Ion release of the glass ionomer restoration with silver diamine fluoride dentin pretreatment

OBJECTIVE

To assess the fluoride and silver ion release of glass ionomer cement (GIC) restorations, including conventional GIC (CGIC) and resin-modified GIC (RMGIC) restorations, with 38 % silver diamine fluoride (SDF) solution dentin pretreatment.

METHODS

Eighty dentin blocks were allocated into 4 groups and restored with SDF+CGIC, CGIC, SDF+RMGIC and RMGIC, respectively. Each block was stored in deionized water at 37 °C for 2 years. Fluoride and silver ion concentration in storage solution was measured using ion-selective electrode and inductively coupled plasma-optical emission spectrometry for up to 2 years. The cross-sectional surfaces of restored dentin blocks were assessed by X-Ray diffraction analysis (XRD), scanning electron microscope (SEM) with energy-dispersive X-ray spectroscopy (EDS) after 1 week and 2 years, respectively.

RESULTS

The mean ± standard deviation (SD) of accumulative fluoride releasing in SDF+CGIC, CGIC, SDF+RMGIC and RMGIC for 2 years were 0.13±0.005 mg, 0.09±0.006 mg, 0.15±0.008 mg and 0.05±0.003 mg, respectively (Groups SDF+RMGIC > SDF+CGIC > CGIC >RMGIC, p < 0.05). The mean ± SD of accumulative silver releasing in SDF+CGIC, CGIC, SDF+RMGIC and RMGIC for 2 years were 0.03±0.009 mg, 0.00±0.00 mg, 0.01±0.003 mg, and 0.00±0.00 mg, respectively (Groups SDF+CGIC > SDF+RMGIC > CGIC&RMGIC, p < 0.05). Groups SDF+CGIC and SDF+RMGIC showed sustainably higher fluoride and silver releasing compared to Groups CGIC and RMGIC (p < 0.05). XRD analysis indicated the fluorapatite and silver chloride were observed only in Groups SDF+CGIC and SDF+RMGIC, but not in Groups CGIC and RMGIC. SEM images of the cross-sectional view of the dentin blocks showed silver crystals within dentinal tubules 1 week and 2-year in Groups with SDF pretreatment.

CONCLUSION

The 38 % SDF dentin pretreatment sustainably increased the fluoride and silver release of GIC and RMGIC restorations for up to 2 years.

VMT/ACP/Dextran composite nanosheets against dental caries through promoting mineralization of dentin tubules, pH buffering, and antibacterial

Dental caries is a worldwide public healthcare concern, and is closely related to the acidic environment that caused by bacterial decomposition of food. In this study, a two-step ion exchange liquid-phase stripping method was applied to strip out vermiculite (VMT) nanosheets, then amorphous calcium phosphate (ACP) and dextran were inserted between the VMT nanosheets interlayer to obtain a composite two-dimension nanosheets (VMT/ACP/Dextran). VMT/ACP/Dextran composite nanosheets exhibited excellent biocompatibility and could provide exogenous Ca2+and PO43- from ACP, provide SiO44-, Mg2+, Fe2+ and obtain buffering pH and antibacterial properties from VMT, as well as improve suspension stability and targeting Streptococcus mutans through glucan. The in vitro study showed that the composite materials could promote the mineralization and sealing of dentin tubules by releasing active ions, buffer pH 4.5 (a value close to the pH in the dental plaque environment) to pH 6.6-7.1 (values close to the pH in human saliva) through ion exchange, and exert antibacterial effects by targeting Streptococcus mutans and exerting oxidase like and peroxidase like activities to produce reactive oxygen species (ROS). The in vivo animal study showed that daily cleaning teeth using VMT/ACP/Dextran composite nanosheets could effectively reduce the incidence rate and severity of dental caries in rats. Taking together, the developed VMT/ACP/Dextran composite nanosheets, which integrated the excellent properties of VMT, ACP and dextran, can effectively prevent dental caries through a combination of factors such as buffering acids, antibacterial properties, and promoting calcification, and may be used as an active ingredient for daily oral hygiene or filling materials to prevent and treat dental caries.

Effects of light curing on silver diamine fluoride-treated carious lesions: A systematic review

OBJECTIVE

This systematic review aims to evaluate the potential benefits and underlying mechanisms of combining SDF with light curing, based on available studies.

MATERIALS AND METHODS

A systematic search of publications was conducted with the keywords "silver diamine fluoride" or "silver fluoride" and "dental light curing," "LED curing," "dental laser," and "dental polymerization" in 4 databases: PubMed, EBSCO, Scopus, and Google Scholar to identify English-language articles published up to March 2023. Duplicate publications were deleted. Two reviewers screened the titles and abstracts and excluded irrelevant publications. The full text of the remaining publications was retrieved. Studies investigating the effect of light-curing on SDF-treated carious lesions were included.

RESULTS

The 175 publications initially found included 5 laboratory studies investigating the effects of light curing on 38% SDF-treated dentine carious lesions, but no clinical study was found. Four of these studies were conducted on extracted primary teeth, and one was on extracted permanent teeth. SDF with light curing increased microhardness (n = 3, p < .05) showed a higher mineral density (n = 1, p < .041) and had more silver ion precipitation in infected dentine (n = 1, p < .016) compared to SDF without light curing. Moreover, no significant differences in the antibacterial activity were observed between SDF with light curing and SDF alone (n = 1, p > .05).

CONCLUSION

Drawing from the limited number of laboratory studies, incorporating light curing subsequent to the SDF application yields potential favorable outcomes that include augmented microhardness, elevated mineral density, and heightened silver ion precipitation within infected dentine. Future clinical research is required to confirm or refute the benefit of light curing on SDF-treated carious lesions.

Diffusion of Silver Diamine Fluoride Solution in Dentine: An In Vitro Study

OBJECTIVES

The aim of this research was to assess the diffusion dynamics of silver and fluoride ions after 38% silver diamine fluoride (SDF) solution application on dentine of varying thicknesses over 24 weeks.

METHODS

Bovine dentine discs of 5.5 mm in diameter were prepared and separated into 3 groups with thicknesses of 0.5 mm (group 1), 1.0 mm (group 2), and 1.5 mm (group 3). The diameter and number of dentinal tubules of discs were assessed. Each disc received a topical application of 0.05 mL 38% SDF solution. The deionised water in the tube was collected weekly for 24 weeks. The silver and the fluoride ion concentrations in the collected deionised water were determined. Generalised estimating equations was used to explore the potential effects of the key factors on the silver/fluoride diffusion.

RESULTS

The amount of silver and fluoride ion diffusion through dentine almost levelled off after 4 weeks and showed a decline trend over 24 weeks. The mean (SD) 24-week cumulative ion diffusion through dentine in groups 1, 2, and 3 was as follows: 20 (4) μg, 10 (2) μg, and 5 (1) μg for silver (P < .05) and 18 (2) μg, 13 (2) μg, and 7 (1) μg for fluoride (P < .05), respectively.

CONCLUSIONS

Silver and fluoride ion diffusion through dentine showed a decline trend over 24 weeks. The diameter and the number of dentinal tubules on dentine with different thicknesses affects the ion diffusion dynamics. This study provides indications on the pattern of silver/fluoride ions diffusion through dentine to pulp after 38% SDF application. An increased amount of silver/fluoride diffuses through dentine into the pulp with decreased remaining dentine thickness.

The effect of silver diammine fluoride on In Vitro Enamel caries lesion remineralization and staining as a function of lesion baseline mineral distribution

OBJECTIVES

to investigate whether baseline mineral distribution modulates the ability of silver diammine fluoride (SDF) to remineralize and stain enamel caries lesions.

METHODS

This laboratory study followed a 3 [treatment: SDF/fluoride varnish (FV)/deionized water (DIW)] ×3 [lesion protocol: methylcellulose (MeC)/hydroxyethylcellulose (HEC)/Carbopol 907 (C907)] factorial design. Lesions were created in bovine enamel specimens (n = 20). Treatments were applied and lesions remineralized in artificial saliva. Digital transverse microradiography (TMR-D) was used to analyze lesions. Lesion color was monitored spectrophotometrically. The effects of lesion protocol and treatment on changes in lesion depth (ΔLD), mineral loss (ΔΔZ), maximum mineral density at the surface zone (ΔSZmax), and color changes related to remineralization (ΔL*remin) were analyzed using two-way ANOVA.

RESULTS

The treatment×lesion protocol interaction was significant for ΔΔZ (p < 0.01) and ΔL*remin (p < 0.01), however not for ΔLD (p = 0.23) or ΔSZmax (p = 0.91). There were no differences in ΔΔZ between treatments in HEC and C907 lesions. However, DIW resulted in more remineralization than both SDF (p < 0.01) and FV (p = 0.01) in MeC lesions. Considering changes from lesion baseline after remineralization in MeC lesions, SDF treatment resulted in the highest mineral gain in the surface zone. However, DIW revealed the highest mineral gain after remineralization in the lesion body. SDF stained lesions with the intensity increasing after remineralization in C907 lesions, whereas staining decreased in MeC and HEC lesions.

CONCLUSION

High fluoride treatments can interfere with continuous remineralization of caries lesions due to partial arrest. Baseline lesion mineral distribution affects SDF's ability to enhance remineralization and the staining caused by SDF.

CLINICAL SIGNIFICANCE

SDF is being used to arrest active caries lesions extending into dentin and to treat dentin hypersensitivity. This study shed light on SDF's effect on an isolated process in dental caries only, remineralization. It achieved this by examining enamel caries lesions with differing mineral distributions and assessing their staining properties.

