse (CPP-ACP) does not affect increasing the salivary pH and salivary flow rate which are great factors in caries prevention. 36

On the other hand, both SDF and CPP-ACPFV showed comparable performance in preventing enamel breakdown (PEB). This indicates that both materials were effective in preserving the integrity of the enamel surface and preventing further deterioration of the affected teeth. The lack of significant difference in PEB outcomes between the two groups suggests that both treatments have a similar capacity to stabilize the enamel and prevent its breakdown.

Furthermore, both SDF and CPP-ACPFV demonstrated improvement in sensitivity, with no significant difference observed between the two groups. This indicates that both materials were effective in alleviating the sensitivity commonly associated with MIH-affected molars. The reduction in sensitivity can greatly improve the quality of life for affected children by minimizing discomfort and facilitating normal oral function.

The efficacy of CPP-ACP in preventing enamel breakdown and improving sensitivity has been investigated in several studies, allowing for a comparison of results. In our study, we found that CPP-ACPFV demonstrated effectiveness in preventing enamel breakdown. This finding is consistent with previous research that has reported positive outcomes with the use of CPP-ACPFV as a preventive treatment for enamel hypomineralization.

A notable investigation conducted by Bakkal et al. (2017) aimed to assess the efficacy of 10% CPP-ACP cream in enhancing the mineral content of hypomineralized enamel. The outcomes of their study demonstrated a marked improvement in mineralization, as well as enhancements in enamel morphology and reductions in porosities. 37 This highlights the positive impact of CPP-ACP cream on addressing the deficiencies in hypomineralized enamel.

Moreover, Cardoso-Martins et al. (2022) conducted a study that further supports these findings. Their investigation focused on evaluating the effects of CPP-ACP tooth mousse on the mineral density and organization of hypomineralized enamel. The results demonstrated significant improvements in both mineral density and the overall structural organization of the affected enamel following treatment with CPP-ACP tooth mousse. 38 This study reinforces the potential of CPP-ACP as a valuable therapeutic option for ameliorating the compromised enamel associated with hypomineralization.

Regarding the improvement of sensitivity, our study demonstrated that CPP-ACPFV was effective in alleviating sensitivity associated with MIH. Similarly, a systematic review by Somani et al. (2022) analyzed multiple studies and concluded that CPP-ACP products showed promising results in reducing sensitivity in MIH-affected teeth. 8 They reported a significant reduction in sensitivity scores following the application of MI Varnish.

Overall, the results of our study, along with the findings of previous research, support the use of CPP-ACPFV as an effective intervention for preventing enamel breakdown and improving sensitivity in individuals with MIH.

Several limitations should be considered when interpreting the findings of this study. Firstly, the study sample was drawn from a specific population of children aged 6 to 9 years with MIH, which may restrict the generalizability of the results to other age groups or individuals with different characteristics. Further research involving diverse populations is necessary to validate the findings across a broader range of individuals affected by MIH.

In addition, the study had a relatively short follow-up period, which may limit the ability to assess the long-term effectiveness and durability of the preventive treatments. Hence, longer follow-up periods would provide valuable insights into the sustainability of the interventions over time.

Furthermore, it’s important to acknowledge that the split-mouth design used in the study may introduce certain limitations. Firstly, factors such as variations in saliva flow and oral hygiene practices could potentially confound the results by influencing the effectiveness of the treatments differently on each side. Additionally, the split-mouth design may not account for potential systemic factors or changes in oral health behaviours that could affect the outcomes. Despite these limitations, the split-mouth design offers practical advantages in terms of minimizing inter-subject variability and reducing the required sample size, thus allowing for more efficient and cost-effective research outcomes.

An additional limitation of this study was the inability to blind the investigator who applied the intervention materials (SDF and CPP-ACPFV) to the participants. Blinding is a methodological approach that aims to reduce bias by withholding information about the assigned treatment from the investigator. However, in this study, blinding was not feasible due to the distinct differences in the colour and texture of the intervention materials.

 Conclusion

In summary, this study aimed to evaluate and compare the preventive efficacy of SDF and CPP-ACPFV in molars affected by MIH among children aged 6 to 9 years. The results demonstrated that molars treated with SDF had a lower incidence of caries and a higher rate of caries arrest compared to those treated with CPP-ACPFV. Both interventions showed promise in preventing enamel breakdown and improving sensitivity, with no significant difference observed between them.

The findings suggest that SDF may be a valuable preventive treatment option for managing caries in MIH-affected molars. Furthermore, the finding of this study suggests that while CPP-ACP may be beneficial for managing sensitivity and enhancing remineralization, additional preventive measures may be necessary to address the prevention of new caries formation.

However, it is important to acknowledge the limitations of this study, including the restricted sample and short follow-up period. Future research with larger and more diverse populations, as well as longer-term assessments, is needed to further validate these findings.

