Knowledge, Attitudes, and Practices towards Silver Diamine Fluoride among Dentists in Vietnam.

Silver diamine fluoride (SDF) is a topical solution used for managing dental caries. The mixed-methods study consists of a quantitative study (questionnaire survey) and a qualitative study (in-depth interview) to explore the knowledge, attitudes, and practices towards SDF among dentists in Vietnam. A descriptive approach and a thematic approach were performed to analyze data, respectively. The questionnaire survey invited 436 licensed dentists registered for the national annual dental meeting and 226 dentists participated (response rate: 52%). Among them, 174 (77%, 174/226) dentists knew SDF, and 69 (40%, 69/174) dentists used SDF for caries management. Most of them considered SDF therapy as non-invasive (84%, 146/174) and simple (80%, 140/174). However, most of them expressed concern that SDF could discolor the tooth (74%, 128/174). Their most preferred teeth for SDF therapy were primary posterior teeth (92%, 160/174). The in-depth interview consulted 16 dentists to reach data saturation. They learned about SDF from outside curriculum resources as an effective anti-caries agent. They understood the advantages (simple, non-invasive, timesaving) and disadvantages (tooth discoloring, ammonia odor) of SDF. They used SDF to arrest caries in uncooperative children in the clinic and people living in rural areas in outreach services. Most dentists in Vietnam are supportive of SDF therapy, and they know its advantages and disadvantages for caries management. The results addressed the aim of the study to investigate Vietnamese dentists' perspectives towards SDF.

Early childhood caries and its associated factors among 5-years-old Myanmar children.

Introduction: Children's oral health plays a crucial role in their overall well-being and there is a significant gap in our understanding of early childhood caries (ECC) in Myanmar. This study aims to bridge this knowledge deficit by investigating the prevalence, causes, and potential interventions for ECC in the Myanmar population, providing crucial insights for future dental health policies and practices. Methods: Generally healthy 5-year-old kindergarten children from 7 districts in city were recruited. ECC was assessed through clinical examinations using decayed, missed, filled teeth (dmft). Additionally, demographic data of the children and their caregivers, along with information about the children's oral health-related behaviors, were gathered using a structured questionnaire. Results: Out of the 496 children, the overall prevalence of dental caries was 87.1% (mean dmft score: 5.57, SD: 4.6). Caries experience was categorized as severe (45.8%) and non-severe (41.3%). Decayed teeth constituted the major component of the dmft index (97.8%). Multiple logistic regression analysis revealed two significant factors associated with ECC prevalence: late toothbrushing initiation (OR: 2.54, p = 0.001) and dental visit experience (OR: 2.46, p = 0.010). Discussion: The study highlights the alarming ECC prevalence in 5-year-old children in Mandalay, Myanmar, with mostly untreated decayed teeth. The findings emphasize early preventive oral health measures for young children to reduce ECC burden in Myanmar.

Self-reported oral health-related quality of life and caries experiences of 5-year-old children in Mandalay, Myanmar.

BACKGROUND: This study aimed to examine the impact of dental caries and other potential socio-demographic factors on the oral health-related quality of life (OHRQoL) of preschool children from Myanmar. This was done using the Scale of Oral Health Outcomes for 5-year-old children (SOHO-5) as reported by both the children and their parents. METHODS: A structured questionnaire was conducted to collect demographic information about the children and their caregivers, as well as socioeconomic data. The OHRQoL was assessed by interviewing the children and their parents using the Myanmar versions of SOHO-5c and SOHO-5p, respectively. Caries experience was assessed by two calibrated examiners and recorded using the dmft index. The Poisson regression model was adopted to investigate the association between OHRQoL and dental caries including socioeconomic factors. RESULTS: A total of 454 pairs participated in the study. Among them, 64% of children and 70% of parents reported a negative impact on OHRQoL (with SOHO-5c and SOHO-5p scores exceeding 0). The mean score (SD) of the child self-report and parental version of the SOHO-5 was 1.86 (2.27) and 2.65 (3.13), respectively. Difficulties in eating and sleeping were the most commonly reported by both children and parents. The overall prevalence of dental caries was 87% (mean dmft score:5.59, SD:4.65). The final multivariate-adjusted model revealed that children with higher caries experiences were more likely to have lower OHRQoL for both child self-report (RR 4.38, 95% CI 3.16-6.14, p < 0.001) and parental report (RR 6.07, 95% CI 4.38-8.41, p < 0.001), respectively. A lower family income had a negative impact on the children's OHRQoL in child self-report (RR 1.59, 95% CI 1.26-2.04, p < 0.001) and parental report (RR 1.46, 95% CI 1.19-1.78, p < 0.001). CONCLUSION: Two-thirds of the study children and their parents perceived the negative impact on children's OHRQoL. Higher caries experience and lower family income were associated with poorer OHRQoL of 5-year-old Myanmar children.