Permanent and decidua dentition as chronological biomarkers of heavy metal contamination: A review of the forensic literature

STATEMENT OF PROBLEM

Contamination with heavy metals (HM) has great environmental consequences in the environment due to lack of biodegradation, in addition, accumulation in living beings causes defects in tissues and organs, deteriorating their function and inducing a wide spectrum of diseases. Human biomonitoring consists of the periodic measurement of a certain chemical substance or metabolite in a particular population, using matrices that can be acute or chronic. Teeth are chronic matrices that have great characteristics of resistance and chronological storage of information. This review aims to identify the mechanisms, spatial location, and affinity of HM within teeth, along with understanding its applicability as a chronological record matrix in the face of HM contamination.

MATERIAL AND METHODS

A systematic search review was performed using the PubMed/Medline, Web of Science, and Scopus metasearch engines, and the terms "teeth" OR "dental" OR "tooth" AND "heavy metals" were intersected. Complete articles are included in Spanish, English and Portuguese without time restrictions, involving studies in humans or in vitro; Letters to the editor, editorials and those that did not refer to information on the incorporation and relationship of HM with the teeth were excluded.

RESULTS

837 published articles were detected, 91 were adjusted to the search objective, and 6 were manually included. Teeth are structures with a great capacity for information retention in the face of HM contamination due to low physiological turnover and their long processes of marked formations by developmental biorhythm milestones such as the neonatal line (temporal reference indicator). The contamination mechanisms inside the tooth are linked to the affinity of hydroxyapatite for HM; this incorporation can be in the soft matrix during the apposition phase or as part of the chemical exchanges between hydroxyapatite and the elements of the environment.

CONCLUSION

The teeth present unique characteristics of great resistance and affinity for HM, as well as a chronological biomarker for human biomonitoring, so they can be used as means of expertise or evidence to confirm or rule out a fact of environmental characteristics in the legal field.

Silver modified atraumatic restorative treatment: a paradigm shift in dental caries management

Silver diamine fluoride (SDF) and atraumatic restorative treatment (ART) are treatment modalities that are minimally invasive and used for the prevention and control of dental caries. The amalgamation of these two techniques has led to the development of silver modified atraumatic restorative treatment (SMART). In this approach the carious lesion is restored with glass-ionomer cement (GIC) after SDF application. SMART effectively arrests caries without removing additional tooth structure, making it a promising option for caries management in children who lack cooperative ability.This article reviews the literature on SMART, the evidence regarding its applications in dental practice, its advantages, drawbacks, the scope for research, and clinical use.

Chemical kinetics of silver diammine fluoride in demineralization and remineralization solutions-an in vitro study

Introduction

Silver Diammine Fluoride (SDF) is a clinical minimal intervention to manage dentin caries. Its chemistry in demineralization conditions has been investigated widely, but far less in remineralization conditions. The aim was to investigate and compare the chemical reactions when SDF is added to remineralization and demineralization solutions.

Methods

0.01 ml SDF (Riva Star) was added to deionized water (DW); demineralization (DS = pH4) and remineralization (RS = pH7.0) solutions. The time sequence of concentrations of NH4+, F-, and Ag+ were measured using ion selective electrodes (ISEs) every 2 min. The pH was also measured. Precipitates were characterized using x-ray Diffraction (XRD) and, 31P and 19F nuclear magnetic resonance spectroscopy (NMR).

Results

The concentrations of NH4+ and Ag+ showed decreasing trends in DW (-0.12 and -0.08 mM/h respectively), and in DS (-1.06 and -0.5 mM/h respectively); with corresponding increase in F- concentration (0.04 and 0.7 mM/h respectively). However, in RS, NH4+ concentration showed little change (0.001 mM/h), and Ag+ and F- concentrations were negligible. XRD results showed that precipitates (in RS only) contained AgCl, and metallic Ag. NMR showed that fluorapatite/carbonated fluorapatite (FAP/CFAP) were formed. The pH increased after SDF addition in all three solutions.

Discussion

SDF dissolved to release NH4+, F- and Ag + . In DW and DS, NH4+ combined with Ag+ to form diamminesilver, causing an increase of F- and pH. In RS, F- reacted with Ca2+ and (PO)43- to form FAP/CFAP, and Ag+ reacted with Cl- to form AgCl/Ag. These suggests why SDF is effective in managing dentin caries.

Efficacy of 38% silver diamine fluoride in reducing gingival inflammation and plaque accumulation in older adults living in retirement-homes: A randomized controlled pilot trial

OBJECTIVES

Emerging from earlier case reports the potential benefits of 38 % silver diamine fluoride (SDF) in addressing pathogenic biofilms and mitigating gingival inflammation and enlargement have sparked interest. Our study aimed to evaluate the efficacy of 38 % SDF in reducing gingival inflammation and plaque accumulation in older adults living in retirement-homes.

METHODS

This 7-week randomized, controlled, double-blinded pilot trial employed a parallel assignment design. The study enrolled older adults (aged ≥65) residing in retirement homes in Dallas County, ultimately comprising a cohort of 40 participants who were evenly divided into two arms. The experimental group received SDF treatment, whereas the comparator group received a placebo. Over three consecutive weeks, both groups had solutions applied to the facial surfaces of all their teeth once per week. The primary outcomes measured the change in Löe-Silness Gingival Index (GI) and Silness-Löe Plaque Index (PI) at 7 weeks following baseline treatment. Repeated measures ANOVA was utilized to assess changes over time within each group (n = 15 each). Post-hoc paired t-tests were conducted to compare changes between week 1 and each subsequent follow-up time point (weeks 3, 5, 7), supplemented with 95 % confidence intervals for change from week 1.

RESULTS

In the SDF group, within-group comparisons demonstrated significant reductions (adjusted p < .05) in GI scores within 3 weeks (-.93±.37), as opposed to week 1 (1.90±.39). Between-group comparisons unveiled reductions in both mean GI (p < .05) and PI (p < .05), indicating less gingival inflammation and plaque accumulation in the SDF group at all time points, commencing at week 3.

CONCLUSIONS

This study showed that 38 % SDF was effective in reducing gingival inflammation and plaque accumulation in older adults living in retirement-homes.

CLINICAL SIGNIFICANCE

Oral health in older adults is a public health concern, especially for the medically compromised or those without traditional care. Our findings offer hope for enhancing oral health quality of life by introducing a cost-effective, compliance-free, noninvasive, and accessible therapeutic.

TRIAL REGISTRATION

NCT03445286.(clinicaltrials.gov).

Silver Compounds for Caries Management

Silver metal and compounds have antibacterial properties, although their action's mechanisms are not fully understood. Scientists generally consider that silver disrupts the bacterial cell wall. It causes a structural change in the bacterial cell membrane and cytoplasm. It also stops deoxyribonucleic acid replication, resulting in inactivating enzymatic activity and cell death. The antimicrobial effect of silver-containing compounds relies on the release of bioactive silver ions. Hence, silver metal and compounds have been used in medicine to prevent infection for hundreds of years. Silver metal and compounds are also used as antibacterial agents in dentistry. Studies have shown that silver compounds are effective in the management of dental caries. Fluoride-containing silver compounds have been found in experiments to be beneficial at remineralising dental cavities. Silver diamine fluoride (SDF) can assist in preventing and arresting tooth cavities. The World Health Organization included SDF in its Model List of Essential Medicine for both adults and children in 2021. Clinicians also use SDF to manage dentine hypersensitivity as well as to inhibit growth of periodontal pathogens. However, traditional silver compounds cause tooth discolouration because of the silver-staining effect. These side effects of their applications depend on the amount applied and the frequency of application. Researchers are developing nanosilver fluoride and silver nanoparticles to overcome the staining. This review gives an overview of the antibacterial mechanism of silver compounds, namely silver nitrate, silver fluoride, SDF, silver nanoparticles, and nano silver fluoride for caries management. The outlook for the future development of silver compounds will be discussed.

Effect of light curing on the efficacy of silver diamine fluoride: A systematic review

Objective

This study was aimed at comparing the performance of light-cured (LC) silver diamine fluoride (SDF) to non-LC SDF in dental applications, in terms of various properties.

Methods

Articles published until April 2023 were retrieved from electronic databases (PubMed, Scopus and Science Direct) according to Boolean operators, and the reference lists of the included articles were manually searched. The included articles were all full-text, original studies in English that assessed the effects of LC SDF compared with SDF alone. The risk of bias in the in vitro studies on dental materials was evaluated with the modified Consolidated Standards of Reporting Trials (CONSORT) checklist.

Results

Six studies (five in vitro and one ex vivo) were included in qualitative analysis after a comprehensive manual search and electronic database search. Every study compared LC SDF versus non-LC SDF in terms of properties such as penetration depth, silver ion precipitation, dentine hardness, surface morphology and anti-bacterial characteristics. Four studies were categorised as low quality with a high risk of bias, whereas the remaining two studies were considered high quality with a low risk of bias.

Conclusion

In this investigation, LC SDF, compared with non-LC SDF, was found to be an efficacious approach for enhancing SDF properties. Future high-quality studies, particularly randomised clinical trials, remain necessary to verify these findings.

Clinical significance

The use of light curing with SDF can be a beneficial strategy that enhances SDF's clinical use. This review comparing various properties of LC SDF and non-LC SDF may help clinicians enhance clinical use and patient acceptance of LC SDF.

The Evolving Microbiome of Dental Caries

Dental caries is a significant oral and public health problem worldwide, especially in low-income populations. The risk of dental caries increases with frequent intake of dietary carbohydrates, including sugars, leading to increased acidity and disruption of the symbiotic diverse and complex microbial community of health. Excess acid production leads to a dysbiotic shift in the bacterial biofilm composition, demineralization of tooth structure, and cavities. Highly acidic and acid-tolerant species associated with caries include Streptococcus mutans, Lactobacillus, Actinomyces, Bifidobacterium, and Scardovia species. The differences in microbiotas depend on tooth site, extent of carious lesions, and rate of disease progression. Metagenomics and metatranscriptomics not only reveal the structure and genetic potential of the caries-associated microbiome, but, more importantly, capture the genetic makeup of the metabolically active microbiome in lesion sites. Due to its multifactorial nature, caries has been difficult to prevent. The use of topical fluoride has had a significant impact on reducing caries in clinical settings, but the approach is costly; the results are less sustainable for high-caries-risk individuals, especially children. Developing treatment regimens that specifically target S. mutans and other acidogenic bacteria, such as using nanoparticles, show promise in altering the cariogenic microbiome, thereby combatting the disease.