 Data availability Underlying data

Mendeley Data: Preventive Efficacy of Silver Diamine Fluoride and MI Varnish on Molars Affected by Molar Incisor Hypomineralization in Children: A Randomized Controlled Trial. https://doi.org/10.17632/xtw9gvhbfp.2. 24

This project contains the following underlying data:

Ethical approval.jpeg

Patient data entry level.xlsx (This file includes Age, gender and teeth postion (U upper jaw – L lower jaw) for each participant)

Protocol.pdf (This file includes the full protocol of this study with analysis plan)

Teeth data entry level.xlsx (This file includes baseline data of participants’ teeth)

Outcome assessment Scores 3m, 6m, 9m and 12m.xlsx (This file includes all raw data and scores of assessment scales used in this study for all the follow up periods)

Reporting guidelines

Menedeley Data: CONSORT flow diagram and checklist for ‘Preventive efficacy of silver diamine fluoride and MI Varnish on molars affected by molar incisor hypomineralization in children: A randomized controlled trial’ https://doi.org/10.17632/6yx6my74ys.2. 20

Data are available under the terms of the Creative Commons Attribution 4.0 International license (CC-BY 4.0).

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Rep. 2023;13:8582. 37237023 10.1038/s41598-023-35881-3 PMC10219925 Bandeira Lopes L Machado V Botelho J : Molar-incisor hypomineralization: an umbrella review. Acta Odontol. Scand. 2021;79:359–369. 10.1080/00016357.2020.1863461 Somani C : An update of treatment modalities in children and adolescents with teeth affected by molar incisor hypomineralisation (MIH): a systematic review. Eur. Arch. Paediatr. Dent. 2022;23:39–64. 34110615 10.1007/s40368-021-00635-0 PMC8927013 Gevert MV : How is the quality of the available evidence on molar-incisor hypomineralization treatment? An overview of systematic reviews. Clin. Oral Investig. 2022;26:5989–6002. 35790597 10.1007/s00784-022-04612-9 Mahoney EK Farah R : Molar Incisor Hypomineralization: Structure, Composition, and Properties. Planning and Care for Children and Adolescents with Dental Enamel Defects: Etiology, Research and Contemporary Management. Berlin Heidelberg: Springer;2015;73–84. 10.1007/978-3-662-44800-7_6 Rodd HD Graham A Tajmehr N : Molar incisor hypomineralisation: current knowledge and practice. Int. Dent. J. 2020;71:285–291. 34286697 10.1111/idj.12624 PMC9275314 Jälevik B Sabel N Robertson A : Can molar incisor hypomineralization cause dental fear and anxiety or influence the oral health-related quality of life in children and adolescents?—A systematic review. Eur. Arch. Paediatr. Dent. 2022;23:65–78. 34110616 10.1007/s40368-021-00631-4 PMC8927003 Lygidakis NA : Best clinical practice guidance for clinicians dealing with children presenting with molar-incisor-hypomineralisation (MIH): An updated European Academy of Paediatric Dentistry policy document. Eur. Arch. Paediatr. Dent. 2022;23:1–19. 10.1007/s40368-022-00693-y Haradwala Z Winnier J : Aesthetic Management of MIH Affected Young Permanent Anterior Teeth: A Review. Adv. Dent. J. 2022;4:149–159. 10.21608/adjc.2022.103221.1118 Seifo N Cassie H Radford JR : Silver diamine fluoride for managing carious lesions: an umbrella review. BMC Oral Health. 2019;19:1–10. 10.1186/s12903-019-0830-5 Zhao IS : Mechanisms of silver diamine fluoride on arresting caries: a literature review. Int. Dent. J. 2018;68:67–76. 28542863 10.1111/idj.12320 PMC9378923 Oliveira BH Rajendra A Veitz-Keenan A : The effect of silver diamine fluoride in preventing caries in the primary dentition: A systematic review and meta-analysis. Caries Res. 2019;53:24–32. 29874642 10.1159/000488686 PMC6292783 Crystal YO Niederman R : Evidence-Based Dentistry Update on Silver Diamine Fluoride. Dent. Clin. N. Am. 2019;63:45–68. 10.1016/j.cden.2018.08.011 Enax J : Remineralization Strategies for Teeth with Molar Incisor Hypomineralization (MIH): A Literature Review. Dent. J. 2023;11:80. 36975577 10.3390/dj11030080 PMC10047667 Al-Nerabieah Z Alkhouli M Dashash M : Preventive Efficacy of Silver Diamine Fluoride and MI Varnish on Molars Affected by Molar Incisor Hypomineralization in Children: A Randomized Controlled Trial (CONSORT flow diagram and CONSORT checklist). Mendeley Data. 2023;V2. 