Tools Evaluating Child Oral Health-Related Quality of Life.

OBJECTIVES: This study aimed to systemically review the tools developed for evaluating oral health-related quality of life (OHRQoL) in preschool children. METHODS: Two reviewers systematically searched English-language publications within PubMed, Embase, Scopus, and Web of Science. They screened the titles and abstracts and retrieved the full texts of the selected publications. Studies which developed, validated, or culturally adapted an OHRQoL tool used in preschool children were included. They recorded information regarding tool characteristics, item configuration, discriminative validation, the aim of assessment, and the target group. RESULTS: The study included 59 publications and identified 12 tools for assessing OHRQoL in preschool children. Seven tools were tailored for preschool ages. Most of the scales were generic oral health measures. Dental caries was the most commonly used oral condition for assessing a tool's discriminative validity. Eight tools required parental proxy reports. Three tools were both child-administrated and parent-administrated. One tool was designed to be answered solely by children. Ten tools assessed the oral health-related impact on children, including oral condition-related, functioning, environmental, and emotional/social domains. Four tools included items regarding the impact on both children and family. CONCLUSIONS: This review identified 12 tools developed for evaluating OHRQoL in preschool children, 7 of which were tailored for preschool age. The 12 tools were validated but incomprehensive due to the subjective and multidimensional nature of the OHRQoL concept. Researchers can choose a suitable tool for their studies by understanding the basic characteristics and item setting of the tools. Researchers can have an overview of the tools developed for evaluating OHRQoL in preschool children. They can use the findings from this review to choose a suitable tool for their studies regarding the OHRQoL in preschool children.

Antibiofilm and mechanical properties of silver nanowire-modified glass ionomer cement.

BACKGROUND: Glass ionomer cement (GIC) is a commonly used restorative material in dentistry, but GIC does not have significant antibiofilm effects and its mechanical strength is limited. OBJECTIVE: To investigate the antibiofilm and mechanical properties of a newly developed silver nanowire (AgNW) modified GIC. METHODS: GICs were modified with different nanosilver formulations including 0.05%wt AgNW, 0.5%wt AgNW, 0.05%wt silver nanoparticle (AgNP) and 0.5%wt AgNP. Biofilms of Streptococcus mutans were cultured for 72 h on GIC specimens. Scanning electron microscopy (SEM) was conducted to observe the accumulation and morphology of Streptococcus mutans on the material surfaces. Another set of biofilm/specimens was treated with SYTO-9 and the biofilm development was evaluated by quantifying the visible stain with an inverted fluorescence microscope. The compressive strength of the specimens was assessed according to ISO 9917-1:2007. The colour of GICs was compared using the VITA Easyshade system. RESULTS: SEM images showed that fewer biofilms were accumulated on nanosilver-modified GICs. The Streptococcus mutans quantity was significantly lower in all nanosilver-modified groups compared to conventional GIC (p<0.0001). GIC modified with 0.5% AgNP showed slightly lower compressive strength than the negative control (58.3 ± 12.9 MPa vs 78.3 ± 13.8 MPa); but there is no significant difference between all study groups. The colour change between AgNW-modified GIC and conventional GIC was significantly lower than that between AgNP-modified GIC and conventional GIC. CONCLUSION: AgNW-modified GIC showed superior antibiofilm effect and comparable compressive strength to conventional GIC. In addition, the complement of AgNW would not influence the colour stability of GIC as much as AgNP. CLINICAL SIGNIFICANCE: This study developed a novel AgNW-modified GIC material. It showed good antibiofilm and mechanical properties and would not influence the colour stability of GIC. The AgNW-modified GIC has a large potential for clinical use and biomedical application.

Cross-cultural adaptation and psychometric properties of the Myanmar version of the scale of oral health outcomes for 5-year-old children.