Penetration of SDF and AgF from the infected dentine towards the unaffected tooth structure

Background

The use of SEM-EDS line scan analysis to evaluate the movement of ions from dental materials towards the tooth structure and the concept of ion movement is well established. This analysis technique was used to determine the ion movement of two commercially available silver- and fluoride-containing products.

Methods

This study aimed to compare the elemental analysis of primary molar teeth treated with silver diamine fluoride (SDF) and water-based silver fluoride (AgF) and to analyse the penetration of SDF and AgF from the infected dentine towards the healthy dentine. The teeth were cleaned from debris and contaminants off the roots and stored until use. A total of 15 primary molars with large active cavitated lesions, not extending into the pulp (specimens), were divided into three test groups: silver diamine fluoride (SDF) (n = 5), water-based silver fluoride (AgF) (n = 5), and deionised water (W) (n = 5) as the control group. The teeth were sectioned, embedded, and received SEM-EDS line scans. The line scan had a total length of 82.65 μm. The visible end of the infected dentine and the start of the more affected dentine were chosen as the starting point to ensure that the infected caries' line distribution towards the affected dentine's transition area was as standardized as possible. Therefore, the infected dentine length of the scan was 22.80 μm (8 scan points of 2.85 μm apart), and the affected dentine, including the healthy dentine, was 59.8 μm (21 scan points). The SEM-EDS line scan from each specimen determined the average fluoride, iodide, and silver weight percentage for that specimen.

Results

The 15 sample SEM-EDS line scans were used to determine the average ion movement in wt%. The Kruskall-Wallis test and Tukey's HSD test were completed at a p < 0.05. SDF and AgF presented no significant fluoride movement in terms of the weight percentage. There was, however, significantly more fluoride movement from infected caries to the healthy dentine with SDF and AgF (p = 0.0010053) compared to the control specimens treated with deionised water. There was no significant difference between SDF and AgF for the movement of the iodide (p = 0.5953) and silver (p = 0.3708) from infected caries to the healthy dentine.

Conclusion

SDF and AgF easily penetrated through infected caries and affected tooth structure to the healthy dentine for the line scan of 82.65 μm. There was no significant difference between SDF and AgF for the movement of ions within the infected dentine nor in the affected/healthy dentine.

Pulp cell response to the application of silver diamine fluoride and potassium iodide on caries-like demineralized dentin

OBJECTIVES

To investigate the response of pulp cells to the application of silver diamine fluoride (SDF) and potassium iodide (KI) on demineralized dentin.

MATERIALS AND METHODS

The occlusal surfaces of human dentin discs (0.4 mm thick) with similar permeability were subjected to an artificial caries protocol, and then the discs were adapted into artificial pulp chambers. MDPC-23 cells were seeded on the healthy pulp dentin surface, while the demineralized surface was treated with SDF, KI, SDF + KI, or hydrogen peroxide (positive control-PC) (n = 8). The negative control (NC) received ultrapure water. After 24 h, cell viability (alamarBlue) and morphology (SEM) were evaluated. The extracts were then applied to new MDPC-23 cells seeded in culture plates to assess their viability and the formation of mineralized nodules (MN; Alizarin Red) after seven days. The data were analyzed using one-way analysis of variance/Tukey or Games-Howell tests (α = 5%).

RESULTS

SDF and PC significantly reduced the viability of cells seeded on discs (45.6% and 71.0%, respectively). Only cells treated with SDF or PC detached from the dentin substrate, while the remaining cells showed altered morphology. Cells in contact with extracts showed less reduction in viability, but it was still more toxic compared to NC. Only PC reduced MN deposition. SDF + KI or KI alone did not affect the cell response.

CONCLUSIONS

SDF applied alone showed a mild to moderate transdentinal cytotoxic effect on pulp cells. However, the combination of SDF + KI reduced the cytotoxic effects. Both materials used alone or in combination did not affect the mineralization ability of pulp cells.

CLINICAL RELEVANCE

Besides improving esthetic results, associating potassium iodide with silver diamine fluoride may reduce the transdentinal cytotoxic effects of this cariostatic agent on pulp cells.

Application of 20% silver nanoclusters in polymethacrylic acid on simulated dentin caries; its penetration depth and effect on surface hardness

The aims of this study were: To evaluate the surface hardness of simulated dentin caries lesions treated with either silver nanoclusters (AgNCls) synthesized in polymethacrylic acid (PMAA) or 38% silver diammine fluoride (SDF), as well as observe the penetration of the treatment solutions into the simulated caries lesions. Dentin blocks 4 mm thick obtained from caries-free third molars were sectioned and then simulated caries lesions on the occlusal dentin surfaces were created. Each specimen (n = 8) was divided into four sections: (A) treated with 20% AgNCls/PMAA; (B) treated with SDF 38% (FAgamin, Tedequim, Cordoba, Argentina); (C) sound tooth protected by nail-varnish during artificial caries generation (positive control); and (D) artificial caries lesion without surface treatment (negative control). AgNCls/PMAA or SDF were applied on the simulated lesions with a microbrush for 10 s, then excess removed. The surface hardness was measured by means of Vickers indentation test. To trace the depth of penetration, up to 400 μm, of silver ions, elemental composition of the samples was observed using EDX, coupled with SEM, and measured every 50 μm from the surface towards the pulp chamber. Laser Induced Breakdown Spectroscopy (LIBS) was also employed to trace silver ion penetration; the atomic silver line 328.06 nm was used with a 60 μm laser spot size to a depth of 240 μm. Student's-t test identified significant differences between treatment groups for each depth and the Bonferroni test was used for statistical analysis of all groups (p < 0.05). Mean surface hardness values obtained were 111.2 MPa, 72.3 MPa, 103.3 MPa and 50.5 MPa for groups A, B, C and D respectively. There was a significant difference between groups A and C compared with groups B and D, the group treated with AgNCls/PMAA achieved the highest surface hardness, similar or higher than the sound dentin control. A constant presence of silver was observed throughout the depth of the sample for group A, while group B showed a peak concentration of silver at the surface with a significant drop beyond 50 μm. The 20% AgNCls/PMAA solution applied to simulated dentin caries lesions achieved the recovery of surface hardness equivalent to sound dentin with the penetration of silver ions throughout the depth of the lesion.

Effects of silver diamine fluoride on demineralization protection after a secondary acid challenge

OBJECTIVE

This investigation describes the effects of 5% sodium fluoride varnish and 38% silver diamine fluoride on demineralization protection of human enamel lesions of three different severities after a secondary acid challenge.

STUDY DESIGN

Specimens underwent color and enamel surface microhardness change measurements after demineralization and treatment events. Transverse microradiography was conducted following the secondary demineralization.

RESULTS

After treatments, enamel surface microhardness change showed that 24-hour lesions treated with fluoride varnish had less rehardening than 24-hour lesions treated with silver diamine fluoride (p<0.05), whereas 144-hour lesions from both treatment groups showed a beneficial decrease in surface microhardness change that was markedly better in samples treated with silver diamine fluoride (p<0.05). After the secondary demineralization, 24- and 144-hour lesions treated with silver diamine fluoride showed a sustained beneficial decrease in enamel surface microhardness change when compared to fluoride varnish-treated samples of the corresponding lesion severity (p<0.05). Transverse microradiography showed no difference between fluoride varnish- and silver diamine fluoride-treated samples of any corresponding lesion severity, indicating that remineralization in both fluoride varnish- and silver diamine fluoride-treated samples was proportional to each other after a secondary acid challenge.

CONCLUSIONS

Using silver diamine fluoride may have comparable benefits to fluoride varnish in mineral loss prevention.

Effect of silver diamine fluoride activation on bond strength to root dentin

BACKGROUND

To investigate the effect of silver diamine fluoride (SDF) application and activation on the bond strength of gutta-percha to dentin and resin bonded post to dentin.

METHODS

Thirty-six human premolar teeth were used. The coronal part tooth was removed, and endodontic mechanical preparation was performed for all the teeth. The teeth were divided according to final rinse protocol (n = 9) as follows: Control group; no SDF application, SDF/NA; 38% SDF as a final rinse with no activation, SDF/MDA; 38% SDF as a final rinse with manual dynamic activation and SDF/US; 38% SDF as a final rinse with ultrasonic activation. Root canal obturation using lateral condensation technique followed by fiber post insertion after 48 h in the root canal after corresponding preparations. The roots were cut with a low-speed precision saw creating 2 mm thickness sections. A total of 4 sections were obtained from each tooth, 2 coronal specimens (with post) and 2 apical specimens (with Gutta percha). Each specimen was subjected to push-out bond strength test with a universal testing machine. Data were analyzed using two-way ANOVA.

RESULTS

The Push-out bond strength at the apical root section was significantly higher in SDF/MDA and SDF/US groups compared to control group. While for the coronal part, all SDF treated specimen showed reduced Push-out bond strength.

CONCLUSION

SDF application as final rinse may reduce the bonding performance between fiber post and dentine. Activation with manual and ultrasonic methods improved the bond strength at the apical root section.