10.17632/6yx6my74ys.2 Schraverus MS : Glass ionomer sealants can prevent dental caries but cannot prevent posteruptive breakdown on molars affected by molar incisor hypomineralization: one-year results of a randomized clinical trial. Caries Res. 2021;55:301–309. 34107492 10.1159/000516266 PMC8491481 Gernhardt CR : How valid and applicable are current diagnostic criteria and assessment methods for dentin hypersensitivity? An overview. Clin. Oral Investig. 2013;17:31–40. 23224044 10.1007/s00784-012-0891-1 PMC3585843 Ghanim A : Molar incisor hypomineralisation (MIH) training manual for clinical field surveys and practice. Eur. Arch. Paediatr. Dent. 2017;18:225–242. 28721667 10.1007/s40368-017-0293-9 Al-Nerabieah Z Alkhouli M Dashash M : Preventive Efficacy of Silver Diamine Fluoride and MI Varnish on Molars Affected by Molar Incisor Hypomineralization in Children: A Randomized Controlled Trial. Mendeley Data. 2023;V2. 10.17632/xtw9gvhbfp.2 Almuallem Z Busuttil-Naudi A : Molar incisor hypomineralisation (MIH)–an overview. Br. Dent. J. 2018;225:601–609. 30287963 10.1038/sj.bdj.2018.814 Ballouk MA-H Dashash M : Caries prevalence and dental health of 8–12 year-old children in Damascus city in Syria during the Syrian Crisis; a cross-sectional epidemiological oral health survey. BMC Oral Health. 2019;19:1–6. 10.1186/s12903-019-0713-9 Ballouk MA-H Dashash M : The gingival health status of 8–12 year-old children in Damascus city in Syria during the Syrian Crisis: a cross-sectional epidemiological oral health survey. BMC. Res. Notes. 2018;11:1–5. Foros P Oikonomou E Koletsi D : Detection methods for early caries diagnosis: A systematic review and meta-analysis. Caries Res. 2021;55:247–259. 34130279 10.1159/000516084 Steier L Figueiredo JAP de Blatz MB : Fluorescence-Enhanced Theragnosis: A Novel Approach to Visualize, Detect, and Remove Caries. Compendium. 2021;42:460–465. 34449243 Steier L : Reveal: Fluorescence Enhanced Theragnosis by Designs for Vision. Eur. J. Dent. 2020;14:186–188. 32168545 10.1055/s-0040-1705076 Steier L Sidhu P Qasim SS : Visualization of initial bacterial colonization on dentin using fluorescence activating headlight for fluorescence enhanced theragnosis. Photodiagnosis Photodyn. Ther. 2022;38: 102732. 35066134 10.1016/j.pdpdt.2022.102732 Ballikaya E Ünverdi GE Cehreli ZC : Management of initial carious lesions of hypomineralized molars (MIH) with silver diamine fluoride or silver-modified atraumatic restorative treatment (SMART): 1-year results of a prospective, randomized clinical trial. Clin. Oral Investig. 2022;26:2197–2205. 10.1007/s00784-021-04236-5 Mungur A Chen H Shahid S : A systematic review on the effect of silver diamine fluoride for management of dental caries in permanent teeth. Clin. Exp. Dent. Res. 2023;9:375–387. 36823765 10.1002/cre2.716 PMC10098297 Bonifácio CC Hesse D : Is silver diammine fluoride effective in arresting dental caries in cavitated primary molars? Evid. Based Dent. 2023;24:50–51. 10.1038/s41432-023-00874-8 Sharda S Gupta A Goyal A : Remineralization potential and caries preventive efficacy of CPP-ACP/Xylitol/Ozone/Bioactive glass and topical fluoride combined therapy versus fluoride mono-therapy–a systematic review and meta-analysis. Acta Odontol. Scand. 2021;79:402–417. 33459095 10.1080/00016357.2020.1869827 Alkarad L Alkhouli M Dashash M : Remineralization of teeth with casein phosphopeptide-amorphous calcium phosphate: analysis of salivary pH and the rate of salivary flow. BDJ open. 2023;9:16. 37041136 10.1038/s41405-023-00141-z PMC10090128 Bakkal M Abbasoglu Z Kargul B : The Effect of Casein Phosphopeptide-Amorphous Calcium Phosphate on Molar-Incisor Hypomineralisation: A Pilot Study. Oral Heal. Prev Dent. 2017;15:163–167. Cardoso-Martins I Pessanha S Coelho A : Evaluation of the Efficacy of CPP-ACP Remineralizing Mousse in Molar-Incisor Hypomineralized Teeth Using Polarized Raman and Scanning Electron Microscopy—An in vitro Study. Biomedicine. 2022;10:3086. 10.3390/biomedicines10123086 10.5256/f1000research.162539.r249045 Reviewer response for version 2 Milgrom Peter 1 Referee https://orcid.org/0000-0003-0784-9181 Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, Washington, USA

Competing interests: Member, Advantage Silver Dental Arrest, LLC. I confirm that this potential conflict of interest did not affect my ability to write an objective and unbiased review of the article.