OBJECTIVE: The aim of this study was to cross-culturally adapt the child's self-report and parental report of the scale of oral health outcomes for 5-year-old children (SOHO-5) for use in Myanmar (Burmese-speaking) population and to assess the reliability and validity of the Myanmar version. MATERIALS AND METHODS: The forward-backward translation method was used to develop the Myanmar SOHO-5 version and the final questionnaires were tested on 173 five years old children and their parents for reliability and validity. A single dentist examined the caries experience of the children (Kappa:0.90). The structural validity was assessed through confirmatory factor analysis. The internal consistency and test-retest reliability (1-2 weeks) were evaluated using Cronbach's alpha and intraclass correlation coefficient (ICC), respectively. The association between SOHO-5 scores and additional global rating questions for child oral health status (convergent validity) and the differences between the total SOHO-5 score of children with caries and children without caries (discriminant validity) were investigated. RESULTS: A confirmatory factor analysis indicated a good fit for the one-factor structure of the SOHO-5. Cronbach's alpha coefficient values for internal consistency were 0.82 for the children's report and 0.79 for the parental report. The ICCs were 0.90 and 0.89 for the total scores of the children and parental versions in the test-retest reliability analysis. The total SOHO-5 scores for both reports were significantly associated with the global rating questions except for the 'impact on children's general health' question in the parental report. Furthermore, the Myanmar version discriminated between the children with and without caries experiences (p < 0.001). CONCLUSION: This study provided evidence that both children and parental reports of the Myanmar SOHO-5 version have good reliability and validity to assess the OHRQoL of 5-year-old children in a Burmese-speaking population.

Caries Prevention Using Silver Diamine Fluoride: A 12-Month Clinical Trial.

OBJECTIVE: This clinical trial aimed to compare the caries-preventive effect of annual application of 38% silver diamine fluoride solution (SDF) with 5% sodium fluoride varnish (FV) to the anterior primary teeth of children. The hypothesis was that SDF was superior to FV at 1 year. Secondary objectives were to determine the child's cooperation and the parent's satisfaction and assess adverse effects. METHOD: We recruited 688 3- to 4-year-old children and randomly allocated them to receive SDF or FV (positive control) on their 6 upper anterior teeth. Tooth-surface status was recorded using the decayed, missing, and filled surfaces index. A trained observer rated the child's cooperation as "totally cooperative" or "not totally cooperative." We used a questionnaire to determine the parent's satisfaction as "satisfied," "neutral," or "dissatisfied." Adverse effects (yes/no) were evaluated 1 day and about 1 year after treatment. RESULTS: Of the children, 434 (SDF, n = 209; FV, n = 225) completed the trial. The mean new decayed tooth surfaces developed for SDF and FV groups were 0.4 ± 1.5 and 0.4 ± 1.3, respectively (P = .65). Child's cooperation for SDF and FV therapy was 71% (244/344) and 70% (241/344), respectively (P = .89). Parent's satisfaction for SDF and FV therapy was 71% (148/209) and 69% (155/225), respectively (P = .29). Adverse effects were found neither at 1 day nor at about 1 year after treatment for either treatment arm. CONCLUSIONS: SDF is not superior to FV for caries prevention in primary upper anterior teeth at 1-year follow-up. Child's cooperation and parent's satisfaction were similarly high with SDF and FV therapy at 1-year follow-up. Neither short-term nor long-term adverse effects were observed. This study is registered at ClinicalTrials.gov (NCT04399369).

Psychometric properties of the Thai version of the Scale of Oral Health Outcomes for 5-year-old children.

BACKGROUND: As caries prevalence in Thai preschool children is very high and its consequences have scarcely been evaluated, the Scale of Oral Health Outcomes for 5-year-old children (SOHO-5) is considered as an appropriate tool to measure the children's oral health-related quality of life (OHRQoL). AIM: To translate the SOHO-5 into Thai (Th-SOHO-5) and assess its psychometric characteristics. DESIGN: The cross-cultural adaptation of the SOHO-5 into Thai comprised forward-backward translation by experts and face validation by 20 child-parent dyads. To evaluate psychometric properties of the final version, a cross-sectional study was conducted on 306 child-parent pairs using an interview mode for children and a self-administered mode for parents. A trained investigator examined children's caries status. RESULTS: The Th-SOHO-5 showed satisfactory psychometric characteristics. Cronbach's alpha values were above 0.8 for both child and proxy reports. Overall intraclass correlation coefficients were > 0.9. Factor analysis supported a single-factor structure model of the Th-SOHO-5 and showed an excellent fit. Th-SOHO-5 scores were correlated with all global rating scales of oral health and well-being. Children with higher caries experience or caries with pulpal involvement demonstrated significantly higher Th-SOHO-5 scores. CONCLUSION: The Th-SOHO-5 possessed good reliability and validity. It can be used to evaluate the OHRQoL of preschool children in Thailand.