Nano-CT characterization of dentinal tubule occlusion in SDF-treated dentin

Dentin hypersensitivity is an oral health concern affecting a large percentage of the world's adult population. Occlusion of the exposed dentinal tubules is among the treatment options available, and silver diammine fluoride (SDF) is an occluding agent used for interrupting or dampening the stimulus of the dental pulp nerves that produce pain. In addition to dentin permeability testing, the evaluation of desensitizing agents occluding dentinal tubules strongly relies on microscopic techniques, such as scanning electron microscopy (SEM). Limitations of SEM are that it provides only surface images that lack detailed information on the depth of penetration and amount of material present within the treated specimen, and it is prone to sample preparation artifacts. Here, we present high-resolution X-ray computed tomography (nano-CT) as a potential method for investigating dentin specimens with occluded tubules. We studied human dentin treated with SDF as an exemplary dentinal occlusion treatment option. We evaluated the silver deposits formed on the dentin surface region near the dentinal tubules and in the tubular regions using cross-section SEM, Energy Dispersive X-ray (EDX) analysis, and nano-CT. The resulting images obtained by SEM and nano-CT had comparable resolutions, and both techniques produced images of the tubules' occlusion. Nano-CT provided three-dimensional images adequate to quantitate tubule size and orientation in space. Moreover, it enabled clear visualization of dentinal tubules in any virtual plane and estimation of the amount and depth of occluding material. Thus, nano-CT has the potential to be a valuable technique for evaluating the occluding effects of virtually any material applied to dentinal tubules, supporting deciding between the best occluding treatment options.

Engineered Biomaterials Trigger Remineralization and Antimicrobial Effects for Dental Caries Restoration

Dental caries is the most prevalent chronic disease globally, significantly impacting individuals' quality of life. A key reason behind the failure of implanted restorations is their biological inactivity, meaning they are unable to form crosslinks with the surrounding tooth structures, thus making patients susceptible to implant loss and recurrent tooth decay. For the treatment of caries, antibacterial medicine and remineralization are effective means of treating the recurrence of caries. Owing to the rapid progression in the biomaterials field, several biomaterials have been reported to display antimicrobial properties and aid in dentin remineralization. Bioactive materials hold considerable potential in diminishing biofilm accumulation, inhibiting the process of demineralization, enabling dentin remineralization, and combating bacteria related to caries. Bioactive materials, such as fluoride, amorphous calcium phosphate, bioactive glass, collagen, and resin-based materials, have demonstrated their effectiveness in promoting dentin remineralization and exerting antibacterial effects on dental caries. However, the concentration of fluoride needs to be strictly controlled. Although amorphous calcium phosphate can provide the necessary calcium and phosphorus ions for remineralization, it falls short in delivering the mechanical strength required for oral mastication. Resin-based materials also offer different advantages due to the complexity of their design. In this review, we delve into the application of advanced bioactive materials for enhancing dentin remineralization and antibacterial properties. We eagerly anticipate future developments in bioactive materials for the treatment of dental caries.

Bonding performance of glass ionomer cement to carious dentin treated with different surface treatment protocols using silver diamine fluoride

This study investigated the influence of silver diamine fluoride (SDF) on the shear bond strength (SBS) to artificial carious dentin and GIC restorations with various SDF application protocols. Artificial caries were prepared on human dentin discs using bacteria model. These samples were randomly allocated to five groups (n = 10/group) according to the following treatment: (1) control group (CD): no treatment (2) CSR: dentin conditioner, SDF, and rinsing (3) CS: dentin conditioner and SDF (4) SRC: SDF, rinsing and dentin conditioner, and (5) SC: SDF and dentin conditioner. The treated-dentin surface was bonded with GIC and subjected to SBS test. Mean SBS was analyzed using one-way ANOVA. Surface morphology and elemental contents after surface treatment were examined (n = 3/group) by scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM/EDX). There was no significant difference in the mean SBS among CD (2.45 ± 0.99 MPa), CSR (1.76 ± 0.65 MPa), and SRC (2.64 ± 0.95 MPa). Meanwhile, the mean SBS of CS (0.35 ± 0.21 MPa) was significantly lower than the control and SRC group. SEM/EDX demonstrated deeper silver penetration in CSR and CS groups when compared to SRC and SC groups. SDF-modified GIC restorations resulted in significantly lower bond strength in CS and SC groups. The findings suggested treating the carious dentin surface with CSR and SRC protocol. SDF-treated carious dentin should be rinsed off prior to restore with GIC.

Caries arrest using silver diamine fluoride: Knowledge, attitude, and perception of parents in Saudi Arabia

Objectives

The objective was to assess the current knowledge, attitudes, and perceptions of parents toward the use of Silver Diamine Fluoride in children's primary teeth and identify related factors.

Materials and Methods

In this cross-sectional study, data were collected from Parents of pediatric patients who had appointments at the King Saud University Pediatric Dentistry Clinic and several private clinics in Riyadh, Saudi Arabia from Jan to April 2021. A simple random sampling method was used. An electronic questionnaire was designed to collect data regarding participants' demographics and their knowledge, attitude, and perception toward the use of SDF for their children.

Results

A higher proportion of parents/relatives (87.3%) was strongly satisfied with the speed of treatment and its benefits. In terms of disadvantages, 23.8% and 30.4% of the parents/relatives were satisfied and dissatisfied, respectively (P < 0.05). Regarding attitudes, the majority of participants 22.8% responded as neutral to using SDF to treat their children's anterior primary teeth (P < 0.05), whereas 32.2% agreed to the use of SDF in their children's posterior primary teeth (P < 0.05). A higher proportion of parents/relatives who were in the age group of >50 years (27.8%) had responded as "satisfied" compared with the responses of other age groups (P < 0.05).

Conclusion

The present study demonstrates that SDF is acceptable among Saudi parents/relatives to arrest dental caries. However, pigmentation of anterior teeth is a major concern.

Comparative Evaluation of the Remineralizing Potential of Silver Diamine Fluoride, Casein Phosphopeptide-amorphous Calcium Phosphate, and Fluoride Varnish on the Enamel Surface of Primary and Permanent Teeth: An In Vitro Study

Introduction

With the paradigm shift in the management of dental caries, the focus is now laid on remineralization therapies that can arrest the progression of the disease and remineralize the subsurface lesions.

Objectives

The purpose of this study was to determine and compare the remineralizing potential of silver diamine fluoride (SDF), casein phosphopeptide-amorphous calcium phosphate (CPP-ACP), and fluoride varnish (FV) on enamel surfaces in primary and permanent teeth.

Materials and methods

A total of 120 primary anterior teeth and 120 premolars were used to prepare enamel blocks in acrylic resin. The mean baseline surface microhardness (SMH) for each sample was determined using a microvickers hardness testing machine. Thereafter, the samples were randomly and equally distributed into groups and subgroups based on the materials used, that is, SDF, CPP-ACP, FV, and distilled water (control). After subjecting the samples to a pH cycling regime, SMH was determined again and the percentage change in SMH was calculated.

Results

The data were tabulated and subjected to statistical analysis using an independent t-test and one-way analysis of variance (ANOVA). In primary teeth, the least mean percentage reduction in SMH was observed after the application of FV followed by SDF, CPP-ACP, and control. In permanent teeth, both SDF and FV showed the least percentage reduction of enamel SMH followed by CPP-ACP and control.

Conclusion

Silver diamine fluoride (SDF), FV, and CPP-ACP showed remineralizing potential in both primary and permanent teeth.

How to cite this article

Kaur S, Bhola M, Bajaj N, et al. Comparative Evaluation of the Remineralizing Potential of Silver Diamine Fluoride, Casein Phosphopeptide-amorphous Calcium Phosphate, and Fluoride Varnish on the Enamel Surface of Primary and Permanent Teeth: An In Vitro Study. Int J Clin Pediatr Dent 2023;16(S-1):S91-S96.

Effect of silver diamine fluoride upon the microbial community of carious lesions: A scoping review

OBJECTIVES

To explore the effects of silver diamine fluoride (SDF) on the microbial community of carious lesions.

DATA

Original studies evaluating the effect of SDF treatment on the microbial community of human carious lesions were included.

SOURCES

A systematic search of English-language publications was performed in PubMed, EMBASE, Scopus, and Web of Science. Gray literature was searched in ClinicalTrials.gov and Google Scholar.

STUDY SELECTION/RESULTS

This review included seven publications reporting the effects of SDF on microbial community of dental plaque or carious dentin, including the microbial biodiversity, relative abundance of microbial taxa, and predicted functional pathways of the microbial community. The studies on microbial community of dental plaque reported that SDF did not have a significant effect on both the within-community species diversity (alpha-diversity) and inter-community microbial compositional dissimilarity (beta-diversity) of the plaque microbial communities. However, SDF changed the relative abundance of 29 bacterial species of plaque community, inhibited carbohydrate transportation and interfered with the metabolic functions of the plaque microbial community. A study on the microbial community in dentin carious lesions reported that SDF affected its beta-diversity and changed the relative abundance of 14 bacterial species.

CONCLUSION

SDF showed no significant effects on the biodiversity of the plaque microbial community but changed the beta-diversity of the carious dentin microbial community. SDF could change the relative abundance of certain bacterial species in the dental plaque and the carious dentin. SDF could also affect the predicted functional pathways of the microbial community.

CLINICAL SIGNIFICANCE

This review provided comprehensive evidence on the potential effect of SDF treatment on the microbial community of carious lesions.

Remineralization potential of phosphorylated chitosan and silver diamine fluoride in comparison to sodium fluoride varnish: invitro study

PURPOSE

The purpose of this study was to evaluate and compare the remineralization potential of phosphorylated chitosan nanoparticles (Pchi) and silver diamine fluoride (SDF) compared to sodium fluoride varnish (NaF) on microhardness of artificial carious lesions in a biomimetic minimally invasive approach that is being regarded as the future of preventive dentistry.

METHODS

The sample size included 40 intact extracted maxillary anterior human teeth. Baseline microhardness was recorded using Vickers hardness test and energy-dispersive X-ray spectroscopy (EDX). Artificial caries-like lesions were created on the exposed enamel by suspending all teeth in demineralizing solution for 10 days in a temperature of 37 °C and then the hardness and EDX were remeasured. Samples were then divided into four main groups: Group A (positive control group) n = 10, treated with NaF, Group B n = 10, treated with SDF, Group C n = 10, treated with Pchi and Group D (negative control group) n = 10 that received no treatment. After treatment, samples were incubated in artificial saliva solution at 37 °C in for 10 days and then reassessed. Data were then recorded, tabulated, and statistically analyzed using Kruskal-Wallis test and Wilcoxon signed test. Scanning electron microscope (SEM) was used to analyze the morphological changes of enamel surface after treatment.