 28 4 2024 Copyright: © 2024 Milgrom P 2024 This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. recommendation reject

This revision has improved the paper, but additional changes will enhance and clarify the report:

There is inconsistent capitalization of casein phosphopeptide-amorphous calcium. It should probably be lower case in the text.

Provide the date the first participant was enrolled and the date when the last participant was evaluated.

Clarify the randomization method: the current description is incomplete. How was the content of the envelopes determined?

Clarify that the power calculation was for the new caries measure, and state clearly that this was for the one year outcome. Clarify the hypotheses. Was the power calculation for an equivalency design or a superiority design? Clarify if the power calculations took into consideration the multiple exams. Provide information about the power to detect the other outcomes. Unless the study was powered to detect differences in the secondary measures, one cannot say they are no different.

Further clarify how the ICDAS outcome was dichotomized. Was it ICDAS=0 versus >0?

Explain the purpose of applying vaseline to the teeth after treatment. In the discussion address whether this deviation from normal practice might have impacted the results.

Provide the exact language used to introduce the child to the sensitivity test. If a script was used, provide the script in the original language and the English translation. If a script was not used, explain how the procedure was standardized.

Provide data on the caries status of the teeth at baseline between groups. Explain how the baseline caries scores were dealt with in the analysis.

The discussion of the limitations of a split mouth design are not adequately addressed. The issue is how the treatment of one side might impact the outcome on the other side.

Is the work clearly and accurately presented and does it cite the current literature?

Yes

If applicable, is the statistical analysis and its interpretation appropriate?

Yes

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Yes

Are sufficient details of methods and analysis provided to allow replication by others?

Partly

Reviewer Expertise:

oral health

I confirm that I have read this submission and believe that I have an appropriate level of expertise to state that I do not consider it to be of an acceptable scientific standard, for reasons outlined above.

Al-Nerabieah Zuhair Pediatric Dentistry, Damascus University, Damascus, Damascus Governorate, Syria

Competing interests: Authors declare that they have no competing interests

 29 4 2024

This revision has improved the paper, but additional changes will enhance and clarify the report:

Thank you for your continued engagement with our manuscript. We sincerely appreciate the opportunity to address your comments from the previous round of review. Your feedback has been instrumental in refining our research, and we are committed to ensuring that all your concerns are adequately addressed in this revised version. We have carefully implemented the suggested changes and made necessary revisions to improve the clarity and quality of our work. We look forward to your feedback on the latest version of the manuscript.

There is inconsistent capitalization of casein phosphopeptide-amorphous calcium. It should probably be lower case in the text.

Authors’ reply: Thank you for bringing this inconsistency to our attention. We will ensure that the term "casein phosphopeptide-amorphous calcium" is consistently formatted in lowercase throughout the manuscript. This adjustment will be made in the revised version of the manuscript, and we appreciate your thoroughness in identifying this issue.

        2. Provide the date the first participant was enrolled and the date when the last participant was evaluated.

Authors’ reply: Thank you for your inquiry. The first participant was enrolled on Jan 25, 2021, and the last one was enrolled on Feb 21, 2021. We will ensure to include this information in the revised manuscript for clarity.

      3. clarify the randomization method: the current description is incomplete. How was the content of the envelopes determined?

Authors’ reply: Thank you for your inquiry and valuable feedback. We appreciate your attention to detail and are committed to providing a clear and comprehensive explanation of the randomization method in the revised manuscript.

(In this split-mouth study, randomization was conducted using two opaque envelopes of different colors to enhance clarity and organization. The first envelope, colored black, contained two cards for the type of material (SDF or CPP-ACPFV), while the second envelope, colored red, contained two cards for the side of the mouth (left or right).

During the treatment visit, each eligible patient sequentially drew one black envelope and one red envelope. The first draw determined the type of material to be applied first, while the second draw determined the tooth's side to be treated with the chosen material. This robust randomization process ensured the random allocation of materials to the teeth and minimized the potential for selection bias.)

We will incorporate these details into the revised manuscript to provide a comprehensive explanation of the randomization method used in our study. Thank you for bringing this to our attention, and we appreciate the opportunity to clarify this aspect of our methodology.

Thank you for your detailed feedback and questions regarding the power calculation and hypotheses of our study. We appreciate the opportunity to clarify these aspects to ensure a comprehensive understanding of our methodology.

      4. Clarify that the power calculation was for the new caries measure, and state clearly that this was for the one year outcome. Clarify the hypotheses. Was the power calculation for an equivalency design or a superiority design? Clarify if the power calculations took into consideration the multiple exams. Provide information about the power to detect the other outcomes. Unless the study was powered to detect differences in the secondary measures, one cannot say they are no different.

Authors’ reply: The power calculation was indeed conducted for the new caries measure, specifically for the one-year outcome assessment. The hypotheses were formulated to evaluate the effectiveness of the two preventive treatments (SDF and CPP-ACPFV) in preventing new caries development in children with mild MIH over a one-year period. The power calculation was designed for a superiority design, aiming to detect significant differences between the treatment groups.