Quality of the adaptation procedures and psychometric properties of the scale of oral health outcomes for 5-year-old children (SOHO-5): a systematic review.

PURPOSE: The aim of this study was to assess the quality of the cross-cultural adaptations and psychometric properties of the Scale of Oral Health Outcomes for 5-year-old children (SOHO-5). METHODS: A systematic search was performed in three databases, PubMed, SCOPUS, and Dentistry and Oral Science Source (EBSCO). Studies relating to the cross-cultural adaptation and psychometric properties of SOHO-5 were included. The quality of cross-cultural adaptation was assessed in five aspects including translation, synthesis, back-translation, expert committee review, and pretesting. The Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist was used to assess the psychometric properties in seven domains including responsiveness, internal consistency, reliability, measurement error, and structural, construct, and cross-cultural validity. RESULTS: The search identified 162 papers for screening; from these, 107 articles and 9 systematic reviews were excluded. 21 full papers were retrieved and 6 studies that met the inclusion criteria were included. Out of six, two reported all five aspects of cross-cultural adaptation procedures. Regarding the psychometric properties, none of the studies evaluated all aspects of psychometric properties. Almost all of the studies reported internal consistency (Cronbach's alpha ranging from 0.71 to 0.90), test-retest reliability (Intraclass Correlation Coefficient 0.46-0.98), and construct validity. None reported the cross-cultural validity and responsiveness of the measures. CONCLUSION: While these studies provided satisfactory results regarding the validity and reliability of SOHO-5, the majority of the included studies did not report all domains of the cross-cultural adaptations and psychometric properties. Overall, the quality of the cross-cultural adaptations and psychometric properties of the included studies is doubtful. Future research should follow the guidelines to assess all aspects of psychometric properties and adaptation procedures in cross-cultural settings.

Principals' Perspectives on Joining a Kindergarten Outreach Dental Service: A Qualitative Study.

In this qualitative study, the researchers explored principals' perspectives on a free outreach dental service with silver diamine fluoride (SDF) therapy for children in kindergarten. Two researchers recruited kindergarten principals using purposive sampling. They conducted individual semi-structured interviews to collect the principals' perspectives regarding their adoption of and experience with the service. They manually transcribed the interview verbatim into text and followed a thematic approach for data analysis. The researchers interviewed eight principals. The principals identified the prevalent caries status and importance of oral health promotion for kindergarten children. They acknowledged that the service enhanced dental knowledge, fostered oral hygiene practice and improved children's oral health. To adopt this service, they needed to ensure adequate capacity to perform the service. They had no concern with staining by SDF because the parents were informed and consented to the SDF therapy. They appreciated the free service provided by a professional team managed by a reputable university. In conclusion, the principals were generally satisfied with the outreach dental service. They realised the necessity of oral health promotion. They found that parents accepted the SDF therapy although the SDF stained their children's carious teeth. They needed support from their teachers and the children's parents to run the service.

Silver diamine fluoride therapy for dental care.

Silver diamine fluoride (SDF) was developed in Japan in the 1960s. It is used to control early childhood caries, arrest root caries, prevent fissure caries and secondary caries, desensitise hypersensitive teeth, remineralise hypomineralised teeth, prevent dental erosion, detect carious tissue during excavation and manage infected root canals. SDF is commonly available as a 38% solution containing 255,000 ppm silver and 44,800 ppm fluoride ions. Silver is an antimicrobial and inhibits cariogenic biofilm. Fluoride promotes remineralisation and inhibits the demineralisation of teeth. SDF also inactivates proteolytic peptidases and inhibits dentine collagen degradation. It arrests caries without affecting dental pulp or causing dental fluorosis. Indirect pulp capping with SDF causes no or mild inflammatory pulpal response. However, direct application of SDF to dental pulp causes pulp necrosis. Furthermore, SDF stains carious lesions black. Patients must be well informed before SDF treatment. SDF therapy is simple, painless, non-invasive, inexpensive, and requires a simple armamentarium and minimal support. Both clinicians and patients generally accept it well. In 2021, the World Health Organization included SDF as an essential medicine that is effective and safe for patients. Moreover, it can be used for caries control during the COVID-19 pandemic because it is non-aerosol-generating and has a low risk of cross-infection.