RESULTS

Groups B and C showed the highest calcium (Ca) and phosphate (P) content as well as hardness values, while group B had the highest percentage of fluoride. SEM revealed a smooth layer of mineral formed on the surface of enamel for both groups.

CONCLUSION

Pchi and SDF showed the highest increase in enamel microhardness and remineralization potential.

CLINICAL RELEVANCE

The minimally invasive approach for remineralization could be enhanced using SDF and Pchi.

Novel bioactive dental restorations to inhibit secondary caries in enamel and dentin under oral biofilms

OBJECTIVE

To provide the first review on cutting-edge research on the development of new bioactive restorations to inhibit secondary caries in enamel and dentin under biofilms. State-of-the-art bioactive and therapeutic materials design, structure-property relationships, performance and efficacies in oral biofilm models.

DATA, SOURCES AND STUDY SELECTION

Researches on development and assessment new secondary caries inhibition restorations via in vitro and in vivo biofilm-based secondary caries models were included. The search of articles was carried out in Web of Science, PubMed, Medline and Scopus.

CONCLUSIONS

Based on the found articles, novel bioactive materials are divided into different categories according to their remineralization and antibacterial biofunctions. In vitro and in vivo biofilm-based secondary caries models are effective way of evaluating the materials efficacies. However, new intelligent and pH-responsive materials were still urgent need. And the materials evaluation should be performed via more clinical relevant biofilm-based secondary caries models.

CLINICAL SIGNIFICANCE

Secondary caries is a primary reason for dental restoration failures. Biofilms produce acids, causing demineralization and secondary caries. To inhibit dental caries and improve the health and quality of life for millions of people, it is necessary to summarize the present state of technologies and new advances in dental biomaterials for preventing secondary caries and protecting tooth structures against oral biofilm attacks. In addition, suggestions for future studies are provided.

Time-dependent structural changes and hypermineralisation of artificially demineralised dentine following treatment with silver diammine fluoride and glass ionomer cement

OBJECTIVES

This study aimed to evaluate the change of mineral content in dentine lesions over time and examine the effectiveness of the combined treatment with silver diammine fluoride (SDF) and glass ionomer cement (GIC).

METHODS

Sixty bovine dentine specimens were divided into 4 groups: cont, Fuji, Safo, and Safo+Fuji. The specimens were imaged and measured using microcomputed tomography (microCT) at 7 time points: pre-demineralisation, after demineralisation for two weeks, immediately after treatment, 1 week, 2 weeks, 1 month, and 3 months after treatment. The 3-month group was evaluated with a light microscope, attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy, and scanning electron microscope (SEM)/energy-dispersive X-ray spectroscopy (EDS). Data were analysed by Dunn's test and Wilcoxon signed rank test with Bonferroni correction for microCT, and Kruskal-Wallis test and two-way analysis of variance for EDS characterisation.

RESULTS

MicroCT images showed high mineral density beneath dentine lesions in Safo+Fuji. The mineral density at 600 μm in Safo+Fuji increased significantly over time, while Safo showed an opposite trend (adjusted p<0.005). In Safo+Fuji, EDS revealed significantly high energy of fluorine (p<0.05, at 300 μm) and a tendency towards high energy of calcium (p>0.05). However, Safo+Fuji showed lower energy of silver compared to Safo (p<0.001). ATR-FTIR revealed that phosphate groups had the highest peak at a depth between 300 and 400 μm in Safo+Fuji.

CONCLUSIONS

Safo+Fuji was effective in remineralising the deep lesion in dentine after one and three months, and a hypermineralisation zone generated beneath the lesion demonstrated additional benefit in this study.

CLINICAL SIGNIFICANCE

This long-term in vitro study showed that SDF+GIC treatment could strengthen the structure of decayed teeth when applied in the treatment of patients with advanced rampant caries.

Enhanced effectiveness of silver diamine fluoride application with light curing on natural dentin carious lesions: an in vitro study

This study aimed to compare the mean mineral density difference (mMDD) and surface morphology of 10- and 60-s silver diamine fluoride (SDF)-applied dentin carious lesions and to study the effect of an additional 20-s light curing (LC) on SDF-treated teeth. Forty primary molar blocks with natural dentin carious lesions were measured for baseline lesion depth and mineral density using Image-Pro Plus software. The samples were randomly distributed into 4 groups; 38% SDF applied for 1) 10-s (10SDF), 2) 60-s (60SDF), 3) 10-s + LC (10SDF + LC), 4) 60-s + LC (60SDF + LC) and an additional control group to assess the outcome of pH-cycling only. Then all the groups underwent a 7-d bacterial pH-cycling. The dentin carious lesions' mMDD was determined by digital subtraction radiographic analysis. The surface morphology and elemental profile were assessed by scanning electron microscopy and energy-dispersive X-ray spectroscopy. The mMDD of the dentin lesions was analyzed using two-way ANOVA, generalized linear models analysis. Light curing was the only factor that affected the mMDD (p = 0.007). The mMDD in the 10SDF + LC and 60SDF + LC groups were significantly higher than those without light curing (p = 0.041 and 0.041, respectively). The 60SDF + LC group demonstrated a significantly higher mMDD than the 10SDF group (p = 0.010), while that in the 10SDF + LC group was similar to the 60SDF group (p = 1.00). Scanning electron microscopy revealed denser mineral content layers, which were likely silver and chloride, in the 10SDF + LC and 60SDF + LC groups than in the 10SDF and 60SDF groups, respectively. In conclusion, shortened application time with light curing enhanced SDF remineralization similarly to the conventional method.

Mussel-Inspired Caries Management Strategy: Constructing a Tribioactive Tooth Surface with Remineralization, Antibiofilm, and Anti-inflammation Activity

Dental caries is a common chronic oral disease in humans resulting from tooth demineralization caused by acid production of bacterial plaque, which leads to the destruction of enamel and dentin and oral inflammation. However, it is still a challenge that the function of natural active ingredients in currently available oral care products is not comprehensive, especially the lack of remineralization. Here, inspired by the strong biological adhesion ability of mussels and ancient oral disease plant therapy, a multifunctional strategy is proposed to construct a bioactive tooth surface to treat dental caries. It has been demonstrated that the Turkish gall extract (TGE) can inhibit adhesion of cariogenic bacteria Streptococcus mutans and Actinomyces viscosus and destroy biofilms on the tooth surface. Meanwhile, TGE can reduce the expression of inflammatory factors. Notably, the TGE coating can induce the growth of hydroxyapatite (HAP) crystals in vivo and in vitro, recovering the enamel mechanical properties under normal oral conditions. MD simulations interpreted the adsorption mechanism by which the hydroxyl groups in TGE bind to phosphate group (PO₄^3-) on the tooth surface, attracting calcium ions (Ca²⁺) as nucleation sites for remineralization. This work underlines the importance of TGE coating in remineralization, antibiofilm, and anti-inflammation activity as a promising strategy for dental caries.

Older patients' perception of treating root caries with silver diamine fluoride - a qualitative study based on the Theoretical Domains Framework

OBJECTIVES

Caries treatment with silver diamine fluoride (SDF) is effective, but often leads to irreversible tooth discoloration. This study aimed to investigate older patients' perceptions of root caries treatment with SDF and to identify factors that influence their decision process.

METHODS

Fifteen interviews were conducted in older patients (mean, min/max: 83, 71/92 years) with root caries experience, following a semi-structured interview-guide based on the domains of the Theoretical Domains Framework (TDF) including three case vignettes of SDF treatment. Transcripts of the interviews were used to perform deductive and inductive content analysis along the TDF and Capability-Opportunity-Motivation-Behavior model (COM-B) to assess influential factors.

RESULTS

All TDF domains and behavior determinants of the COM-B were covered, identifying twenty-two barriers, facilitators and conflicting themes. Main barriers for consenting to SDF treatment were patients' perceptions of permanent staining of visible root caries lesions, as well as preconceptions about those of others and lack of knowledge about root caries and SDF. Main facilitators were trust in advice given by dentists, especially regarding new treatment options, that aesthetics were less important in non-visible areas and the importance of tooth preservation and feasibility of treatments when immobile or in need of care.

CONCLUSION

Permanent discoloration is an important barrier to older patients' acceptance of SDF treatment for visible root caries. However, patients appear to accept SDF treatment under certain conditions, including less visible lesions or in comparison to more invasive treatment options.

CLINICAL SIGNIFICANCE

Our findings contribute to understanding both barriers and facilitators when treating root caries in older patients with SDF.

Bioactive Materials for Caries Management: A Literature Review

Researchers have developed novel bioactive materials for caries management. Many clinicians also favour these materials, which fit their contemporary practice philosophy of using the medical model of caries management and minimally invasive dentistry. Although there is no consensus on the definition of bioactive materials, bioactive materials in cariology are generally considered to be those that can form hydroxyapatite crystals on the tooth surface. Common bioactive materials include fluoride-based materials, calcium- and phosphate-based materials, graphene-based materials, metal and metal-oxide nanomaterials and peptide-based materials. Silver diamine fluoride (SDF) is a fluoride-based material containing silver; silver is antibacterial and fluoride promotes remineralisation. Casein phosphopeptide-amorphous calcium phosphate is a calcium- and phosphate-based material that can be added to toothpaste and chewing gum for caries prevention. Researchers use graphene-based materials and metal or metal-oxide nanomaterials as anticaries agents. Graphene-based materials, such as graphene oxide-silver, have antibacterial and mineralising properties. Metal and metal-oxide nanomaterials, such as silver and copper oxide, are antimicrobial. Incorporating mineralising materials could introduce remineralising properties to metallic nanoparticles. Researchers have also developed antimicrobial peptides with mineralising properties for caries prevention. The purpose of this literature review is to provide an overview of current bioactive materials for caries management.