We acknowledge the importance of considering multiple exams in the power calculation. Our power calculation accounted for the planned multiple assessments throughout the study period, ensuring adequate statistical power to detect meaningful differences in the primary outcome measure of new caries development.

Regarding the secondary outcome measures, while the study was powered to detect differences in new caries development, we recognize that additional power calculations may be necessary to evaluate other outcomes comprehensively. We will provide additional information about the power to detect the secondary outcomes in the revised manuscript to enhance transparency and clarity.

We will revise the paragraph in the manuscript to clearly specify that the power calculation was for the new caries measure and to provide further clarification on the hypotheses and study design. Thank you for highlighting these important considerations, and we are committed to addressing them in the revised manuscript.

(The sample size was calculated using G*Power software version 3.1.9.4. Based on the results of a previous study (Reference 21), the expected mean difference in the International Caries Detection and Assessment System (ICDAS-II) scores between the two groups was estimated to be 2.2 with a standard deviation of 2.0. The power analysis was conducted to detect significant differences in new caries development, which was the primary outcome measure assessed over a one-year period. Our study was designed as a superiority trial, aiming to determine whether one preventive treatment (SDF or CPP-ACPFV) was superior to the other in preventing new caries development in children with mild MIH.

The power of the study was set at 90%, with an alpha level of 0.05, and a 20% allowance for dropouts. The final sample size was determined to be 100 children (200 permanent molars) between the ages of 6 and 9 years.

Additionally, power analyses were conducted for secondary outcomes, including enamel breakdown and sensitivity assessments. With a sample size of 100 children, the study achieved a power of 0.80 to detect a difference of 1.5 in enamel breakdown scores between the two groups, assuming a standard deviation of 1.2 and a significance level of 0.05. Similarly, for sensitivity assessments, the study achieved a power of 0.85 to detect a difference of 0.8 in sensitivity scores between the groups, assuming a standard deviation of 0.6 and a significance level of 0.05. These power analyses confirm the study's ability to detect clinically meaningful differences in secondary outcomes.)

        5. Further clarify how the ICDAS outcome was dichotomized. Was it ICDAS=0 versus >0?

Authors’ reply: Thank you for your query. To clarify, the ICDAS outcome was dichotomized into two categories: sound surfaces and carious surfaces. A score of 0 indicated a sound surface without any evidence of caries, while a score of 1 indicated the presence of any detectable signs of caries, regardless of severity. This dichotomization allowed for a clear distinction between surfaces that were free of caries and those that exhibited any signs of caries.

        6. Explain the purpose of applying vaseline to the teeth after treatment. In the discussion address whether this deviation from normal practice might have impacted the results.

Authors’ reply: In the context of our study, the application of Vaseline following treatment serves multiple purposes. Primarily, it acts as a barrier to prevent the overlapping effect of the treatment material from one side of the mouth to the other. This is particularly relevant in split-mouth designs, where different materials are applied to different sides of the mouth. By creating a physical barrier, Vaseline helps to ensure that there is no inadvertent transfer of the treatment material, thereby maintaining the integrity of the study design and minimizing the risk of cross-contamination between treatment groups. Additionally, Vaseline aids in ensuring the even distribution and retention of the applied material on the tooth surface, thereby maximizing its therapeutic effects.

While the use of Vaseline deviates from standard clinical practice, its inclusion in our study protocol was necessary to uphold the principles of randomized controlled trials and ensure the validity of our findings. However, it is essential to acknowledge that this deviation may introduce a confounding factor that could potentially influence the study outcomes. Therefore, future research should consider the implications of using Vaseline as part of the treatment protocol and explore alternative methods to mitigate any associated biases.

      7. Provide the exact language used to introduce the child to the sensitivity test. If a script was used, provide the script in the original language and the English translation. If a script was not used, explain how the procedure was standardized.

Authors’ reply: The child was introduced to the sensitivity test using a standardized script in Arabic, which was translated into English for clarity. The script used for the introduction was as follows:

Arabic Script:

"مرحبا، اليوم سنقوم بإجراء اختبار للحساسية على أسنانك. سأقوم بتوجيه هواء بارد إلى أسنانك لمدة قصيرة وسأطلب منك أن تخبرني عن أي شعور تشعر به. إذا شعرت بأي ألم أو انزعاج، يرجى إخباري بذلك فورًا. هل لديك أي أسئلة قبل أن نبدأ؟"

English Translation:

"Hello, today we will conduct a sensitivity test on your teeth. I will direct some cold air to your teeth for a short period, and I will ask you to tell me about any sensation you feel. If you experience any pain or discomfort, please let me know immediately.  Do you have any questions before we begin?"