Parental perspectives on the use of silver diamine fluoride therapy to arrest early childhood caries in kindergarten outreach dental services: A qualitative study.

OBJECTIVES: This study aimed to explore parental perspectives on an outreach dental service and silver diamine fluoride (SDF) therapy to arrest and prevent early childhood caries. METHODS: This qualitative study collaborated with an outreach service offering SDF therapy to kindergarten children and oral health education to the children's parents. The study was conducted in 2018 using purposive sampling of participating parents from selected kindergartens in Hong Kong until data saturation was reached. Five parents were recruited from each kindergarten for a focus-group discussion. The data were manually coded for thematic analysis. RESULTS: Ten focus-group discussions with 49 parents were held to achieve data saturation. The oral health education largely met the parents' expectations regarding enriching their child's oral health knowledge, raising their child's dental awareness, and promoting parent-assisted toothbrushing. Some parents did not consent to their children undergoing SDF therapy because it permanently stains caries black, which adversely affects appearance. They were also concerned about potential toxicity of SDF. Parents who did consent preferred the arrest and prevention of dental caries over aesthetics which are temporary until the primary teeth exfoliate. CONCLUSIONS: This outreach dental service improved parental dental knowledge. Some parents were generally satisfied with the outreach dental services, preferred caries arrest over aesthetics, and accepted SDF therapy. However, some parents worried about SDF toxicity. The results of this study provide rich, in-depth, and multi-dimensional information about parents' experiences of taking the outreach dental service and their opinions about SDF therapy. CLINICAL SIGNIFICANCE: Dentists can use the arguments from this study to form a protocol for communicating with parents before SDF therapy. This study shows that outreach dental services improve dental knowledge. Some parents prefer caries arrest over aesthetics and accept SDF therapy; however, some parents worry about SDF toxicity.

A Review of the Protocol of SDF Therapy for Arresting Caries.

OBJECTIVE: The aim of this work was to review the protocol of the use of silver diamine fluoride (SDF) for arresting caries, specifically the application time. METHOD: Two researchers searched manufacturers' instructions, YouTube videos, and 5 databases (Embase, Medline, PubMed, Scopus, and Web of Science). Manufacturers' instructions, videos from national dental organisations, and peer-reviewed journal articles that published the SDF application protocol in English for arresting caries were selected. RESULTS: The review included 14 protocols from 15 publications from 4 manufacturers, 3 dental associations, and 7 author teams (one team had 2 articles). The American Dental Association and the British Society of Paediatric Dentistry provided their SDF application protocols on YouTube. The American Academy of Paediatric Dentistry and 7 author teams published their protocols in journal articles. Seven publications suggested an SDF application time of 60 seconds. Seven publications suggested a time range of 10 seconds to 240 seconds. Two publications suggested caries excavation, but 4 publications suggested no caries excavation before SDF application. The procedures from at least 5 publications involved protecting the gingiva with petroleum jelly, isolating the carious tooth with cotton rolls, drying the carious lesion with a 3-in-1 syringe, applying SDF solution with a micro brush for 60 seconds, removing excess SDF solution with gauze, and applying fluoride varnish to the SDF-treated lesion. CONCLUSIONS: Although the SDF application protocol is simple and straightforward, the published protocols could be different. Most publications suggested an SDF application time of 60 seconds, which can be long, particularly for young children and older adults.

Ion Concentration of Silver Diamine Fluoride Solutions.