Insight into the development of versatile dentin bonding agents to increase the durability of the bonding interface

Despite the huge improvements made in adhesive technology over the past 50 years, there are still some unresolved issues regarding the durability of the adhesive interface. A complete sealing of the interface between the resin and the dentin substrate remains difficult to achieve, and it is doubtful whether an optimal interdiffusion of the adhesive system within the demineralized collagen framework can be produced in a complete and homogeneous way. In fact, it is suggested that hydrolytic degradation, combined with the action of dentin matrix enzymes, destabilizes the tooth-adhesive bond and disrupts the unprotected collagen fibrils. While a sufficient resin–dentin adhesion is usually achieved immediately, bonding efficiency declines over time. Thus, here, a review will be carried out through a bibliographic survey of scientific articles published in the last few years to present strategies that have been proposed to improve and/or develop new adhesive systems that can help prevent degradation at the adhesive interface. It will specially focus on new clinical techniques or new materials with characteristics that contribute to increasing the durability of adhesive restorations and avoiding the recurrent replacement restorative cycle and the consequent increase in damage to the tooth.

Dental innovations which will influence the oral health care of baby boomers

From the widespread use of smartphones and tablets to the multitude of applications available, older adults are showing an interest in utilizing technology to maintain their independence and to improve their quality of life. As technology continues to advance and be incorporated into many day-to-day activities, the baby boom generation will see these changes affecting the way they access and utilize dental services. Innovative toothbrushes and chemotherapeutics are continuing to be developed and utilized by many older adults. Within the dental office, older adults are seeing greater application of technology in every day dental procedures. These include the use of teledentistry, artificial intelligence (AI), innovative restorative materials, digitization of fixed and removable prosthodontics, cone beam computed tomography (CBCT) scans to guide dental implant placement and endodontic procedures. There is also new technology to aid in cancer detection and shielding during cancer treatment. Improved communication between the medical and dental fields has become increasingly necessary to facilitate effective patient care and a few innovative healthcare systems have begun to consolidate these services. Overall, the baby boom generation will continue to see dental innovations that will change the way they experience everyday life and dental services.

Potential Beneficial Effects of Hydroxyapatite Nanoparticles on Caries Lesions In Vitro-A Review of the Literature

Dental caries is one of the most common human diseases which can occur in both primary and permanent dentitions throughout the life of an individual. Hydroxyapatite is the major inorganic component of human teeth, consequently, nanosized hydroxyapatite (nHAP) has recently attracted researchers' attention due to its unique properties and potential for caries management. This article provides a contemporary review of the potential beneficial effects of nHAP on caries lesions demonstrated in in vitro studies. Data showed that nHAP has potential to promote mineralization in initial caries, by being incorporated into the porous tooth structure, which resulted from the caries process, and subsequently increased mineral content and hardness. Notably, it is the particle size of nHAP which plays an important role in the mineralization process. Antimicrobial effects of nHAP can also be achieved by metal substitution in nHAP. Dual action property (mineralizing and antimicrobial) and enhanced chemical stability and bioactivity of nHAP can potentially be obtained using metal-substituted fluorhydroxyapatite nanoparticles. This provides a promising synergistic strategy which should be explored in further clinical research to enable the development of dental therapeutics for use in the treatment and management of caries.

Amelioration Strategies for Silver Diamine Fluoride: Moving from Black to White

Topical cariostatic agents have become a reasonable alternative for managing dental caries in young children. Silver diamine fluoride (SDF) is a practical topical approach to arrest caries and avoid extensive and risky dental treatment. However, the literature demonstrates a parental hesitation towards accepting SDF because of black unaesthetic tooth discolouration following application. The rapid oxidation of ionic silver darkens demineralised tooth structure permanently. In this regard, nano-metallic antimicrobials could augment or substitute for silver, and thereby enhance SDF aesthetic performance. Recently, biomedical research has drawn attention to selenium nanoparticles (SeNPs) due to their antimicrobial, antioxidant, and antiviral potencies. Various in vitro studies have examined the effect of SeNPs on the virulence of bacteria. This narrative review explores practical issues when using SDF and suggests future directions to develop it, focusing on antimicrobial metals. Several methods are described that could be followed to reduce the discolouration concern, including the use of nanoparticles of silver, of silver fluoride, or of selenium or other metals with antimicrobial actions. There could also be value in using remineralising agents other than fluoride, such as NPs of hydroxyapatite. There could be variations made to formulations in order to lower the levels of silver and fluoride in the SDF or even to replace one or both of the silver and fluoride components completely. Moreover, since oxidation processes appear central to the chemistry of the staining, adding SeNPs which have antioxidant actions could have an anti-staining benefit; SeNPs could be used for their antimicrobial actions as well. Future research should address the topic of selenium chemistry to optimise how SeNPs would be used with or in place of ionic silver. Incorporating other antimicrobial metals as nanoparticles should also be explored, taking into account the optimal physicochemical parameters for each of these.

Effect of silver nanoparticles associated with fluoride on the progression of root dentin caries in vitro

OBJECTIVES

To assess the anti-proteolytic effect and potential to inhibit dentin root caries progression of a silver nanoparticle and fluoride solution (CNanoF) in comparison to silver diamine fluoride (SDF).

METHODS

48 specimens of root dentin artificial caries lesion were treated with 38% SDF, CNanoF, CNano or F (n = 6 per group). Ph cycling with demineralization and remineralization solutions simulated caries lesion progression. In addition, specimens were incubated with or without bacterial collagenase in the remineralization solution to induce dentin proteolytic degradation. Dentin degradation was assessed by weight loss rate and hydroxyproline (Hyp) release. Changes in cross-sectional microhardness, and lesion permeability and collagen integrity as determined by confocal laser scanning microscopy indicated potential for further demineralization inhibition. The effect of the solutions on the activity of metalloproteinases (MMP) -2 and -9 was also investigated. Statistical analysis consisted of ANOVA, Kruskal-Wallis, and linear mixed models with post-hoc pairwise Tukey, Dunn, and t-tests (α = 0.05).

RESULTS

Treatment with SDF resulted in lower weight loss rate than did other solutions, but all groups showed similar Hyp release (p = 0.183). SDF resulted in greater microhardness at superficial layers of the caries lesions (p<0.05), while there were no differences among CNanoF, CNano, and F. Lesion permeability was similar among all groups after pH cycling (p>0.05), with or without the use of collagenase (p = 0.58). No statistically significant difference was noted among solutions regarding collagen integrity after pH cycling; however, SDF-treated dentin had a significant decrease in collagen integrity when collagenase was used (p = 0.003). Interestingly, only SDF was able to completely inactivate MMP-2 and -9.

CONCLUSIONS

CNanoF and SDF both potentially prevent dentin degradation during caries lesion progression in vitro; however, SDF was more effective at inhibiting further tissue demineralization.

Evaluation of the remineralizing capacity of silver diamine fluoride on demineralized dentin under pH-cycling conditions

OBJECTIVE

(1) to determine the effects of the silver diamine fluoride (SDF) and sodium fluoride (NaF) in demineralized dentin exposed to an acid challenge by pH-cycling, (2) to evaluate the remineralizing capacity of SDF/NaF products based on the physicochemical and mechanical properties of the treated dentin surfaces.

METHODOLOGY

In total, 57 human molars were evaluated in different stages of the experimental period: sound dentin - negative control (Stage 1), demineralized dentin - positive control (Stage 2), and dentin treated with SDF/NaF products + pH-c (Stage 3). Several commercial products were used for the SDF treatment: Saforide, RivaStar, and Cariestop. The mineral composition and crystalline and morphological characteristics of the dentin samples from each experimental stage were evaluated by infrared spectroscopy (ATR-FTIR), X-ray diffraction, and electron microscopy (SEM-EDX) analytical techniques. Moreover, the mechanical response of the samples was analyzed by means of the three-point bending test. Statistics were estimated for ATR-FTIR variables by Wilcoxon test, while the mechanical data analyses were performed using Kruskal-Wallis and Mann Whitney U tests.

RESULTS

Regarding the chemical composition, we observed a higher mineral/organic content in the SDF/NaF treated dentin + pH-c groups (Stage 3) than in the positive control groups (Saforide p=0.03; Cariestop p=0.008; RivaStar p=0.013; NaF p=0.04). The XRD results showed that the crystallite size of hydroxyapatite increased in the SDF/NaF treated dentin + pH-c groups (between +63% in RivaStar to +108% in Saforide), regarding the positive control. SEM images showed that after application of the SDF/NaF products a crystalline precipitate formed on the dentin surface and partially filled the dentin tubules. The flexural strength (MPa) values were higher in the dentin treated with SDF/NaF + pH-c (Stage 3) compared to the positive control groups (Saforide p=0.002; Cariestop p=0.04; RivaStar p=0.04; NaF p=0.02).

CONCLUSIONS

The application of SDF/NaF affected the physicochemical and mechanical properties of demineralized dentin. According to the results, the use of SFD/NaF had a remineralizing effect on the dentin surface even under acid challenge.