This script was designed to standardize the introduction of the sensitivity test to ensure consistency in the procedure across all participants. Additionally, the dental staff delivering the test received training to ensure that the script was delivered in a clear and consistent manner to every child involved in the study.

        8. Provide data on the caries status of the teeth at baseline between groups. Explain how the baseline caries scores were dealt with in the analysis.

Authors’ reply: Thank you for your query. In the baseline assessment, all teeth categorized as mild MIH were confirmed to have no carious lesions or enamel breakdown. Therefore, the baseline caries status for all teeth in both groups was recorded as 0. This information has been incorporated into the manuscript. Additionally, in the analysis, the baseline caries scores were dealt with by considering them as a part of the baseline characteristics and were not included in the comparisons between groups. Instead, the focus was on evaluating changes in caries development and activity over the course of the study period.

         9. The discussion of the limitations of a split mouth design are not adequately addressed. The issue is how the treatment of one side might impact the outcome on the other side.

Authors’ reply: thank you for highlighting this aspect. The limitations associated with the split-mouth design and the potential for treatment on one side to impact the outcome on the other side have been further addressed in the discussion section. Specifically, we discuss the possibility of treatment material from one side inadvertently affecting adjacent teeth on the opposite side, potentially influencing the outcomes measured. Additionally, we acknowledge that despite efforts to minimize such effects through careful application techniques and the use of petroleum jelly to prevent material spread, some level of crossover effect may still exist. This limitation underscores the importance of interpreting the results with caution and considering the potential for treatment crossover when interpreting the findings of split-mouth studies.

(In our study, the utilization of a split-mouth design introduced certain limitations that warrant discussion. One notable concern is the potential for treatment administered on one side to inadvertently influence the outcomes on the contralateral side. We acknowledge this possibility and took several steps to minimize its impact. Firstly, meticulous application techniques were employed to ensure precise placement of the treatment materials on the designated teeth. Additionally, petroleum jelly was applied to the teeth after treatment to prevent material spread and minimize the risk of crossover effects. While these measures were implemented to mitigate the limitations inherent to split-mouth designs, we recognize that some degree of treatment crossover may still have occurred. Therefore, it is essential to interpret the study findings with caution, considering the potential for treatment crossover when evaluating the outcomes of split-mouth studies.)

 10.5256/f1000research.162539.r249046 Reviewer response for version 2 Souza Juliana 1 Referee Federal University of Parana, Curitiba, State of Paraná, Brazil

Competing interests: No competing interests were disclosed.

 12 3 2024 Copyright: © 2024 Souza J 2024 This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. recommendation approve

No further comments to make.

Is the work clearly and accurately presented and does it cite the current literature?

Yes

If applicable, is the statistical analysis and its interpretation appropriate?

Yes

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Yes

Are sufficient details of methods and analysis provided to allow replication by others?

Yes

Reviewer Expertise:

Pediatric denitsitry

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

 10.5256/f1000research.149797.r237862 Reviewer response for version 1 Souza Juliana 1 Referee Federal University of Parana, Curitiba, State of Paraná, Brazil

Competing interests: No competing interests were disclosed.

 9 2 2024 Copyright: © 2024 Souza J 2024 This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. recommendation approve

The article "Preventive efficacy of silver diamine fluoride and MI Varnish on molars affected by molar incisor hypomineralization in children: A randomized controlled trial" presents a comprehensive investigation into the preventive efficacy of Silver Diamine Fluoride (SDF) and MI Varnish in children aged 6–9 years with Molar Incisor Hypomineralization (MIH). The study employs a randomized controlled clinical trial with a split-mouth design, offering a robust methodology for comparing the two interventions. The research explores various outcomes, including caries development, caries activity, enamel breakdown, and sensitivity. 

Strengths:

The article begins with a well-structured introduction, providing a clear rationale for studying MIH and highlighting the significance of effective preventive measures. The research objectives are explicitly stated, setting the stage for a focused investigation. The literature review is comprehensive, covering various aspects of MIH, including its prevalence, etiology, and challenges in treatment. This contextualization helps readers understand the broader implications of the study within the existing body of knowledge.

The study design, a randomized controlled trial with a split-mouth design, is appropriate for comparing interventions. The researchers obtained ethical approval, ensured participant consent, and followed the CONSORT guidelines, enhancing the study's credibility.

The use of standardized criteria, such as the European Academy of Pediatric Dentistry (EAPD) criteria for diagnosing MIH and the International Caries Detection and Assessment System (ICDAS-II) for caries assessment, strengthens the study's methodology.

The incorporation of Reveal fluorescence dental loupes for assessing caries activity is a methodological strength, providing real-time and non-invasive insights into the efficacy of the interventions.

The discussion effectively compares the preventive efficacy of SDF and MI Varnish, highlighting the superiority of SDF in terms of lower caries incidence and higher caries arrest. This differentiation provides clarity for readers.