OBJECTIVE: The aim of this work was to determine the free fluoride and silver ion concentrations and the alkalinity of 4 commercially available 38% silver diamine fluoride (SDF) solutions. METHODS: Four common brands of 38% SDF solutions, namely Saforide, Advantage Arrest, e-SDF, and Topamine, were selected. Three bottles of each brand of SDF solution from the same lot were assessed. Measurements of the silver and fluoride content and alkalinity were performed directly when a bottle was opened. Each measurement was repeated to recheck its reliability. The free fluoride ion concentrations were measured using a calibrated ion-selective electrode. The free silver ion concentrations were measured using optical emission spectrometry. The alkalinity of the SDF solution was determined with a pH electrode. RESULTS: The mean concentrations of fluoride ions of the Saforide, Advantage Arrest, e-SDF, and Topamine were 43,233 ppm, 44,333 ppm, 51,370 ppm, and 54,400 ppm, respectively; their percentage differences from the expected value (44,800 ppm) were 3.5%, 2.4%, 14.7%, and 21.4%, respectively. The mean concentrations of silver ions of the Saforide, Advantage Arrest, e-SDF, and Topamine were 258,841 ppm, 260,016 ppm, 336,149 ppm, and 319,966 ppm, respectively; their percentage differences from the expected value (253,900 ppm) were 3.2%, 5.8%, 32.4%, and 25.9%, respectively. The 4 products had pH values of 9.2, 9.1, 9.2, and 9.0, respectively. CONCLUSIONS: This study showed differences between the claimed and measured fluoride and silver ion concentrations in 4 common 38% SDF products, which were alkaline with a pH value of 9.

Fluoride Delivered via a Topical Application of 38% SDF and 5% NaF.

OBJECTIVES: The objectives of this study were to compare the amount of fluoride delivered via a topical application of 38% silver diamine fluoride (SDF) solution and 5% sodium fluoride (NaF) varnish as well as to determine the amount of 38% SDF solution delivered using various micro-applicators. METHODS: The weights of 38% SDF (Saforide) and 5% NaF (Duraphat) applied to the occlusal surface of an extracted human upper first premolar with a regular-size (2.50-mm tip diameter) micro-applicator were measured using an electronic-analytical balance. Afterwards, the weight of 38% SDF applied to a premolar using the micro-applicators of 5 common brands (Premium Plus, 3M, Dentsply, Elevate Oral Care, and SDI) were studied. The tip diameter of each micro-applicator was measured under a microscope. The weights of the delivered fluoride and silver were also calculated. RESULTS: The mean weights of the fluoride delivered via the SDF solution and NaF varnish were 0.25 ± 0.07 mg and 0.49 ± 0.08 mg, respectively (P < .001). In addition, the tip diameters of the micro-applicators ranged from 1.89 ± 0.03 mm to 2.76 ± 0.02 mm. The mean weights of the fluoride delivered per application of 38% SDF using different applicators ranged from 0.13 ± 0.06 mg to 0.30 ± 0.09 mg, whereas the mean weights of the silver ranged from 0.76 ± 0.32 mg to 1.68 ± 0.50 mg. The weights of the delivered 38% SDF solution varied with the brand and with the tip diameters of the dental micro-applicators (P < .001). CONCLUSIONS: The fluoride of the 38% SDF solution delivered topically was significantly less than that of 5% NaF varnish. Moreover, the amount of SDF solution delivered depends on the brand and size of the micro-applicators.

Effectiveness of Silver Diamine Fluoride for Preventing Occlusal Caries in the Primary Teeth of Preschool Children: Protocol for a Randomized Controlled Trial.

BACKGROUND: Tooth decay is a significant public health problem globally. The caries-arrest effectiveness of 38% silver diamine fluoride (SDF) has been well documented. However, information on the caries-preventive effect of SDF on primary teeth is insufficient. OBJECTIVE: The aim of this trial is to investigate the effectiveness of semiannual application of 38% SDF and that of 5% sodium fluoride (NaF) varnish when compared with placebo control for preventing occlusal caries in the primary molars of preschool children over 30 months. METHODS: This 3-arm, parallel design, double-blind, randomized controlled trial involves 791 preschool children. Children are randomly allocated to receive 1 of 3 interventions as follows: Group 1, 38% SDF; Group 2, 5% NaF varnish; and Group 3, placebo control (tonic water). The intervention and dental examination will be carried out every 6 months. A parent-administered questionnaire, including the children's demographic background and oral health-related behaviors, has been collected at baseline. Follow-up examinations to detect new caries development will be conducted every 6 months by a masked examiner. Caries development will be diagnosed at the cavitation level. Chi-square tests and logistic regression analyses will be adopted. A 2-level logistic regression analysis will be performed to investigate the effects of the study interventions and other potential confounding factors on the development of occlusal caries. RESULTS: This study was started on September 1, 2020, and the recruitment process ended on September 30, 2021. At present, a total of 791 children are participating in the study. This 30-month clinical trial is expected to be completed in March 2024. CONCLUSIONS: If SDF application is more effective than NaF varnish for preventing caries on occlusal surfaces of primary teeth, it can be a preferred choice for caries prevention in a kindergarten-based program. Results of this trial will provide valuable clinical evidence for the development of oral health strategies and policies on the promotion of child oral health. TRIAL REGISTRATION: HKU Clinical Registry HKUCTR-2844, https://tinyurl.com/bdhz9yuk; ClinicalTrials.gov NCT05084001, https://clinicaltrials.gov/ct2/show/NCT05084001. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/35145.