Antimicrobial Efficacy of Silver Diamine Fluoride against Enterococcus faecalis: A Systematic Review of In Vitro Studies

Introduction/Objectives. Enterococcus faecalis has been implicated in infections of treated root canals. Current irrigants and intracanal medicaments cannot eliminate E. faecalis completely from the root canal. Silver diamine fluoride (SDF) prevents caries by promoting remineralization and exerting an antibacterial effect. Studies suggest that SDF may possess antibacterial properties against E. faecalis. The purpose of this review is to systematically and critically analyze the literature, focusing on the use of SDF as an intracanal medicament or irrigant, when compared to other antibacterial agents. Data/Sources. The focused question was "Is the antibacterial effect of SDF against E. faecalis better than other intracanal medicaments and irrigants?" Using the keywords ((silver diamine fluoride) AND (Enterococcus faecalis)) AND ((sodium hypochlorite) OR (NaOCl) OR (chlorhexidine) OR (calcium hydroxide) OR (Ca(OH)₂)), an electronic search was conducted on the following databases: PubMed/MEDLINE, ISI Web of Science, Scopus, EMBASE, and Google Scholar. The clinical trial registers ClinicalTrials.gov and CONTROL were also searched using the same keywords. General characteristics and outcomes were extracted, and quality of the studies was assessed using the Preferred Reporting Items for Laboratory studies in Endodontology (PRILE) guidelines. Study Selection. Six articles (five in vitro studies and one ex vivo study) were included in this systematic review. In the majority of the studies, SDF had equal or better antibacterial efficacy against E. faecalis compared to calcium hydroxide, sodium hypochlorite, and chlorhexidine. However, the majority of the studies did not fulfill several items in the PRILE criteria and had numerous sources of bias. Conclusions. Within the limitations of the systematic review and the studies reviewed, SDF may be effective against E. faecalis and therefore could be used as an intracanal medicament and/or irrigant to prevent reinfections of the root canals and improve the outcomes of endodontic treatment. However, animal and clinical studies should be carried out to determine the efficacy of SDF in endodontics. Trial Registration. The protocol for this review was registered on PROSPERO. Registration number: CRD42021224741.

Potential discolouration of silver diamine fluoride versus silver diamine fluoride/potassium iodide in primary teeth: a randomised clinical study

Aim This study aimed to evaluate the potential discolouration and carious lesion arresting effect of silver diamine fluoride (SDF) and silver diamine fluoride/potassium iodide (SDF/KI) in the treatment of carious primary teeth.Materials and method A total of 30 carious primary canines were randomly assigned to treatment groups where Group I was treated with SDF while Group II was treated with SDF/KI. Caries arrest was assessed based on consistency and stability of lesion size while the discolouration of treated lesions was assessed digitally using a VITA Easyshade spectrophotometer.Results Both treatments demonstrated 100% efficacy in arresting active caries lesions. Regarding discolouration, the total colour difference represented by delta E (ΔE) was 16.45 ± 5.69 for Group I compared to 9.54 ± 3.09 for Group II immediately post-operative, with a statistically significant difference (p = 0.003). Both groups showed similar values at 1, 3, 6 and 12 months after the treatment, with no statistically significant difference. No incidence of serious adverse effects related to either treatment and the majority of parents/guardians were satisfied with both treatments compromising their child's aesthetic appearance.Conclusions Both SDF and SDF/KI are effective in arresting carious lesions in primary teeth but in terms of the discolouration potential, the use of KI significantly reduced the discolouration caused by SDF immediately post-operatively. Unfortunately, marked discolouration was recorded in the subsequent follow-up visits, compromising the aesthetic outcome.

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.

Comparison of Cariostatic and Remineralizing Potential of Two Commercial Silver Diamine Fluoride Preparations using Confocal Laser Microscopy and EDX-SEM Spectroscopy: An In Vitro study

Aim

To investigate the cariostatic and remineralizing effect of two commercial silver diamine fluoride (SDF) preparations on enamel and dentinal caries using a bacterial plaque model.

Materials and methods

A total of 32 extracted primary molars were divided into two groups (n = 16), group I (FAgamin), and group II (SDF). Plaque bacterial model was used to induce caries on enamel and dentin. Preoperative evaluation of samples was done using confocal laser microscopy (CLSM) and energy-dispersive X-ray spectroscopy-scanning electron microscope (EDX-SEM). All samples were treated with test materials and evaluated for postoperative remineralization quantification.

Results

Energy-dispersive X-ray spectroscopy (EDX) revealed that mean preoperative levels (in weight %) of silver (Ag) and fluoride (F2) in carious enamel lesions were 0.0 and 0.0, which increased postoperatively to 11.40 and 31.05 for FAgamin and 13.61 and 31.87 for SDF, respectively. For dentinal caries, EDX revealed mean preoperative levels (in weight %) of Ag and F2 were 0.0 and 0.0, which increased to 11.47 and 48.71 for FAgamin and 10.16 and 47.82 for SDF, respectively postoperatively. Both the groups showed evident demineralization with exposed collagen under SEM. The mean value of enamel lesion depth for the group I and II were 38.64 and 39.30 µm, that reduced to 28.02 and 28.70 µm while for dentinal caries, the mean depth from 38.05 and 38.29 µm that reduced significantly to 28.96 and 30.10 µm, respectively (p < 0.001). Caries depth declined significantly after the application of both FAgamin and SDF (p < 0.001).

Conclusion

FAgamin and SDF show similar cariostatic and remineralization potential for dental caries. The bacterial plaque model used in this study is an efficient method to induce artificial carious lesions in teeth.

Clinical significance

A comparative evaluation of these two cariostatic and remineralizing agents will aid in identifying the efficacy of both commercial products in treating initial caries lesions in an effective noninvasive and child-friendly manner.

How to cite this article

Kale YJ, Misal S, Dadpe MV, et al. Comparison of Cariostatic and Remineralizing Potential of Two Commercial Silver Diamine Fluoride Preparations using Confocal Laser Microscopy and EDX-SEM Spectroscopy: An In Vitro study. Int J Clin Pediatr Dent 2022;15(6):643-651.

General and paediatric dentists' knowledge, attitude and practises regarding the use of Silver Diammine Fluoride for the management of dental caries: a national survey in the Netherlands

Background

Silver Diammine Fluoride (SDF) is a topical medication used to arrest cavitated carious lesions non-invasively. The primary aim was to investigate, and analyse the relationships between; knowledge, attitudes and practises (including barriers and facilitators) for SDF use in the management of dental caries by general dental practitioners (GDPs) and paediatric dentists (PDs) in the Netherlands. A secondary aim was to explore any differences in these, between these groups.

Methods

A randomly selected sample of 600 Dutch GDPs (out of 9,502 respectively) and all 57 registered Dutch PDs were invited to participate in this cross-sectional survey, consisting of four sections: (1) participant characteristics, (2) knowledge (through responses to summative questions), (3) attitudes (through statement agreement using 5-point Likert scale), and (4) practises, use, barriers and facilitators (through multiple choice questions).

Results

The response rates were: GDPs 23% (n = 140) and PDs 47% (n = 27). Knowledge: out of 15 questions to test understanding of SDF, the mean number of correct answers were GDPs 6.7; standard deviation (SD) 2.6 and PDs 7.4, SD 2.2 with no significant difference. The mean overall attitude score showed positive attitudes towards SDF use for both groups. Compared to GDPs, PDs were more likely to use SDF (p < 0.001) and expected to increase their use (p = 0.037). The main barrier for users was parental acceptance (47%) and for non-users it was lack of knowledge (60%). The main facilitator for both users and non-users was gaining knowledge through courses and workshops, followed by written information leaflets about SDF for parents.

Conclusion

Less than half of the knowledge questions about SDF were answered correctly. Despite low knowledge, attitude towards SDF use was positive. Practitioners believed that its use would be facilitated by professionals having more accessible information and training and by the availability of parent information leaflets. Furthermore, SDF is used more frequently by PDs than GDPs.

Fluoride and silver ion concentrations and pH in silver diamine fluoride solutions from Argentina

The aim of this study was to measure the fluoride (F) and silver (Ag) ion concentration and the pH, over time, of 2 solutions of 38% silver diamine fluoride (SDF) produced in Argentina. The brand Fluorsilver® was established as Group 1 (G1) (Densell), and the brand FAgamin® (Tedequim) as Group 2 (G2), each with two different lots. The following were determined at time 0 (t0) and 30 days after opening (t30): a) fluoride concentration (w/v) by visible spectrophotometry b) Ag content (w/v) by atomic absorption spectrophotometry c) pH. Results: The data in the freshly opened bottles were for G1 lot1/lot2: a) 0.96/1, b) 8.3/7.8, c).11.5/11.3; G2 lot1/lot2: a) 11.5/9.9, b) 39/39, c) 7/6,9; and after 30 days, G1 lot1/lot2: a) 0.85/0.81, b) 7.2/8.2, c) 11.3/11.6; G2 lot1/lot2: a) 9.35/8.43, b) 38/38, c) 7.6/7.6. Conclusion In relation to the expected values (5.0-5.9% fluoride and 24.4-28.8% silver), the average concentration of fluoride and silver ions was lower for G1, but higher for G2. The pH was alkaline for G1 and neutral for G2. Over the 30 days, the content of fluoride and silver tended to decrease.

Color changes and shear bond strength to simulated caries lesions treated with a novel solution of 20% silver nanoclusters in polymethacrylic acid

The aims of the study were: (1) To compare the staining effect on demineralized dentin simulating caries between silver nanoclusters (AgNCls) synthesized using polymethacrylic acid (PMAA) and silver diammine fluoride (SDF), and (2) to measure the shear bond strength (SBS) of a glass ionomer cement (GIC) to simulated caries lesions with and without the application of AgNCls/PMAA or SDF. Dentine blocks 4 mm thick from twenty-four non-carious third molars were sectioned and coated with nail varnish (Revlon, New York, USA). Simulated caries lesions on occlusal dentin surfaces were created (66 h in 0.05 M acetate buffer 2.2 mM calcium/phosphate pH 5.0). Specimens were divided into groups and treated with (n = 8): (A) 20% AgNCls/PMAA; (B) SDF 38% (Fagamin, Tedequim, Córdoba, Argentina); or (C) without treatment. AgNCls/PMAA or SDF were applied on the exposed surfaces with a microbrush for 10 s. Samples were incubated for 24 h at 37 °C at 100% relative humidity. Surface color was measured according to the CIE-L*a*b* system before and after demineralization (R0 and R1), 24 h and one week after treatment (R2 and R3), using a spectrophotometer (CM-600D Konica Minolta Sesing Inc., Japan). Groups A and B received an extra application of AgNCls/PMAA or SDF before a conventional GIC (Fuji IX-Gold Label, GC Corp, Tokyo, Japan) was bonded using a mold, 4 mm diameter × 3 mm high. For SBS, a Universal Testing Machine (Digimess RS-8000-5, China)—crosshead speed of 1 mm/min—was used. Statistical analysis was performed using ANOVA, Student-t and Scheffe-test at a significance of p < 0.05. Group A presented a stable color p = 0.24 between R1-R2 and R1-R3 in contrast to significant color changes in Group B (p = 0.02). SBS was higher (p < 0.01) in Group A (10.4 ± 2.7 MPa) compared to Groups B (3.3 ± 1.3 MPa) and C (4.0 ± 0.4 MPa), where no differences between the latter groups were observed (p = 0.77). Results of this preliminary study demonstrated that 20% AgNCls/PMAA did not stain simulated carious dentin and improved SBS of the GIC. The relevance of this study relies on the development of a therapeutic system to potentially arrest caries lesions without staining.