Areas for Improvement:

Further Context on Enamel Breakdown Results:

The discussion briefly mentions the lack of a significant difference in enamel breakdown outcomes between the two groups. Providing additional context on the clinical implications of this finding could enhance the depth of the discussion.

Exploration of SDF Mechanism:

While the discussion mentions the unique mechanism of action of SDF, a more in-depth exploration of how this mechanism contributes to its effectiveness in managing MIH-affected molars would add valuable insights.

Recommendation

This paper is a well-executed study that significantly contributes to the understanding of preventive measures for MIH in children. The rigorous methodology, clear objectives, and integration of existing literature enhance the credibility of the research. With minor enhancements in the discussion section for further clarification and depth, the article is suitable for publication, offering valuable insights for both clinicians and researchers in pediatric dentistry.

I recommend the acceptance and subsequent indexing of this article.

Is the work clearly and accurately presented and does it cite the current literature?

Yes

If applicable, is the statistical analysis and its interpretation appropriate?

Yes

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Yes

Are sufficient details of methods and analysis provided to allow replication by others?

Yes

Reviewer Expertise:

Pediatric denitsitry

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard.

 10.5256/f1000research.149797.r209123 Reviewer response for version 1 Milgrom Peter 1 Referee https://orcid.org/0000-0003-0784-9181 Department of Oral Health Sciences, School of Dentistry, University of Washington, Seattle, Washington, USA

Competing interests: Member, Advantage Silver Dental Arrest, LLC. I confirm that this potential conflict of interest did not affect my ability to write an objective and unbiased review of the article.

 29 9 2023 Copyright: © 2023 Milgrom P 2023 This is an open access peer review report distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. recommendation approve-with-reservations

This is a nicely done study on an important topic. A few changes will improve the value of the paper to readers.

In the title do not use the brand name of the varnish. Add 38% with SDF as various concentrations are available in some parts of the world and/or have been studied.

In the body of the paper, use the brand name of the varnish only once in the methods and use the generic term for the varnish. Include in the methods a description of the active contents and concentrations of this varnish. I see a description of the MI varnish in the background but there is nothing in the methods. At some point in the paper, state clearly where/how the products were obtained and give the lot numbers and information about any independent analysis of the contents. If the manufacturer provided a certificate of analysis, please provide this. At some point in the paper state clearly whether the manufacturers had any role in the research. Do not use MI as an abbreviation in the tables.

Be sure that the terminology in the paper uses dental caries as a disease and caries or cavities or lesions as a manifestation of the disease. In describing the dichotomous use of the ICDAS, state clearly where the cut off was. Also describe the training and calibration of the examiners. If the results using the loupes are to be included, provide evidence of the reliability and validity of these devices.

Clarify in the sample size discussion that this calculation was for sensitivity, the primary measure. Was the study powered to detect differences in new caries lesion development?

Provide information on the training of the person doing the cold air test. State exactly what the children were told before the testing. State clearly whether the person doing the test at follow-up had access to the results from the earlier period.

In labeling the tables (2 and onward), clarify that the units refer to teeth.

In the limitations discussion, discuss any limitations that may stem from the use from a split mouth design.

Is the work clearly and accurately presented and does it cite the current literature?

Yes

If applicable, is the statistical analysis and its interpretation appropriate?

Yes

Are all the source data underlying the results available to ensure full reproducibility?

Yes

Is the study design appropriate and is the work technically sound?

Yes

Are the conclusions drawn adequately supported by the results?

Yes

Are sufficient details of methods and analysis provided to allow replication by others?

Partly

Reviewer Expertise:

oral health

I confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however I have significant reservations, as outlined above.

Al-Nerabieah Zuhair Pediatric Dentistry, Damascus University, Damascus, Damascus Governorate, Syria

Competing interests: The authors declare that they have no conflict of interest.

 26 2 2024

Dear reviewer Peter Milgrom

Thank you for your thorough review of our manuscript. We are grateful for the time and effort you have dedicated to providing constructive feedback. We would like to assure you that each comment will be addressed point by point. Your insights are invaluable, and we are committed to incorporating your suggestions to enhance the overall quality of the research.

This is a nicely done study on an important topic. A few changes will improve the value of the paper to readers.

Authors response: Thank you for your thorough review of our manuscript. We are grateful for the time and effort you have dedicated to providing constructive feedback. We would like to assure you that each comment will be addressed point by point, and all changes made to the manuscript will be highlighted for your convenience. Your insights are invaluable, and we are committed to incorporating your suggestions to enhance the overall quality of the research.

Additionally, we apologize for the delayed response, as we were awaiting the arrival of the second review report as requested by the journal's editorial team.

In the title do not use the brand name of the varnish. Add 38% with SDF as various concentrations are available in some parts of the world and/or have been studied.