Effect of application time of 38% silver diamine fluoride solution on arresting early childhood caries in preschool children: a randomised double-blinded controlled trial protocol.

BACKGROUND: To study the caries lesion activity response to topical 38% silver diamine fluoride (SDF) therapy with increasing treatment application time. METHODS/DESIGN: The design is a stratified-randomised, double-blind, active-controlled, parallel-group clinical trial with nine treatment arms. The trial will involve recruiting at least 414 3- to 5-year-old kindergarten children with caries, who will receive approximately 0.004 mL of 38% SDF (the typical amount applied per the manufacturer's instructions) to treat each caries lesion. The children will be stratified by caries status, randomised by blocks, and allocated to nine groups of SDF application times: 3, 5, 10, 15, 30, 45, 60, 120, and 180 s. The outcome measure is caries lesion activity (active/arrest) at the tooth-surface level at 6 months post-initial treatment. A calibrated dentist will conduct the blinded clinical examinations at baseline and at the 6-month follow-up. In addition, the parents will be surveyed to examine the effects of the moderating variables, such as oral hygiene, on caries lesion activity. The hypothesis is that a monotonically increasing trend can be found between the SDF application time and the proportion of caries lesions that are arrested. The Cochran-Armitage test for trends in proportions, corrected for clustering within children, will be used to determine the relationship between the exposure to SDF (the SDF application time) and the response (proportion of lesions arrested) in children, taking into consideration the effect of the moderating variables as well as the nesting of multiple caries lesions within an individual child. An EC 80 analysis (an 80% maximal concentration) will be used to determine the exposure (the SDF application time) for 80% caries lesion arrest. Bootstrap methods will be used for clustered data and will be resampled by clustering to determine the 95% confidence interval. DISCUSSION: This study will help with determining the optimal application time for SDF treatment. It will provide an evidence-based protocol for the use of SDF to arrest tooth decay in the primary teeth of young children. The results will inform an evidence-based SDF protocol to arrest caries, which affects 573 million children with tooth decay worldwide. TRIAL REGISTRATION: ClinicalTrials.gov NCT04655430 . Registered on 7th December 2020.

Prevalence of Untreated Early Childhood Caries of 5-Year-Old Children in Hong Kong: A Cross-Sectional Study.

This cross-sectional survey investigated untreated early childhood caries (ECC) and its associated factors among 5-year-old children in Hong Kong. Children were recruited using a multistage sampling method. One dentist examined the children in kindergarten to diagnose untreated ECC (dt) at the cavitation level. Each child's demographic information, snacking behaviour, and oral health-related practice were collected using a parental questionnaire. The relationships between the untreated ECC and demographic information, snacking behaviours, and oral health--related practice were analysed by zero-inflated negative binomial (ZINB) regression analysis. This survey recruited 404 children. Their dt score was 2.8 ± 3.8. The significant untreated ECC (SiUC) index, which was one-third of the children with the highest dt score, was 7.1 ± 3.6. Their untreated ECC prevalence was 57%, which was associated with the district the child lived in. Most children with untreated ECC (71%, 164/231) had never visited a dentist. Children who brushed without toothpaste had more untreated ECC. Children coming from low-income families and with a lower maternal education level had a higher risk of ECC. In conclusion, untreated ECC was prevalent and unevenly distributed among 5-year-old children in Hong Kong. Its prevalence was associated with toothpaste use, family income, maternal education level and the district they lived in.