Effectiveness of Silver Diamine Fluoride in Arresting Caries in Primary and Early Mixed Dentition: A Systematic Review

Dental caries is a painful condition that could lead to nutritional problems which affects the overall health of the child, as well it is expensive to treat. The effectiveness of silver diamine fluoride (SDF) in primary and early mixed dentition is systematically reviewed in this study. This systematic review utilized the Preferred Reporting Items for Systematic reviews and Meta- Analysis statement (PRISMA, 2020). A literature search conducted using the common electronic databases (from 2010–2021). Based on the inclusion and exclusion criteria, ten randomized clinical trials (RCT) have met the inclusion criteria and were considered for the qualitative assessment. Critical appraisal of these studies was done. This systematic review found that using SDF is a successful and effective method in arresting dentin carious process in the primary teeth and first permanent molars in children. Additionally, when compared to the commonly used topical fluoride products and materials, SDF showed to have better cariostatic effect. However, these findings must be cautiously viewed since more research is required to support them.

Matrix Metalloproteinases in Dental and Periodontal Tissues and Their Current Inhibitors: Developmental, Degradational and Pathological Aspects

Objectives: This review article aims to describe some of the roles of Matrix metalloproteinases (MMPs) in enamel, dentine, dental caries, hybrid layer degradation, pulp and periodontal tissues, throwing light on their current inhibitors. The article addresses the potential of MMPs to serve as biomarkers with diagnostic and therapeutic value. Design: The sections of this review discuss MMPs’ involvement in developmental, remodeling, degradational and turnover aspects of dental and periodontal tissues as well as their signals in the pathogenesis, progress of different lesions and wound healing of these tissues. The literature was searched for original research articles, review articles and theses. The literature search was conducted in PubMed and MEDLINE for articles published in the last 20 years. Results: 119 published papers, two textbooks and two doctoral theses were selected for preparing the current review. Conclusions: MMPs are significant proteases, of evident contribution in dental and periapical tissue development, health and disease processes, with promising potential for use as diagnostic and prognostic disease biomarkers. Continuing understanding of their role in pathogenesis and progress of different dental, periapical and periodontal lesions, as well as in dentine-pulp wound healing could be a keystone to future diagnostic and therapeutic regimens.

Characterization of silver diamine fluoride cytotoxicity using microfluidic tooth-on-a-chip and gingival equivalents

OBJECTIVE

This study aims to characterize the cytotoxicity potential of silver diamine fluoride (SDF) on dental pulp stem cells (DPSC) and gingival equivalents.

METHODS

DPSC cultured on 96-well plates was exposed directly to SDF (0.0001-0.01%) and cell viability (IC₅₀) quantified. Effect of SDF on DPSC viability under flow (with dentin barrier) conditions was evaluated using a custom-designed microfluidic "tooth-on-a-chip". Permeability of dentin discs (0.5-1.5 mm thickness) was evaluated using lucifer yellow permeation assay. Dentin discs were treated with 38% SDF (up to 3 h), and cell viability (live/dead assay) of the DPSC cultured in the inlet (unexposed) and outlet (exposed) regions of the pulp channel was evaluated. To assess the mucosal corrosion potential, gingival equivalents were treated with 38% SDF for 3 or 60 min (OECD test guideline 431) and characterized by MTT assay and histomorphometric analysis.

RESULTS

DPSC exposed directly to SDF showed a dose-dependent reduction in cell viability (IC₅₀: 0.001%). Inlet channels (internal control) of the tooth-on-a-chip exposed to PBS and SDF-exposed dentin discs showed> 85% DPSC viability. In contrast, the outlet channels of SDF-exposed dentin discs showed a decreased viability of< 31% and 0% (1.5 and ≤1.0 mm thick dentin disc, respectively) (p < 0.01). The gingiva equivalents treated with SDF for 3 and 60 min demonstrated decreased epithelial integrity, loss of intercellular cohesion and corneal layer detachment with significant reduction in intact epithelial thickness (p < 0.05).

SIGNIFICANCE

SDF penetrated the dentin (≤1 mm thick) inducing significant death of the pulp cells. SDF also disrupted gingival epithelial integrity resulting in mucosal corrosion.

Does silver diammine fluoride concentration influence on bonding to carious dentinal lesions in primary teeth?

PURPOSE

This in vitro study evaluated the microshear bond strength (μSBS) of a universal adhesive after silver diammine fluoride (SDF) application at different concentrations on carious dentinal lesions in primary teeth.

METHODS

Flat dentin carious-induced surfaces from 40 primary molars were randomly assigned to four experimental groups: without SDF treatment (control), 12% SDF, 30% SDF, or 38% SDF application. After 14 days of storage in artificial saliva at 37 °C, a universal adhesive system (Scotchbond Universal, 3 M ESPE) was applied in the etch-and-rinse mode and resin composite cylinders were built (0.72 mm²). After 24 h of water storage, the μSBS test was performed and the failure mode was determined. Data were analysed using one-way ANOVA and Tukey's post hoc tests (α = 0.05).

RESULTS

The application of 38% SDF resulted in higher μSBS mean than control and use of 12% SDF (p = 0.006). No significant differences were observed among control, 12% SDF, and 30% SDF. All specimens tested showed adhesive/mixed failure.

CONCLUSION

The use of SDF does not jeopardise the bonding of a universal adhesive applied in the etch-and-rinse mode to carious dentinal lesions in primary teeth, irrespective of the product concentration.

Effect of strontium-doped bioactive glass-ceramic containing toothpaste on prevention of artificial dentine caries formation: an in vitro study

Backgroud

Root caries in aging population was prevalent worldwide. Due to the absence of enamel and specific structure of dentine, bacteria are able to penetrate further into dentine at an earlier stage of lesion development. The aim of this study was to investigate the effect of adding of a strontium-doped bioactive glass-ceramic (HX-BGC) to a fluoride-free toothpaste on prevention of formation of artificial dentine caries.

Methods

Thirty-six human tooth specimens were allocated to three groups (n = 12 per group). Group 1 treated with slurry containing a fluoride-free toothpaste and 5% HX-BGC, Group 2 was treated with fluoride-free toothpaste slurry, and Group 3 received deionized water as a negative control. The specimens were subjected to four cycles (15 h demineralization and 8 h remineralization for one cycle) of biochemical cycling. A mixed suspension of five bacteria species (Streptococcus mutans, Streptococcus sobrinus, Lactobacillus acidophilus, Lactobacillus rhamnosus, and Actinomyces naeslundii) were prepared in brain heart infusion broth with 5% sucrose and used as acidic challenge in biochemical cycling. Subsequently, surface morphology of the dentine lesion was assessed by scanning electron microscopy, while the lesion depths and mineral loss were assessed by micro-computed tomography.

Results

The mean lesion depths in dentine in Groups 1 to 3 were 87.79 ± 16.99 μm, 101.06 ± 10.04 μm and 113.60 ± 16.36 μm, respectively (p = 0.002). The mean amounts of mineral loss in Groups 1 to 3 were 0.82 ± 0.10 g/cm³, 0.89 ± 0.09 g/cm³ and 0.96 ± 0.11 g/cm³, respectively (p = 0.016). No obvious differences in the surface morphology were seen among the groups.

Conclusion

Addition of strontium-doped bioactive glass-ceramic to fluoride-free toothpaste has potential to reduce formation of dentine lesions.

Functional role of inorganic trace elements in dentin apatite tissue-part III: Se, F, Ag, and B

Dentin hydroxyapatite possesses a unique versatile structure which allows it to undergo ionic substitutions. Trace elements play pivotal roles within the oral cavity, especially in dentin apatite tissue. Therefore, it is critical to explore the role of these elements in dentin apatite structure. The roles of other inorganic elements in dentin apatite were discussed in part I (Mg, Sr, Zn, and Fe) and part II (Cu, Mn, Si, and Li) of these series. In the last part of the review series, the role of selenium, fluorine, silver, and boron in the regulation of dentin apatite structure and function was discussed. We evaluated how these elements affect the overall size, morphology, and crystallinity of dentin apatite crystals. Moreover, we investigated the importance of these elements in regulating the solubility of dentin apatite. An electronic search was performed on the role of these trace elements in dentin apatite from January 2010 to January 2022. The concentration of selenium in teeth has been explored only recently, particularly its incorporation into dentin apatite. Silver nanomaterials inhibit the growth of cariogenic microorganisms as well as arrest the degradation of collagen. Fluorine was found to have important roles in dentin remineralization and dentinal tubule occlusion, making it widely used for hydroxyapatite doping. Boron is critical for mineralized tissues like bone, dentin, and enamel, but its exact role in dentin apatite is unknown. Therefore, understanding the impact of these elements on dentin apatite is potentially transformative, as it may help to fill a significant knowledge gap in teeth mechanics.