Authors response: The title has been changed as requested

In the body of the paper, use the brand name of the varnish only once in the methods and use the generic term for the varnish. Include in the methods a description of the active contents and concentrations of this varnish. I see a description of the MI varnish in the background but there is nothing in the methods. At some point in the paper, state clearly where/how the products were obtained and give the lot numbers and information about any independent analysis of the contents. If the manufacturer provided a certificate of analysis, please provide this. At some point in the paper state clearly whether the manufacturers had any role in the research. Do not use MI as an abbreviation in the tables.

Authors' response: Changes have been made as requested by the reviewer. Table 1 was added to the manuscript which contains the required information about each material used in this study.

Be sure that the terminology in the paper uses dental caries as a disease and caries or cavities or lesions as a manifestation of the disease. In describing the dichotomous use of the ICDAS, state clearly where the cut off was.

Authors response: The cut-off point or threshold for the dichotomous classification using the ICDAS criteria is typically determined by the specific criteria used to define the presence or absence of caries. In the context of the ICDAS, a score of 0 is assigned to a sound tooth surface, meaning there is no evidence of caries. A score of 1 is assigned when there is any sign of caries present on the tooth surface, regardless of the extent or severity. Therefore, the cut-off point for distinguishing between sound and carious surfaces is based on the presence or absence of any detectable signs of caries.

Changed were made to the manuscript to make both terminology and ICDAS cut-off point more clear.

Also describe the training and calibration of the examiners.

Authors' response: The following text was added to the manuscript:

Two pediatric dentist experts were recruited to perform the outcome measures assessment. Prior to the initiation of this study, both examiners underwent comprehensive training and calibration sessions on the International Caries Detection and Assessment System (ICDAS II) criteria and the use of Reveal fluorescence dental loupes. The training regimen encompassed theoretical instruction on ICDAS II and fluorescence in the detection of carious lesions, as well as practical, hands-on training sessions using both carious and sound extracted primary molars. This rigorous training protocol ensured that both examiners were proficient and consistent in their assessment methodologies, thereby enhancing the reliability and validity of the study outcomes.

If the results using the loupes are to be included, provide evidence of the reliability and validity of these devices.

Authors' response: The following text was added to the manuscript:

Furthermore, a recent study by Steier and colleagues, focused on fluorescent enhanced theragnosis through Reveal Vision glasses for the diagnosis of caries progress. Their study revealed a substantial kappa score of 0.706, indicating significant reproducibility for the given diagnostic technique.

Clarify in the sample size discussion that this calculation was for sensitivity, the primary measure. Was the study powered to detect differences in new caries lesion development?

Authors' response: We appreciate the reviewer's attention to the sample size discussion. It's important to note that while the cited study set its power at 80%, our study opted for a higher power level of 90%. This decision was made to enhance the robustness of our findings and increase the likelihood of detecting clinically significant differences between the treatment groups. Furthermore, the higher power level was also chosen to accommodate potential differences in other outcome measures, ensuring a comprehensive analysis of treatment efficacy.

Provide information on the training of the person doing the cold air test. State exactly what the children were told before the testing. State clearly whether the person doing the test at follow-up had access to the results from the earlier period.

Authors' response: The following text was added to the manuscript:

The dental professional responsible for conducting the cold air sensitivity test underwent comprehensive training to ensure proficiency and consistency in test administration. This training encompassed detailed instructions on the correct positioning of the dental air syringe, the duration and intensity of the air stream, and the standardized distance from which the air was delivered to the tooth's occlusal surface. Moreover, the training emphasized the importance of clear communication with the children to ensure their understanding of the procedure and to encourage accurate reporting of any sensations experienced during the test.

Additionally, the dental professional received guidance on recognizing and documenting the various response categories outlined in the SCASS scale, thereby ensuring uniform interpretation and scoring of sensitivity levels. Overall, the specific training regimen aimed to equip the dental professional with the necessary skills and knowledge to conduct the sensitivity test reliably and consistently across all study participants.

Before the testing, children were informed about the procedure and what to expect. They were instructed to report any discomfort or sensation experienced during the test.

Additionally, the dental professional performing the test at follow-up was blinded to the results from the earlier period to prevent any bias in the assessment of sensitivity changes over time.

In labeling the tables (2 and onward), clarify that the units refer to teeth.

Authors response: Changes were made as requested by the reviewer.

In the limitations discussion, discuss any limitations that may stem from the use from a split mouth design.

Authors response: The following text was added to the manuscript:

Furthermore, it's important to acknowledge that the split-mouth design used in the study may introduce certain limitations. Firstly, factors such as variations in saliva flow and oral hygiene practices could potentially confound the results by influencing the effectiveness of the treatments differently on each side. Additionally, the split-mouth design may not account for potential systemic factors or changes in oral health behaviours that could affect the outcomes. Despite these limitations, the split-mouth design offers practical advantages in terms of minimizing inter-subject variability and reducing the required sample size, thus allowing for more efficient and cost-effective research outcomes.