Laboratory evaluation of the potential masking of color changes produced by silver diamine fluoride in primary molars

A colorimetric and fluorescent probe of lignocellulose nanofiber composite modified with Rhodamine 6G derivative for reversible, selective and sensitive detection of metal ions in wastewater

Heavy metal ions have extremely high toxicity. As the top of food chain, human beings certainly will accumulate them by ingesting food and participating other activities, which eventually result in the damage to our health. Therefore, it is very meaningful and necessary to design a simple, portable, stable and efficient material for heavy metal ions detection. Based on the spirolactam Rhodamine 6G (SRh6G) fluorescent probe, we prepared two types of nanocomposite materials (membrane and aerogel) by vacuum filtration and freeze-drying methods with lignocellulose nanofiber (CNF) as a carrier, polyvinyl alcohol (PVA) and glutaraldehyde (GA) as the cross-linkers. Then the microstructure, chemical composition, wetting property, fluorescence intensity and selectivity of as-prepared SRh6G/PVA/CNF would be characterized and analyzed. Results showed that SRh6G/PVA/CNF nanocomposites would turn red in color under strong acidic environment and produced orange fluorescence under ultraviolet light. Besides, they were also to detect Al3+, Cu2+, Hg2+, Fe3+ and Ag+ through color and fluorescence variations. We had further tested its sensitivity, selectivity, adsorption, fluorescence limits of detection (LOD) to Fe3+ and Cu2+. The test towards real water samples (hospital wastewater, Songhua River and tap water) proved that SRh6G/PVA/CNF nanocomposites could detect the polluted water with low concentrations of Fe3+ and Cu2+. In addition, SRh6G/PVA/CNF nanocomposites have excellent mechanical property, repeatability, superhydrophilicity and underwater superoleophobicity, which may offer a theoretical reference for the assembly strategy and detection application of cellulose-based fluorescent probe.

The Impact of Silver Diamine Fluoride Only or Simultaneously With Potassium Iodide Treatment on the Bond Durability of Resin Composite Material on Primary Teeth

We aim to evaluate the bond strength between resin composite and primary demineralized dentin, pretreated with silver diamine fluoride (SDF) and simultaneous SDF with potassium iodide (KI) after thermal aging. In this in vitro study, human carious-free primary molars were randomly assigned into three groups and prepared by exposing the superficial dentin. The primary dentin of each molar was demineralized. The first group (the control) received saline treatment before bond application. SDF was pretreated for the second group, whereas SDF and KI were used for the third. After that, the pretreated dentin was immediately built with resin composite bonded with a universal adhesive and kept wet for 24 hours. Then, the pretreated molars were prepared into beam specimens for microtensile bond strength (µTBS), 16 for each group, and subjected to thermal aging. Lastly, they were tested using a universal testing machine, and the resulting data were analyzed using one-way analysis of variance (ANOVA) followed by Tukey's post hoc test. It was found that the SDF-KI group had a significant difference with both the control and SDF groups (p < 0.05), while the control and SDF groups showed no significant differences (p = 0.310). The SDF-KI group had the highest mean value of 11.73 ± 4.39 megapascal (MPa). In contrast, the control group had the lowest mean value of 9.31 ± 3.41 MPa. Post hoc pairwise comparison results showed that SDF-KI pretreatment had a significantly higher strength value than the control and SDF groups. Pretreatment of demineralized primary dentin with SDF-KI does not negatively affect the immediate loading of resin composite. However, under the limitation of this study, KI application after SDF pretreatment is recommended to enhance the bond's durability of resin composite to demineralized dentin.

Acceptance of silver diamine fluoride use in community dwelling older adults, nursing home residents, and caregivers

OBJECTIVES

To compare the level of acceptance of silver diamine fluoride (SDF) treatment between different functional groups of older adults aged 65-years-old and above.

METHODS

Three groups were recruited representing functionally-independent ("Community dwelling"), frail ("Nursing home"), and functionally-dependent older adults ("Caregiver": proxy respondent involved in caring for an older adult of all functional levels). Participants viewed a video on SDF and an interviewer-led questionnaire collected demographics, dental experience and perception on SDF use.

RESULTS

The study recruited 201 participants (100 "Community dwelling", 51 "Nursing home", 50 "Caregiver"). Overall, 73 % of participants were accepting of SDF treatment. Those in the "Community dwelling" group were most accepting (85 %), followed by the "Nursing home" group (61 %) and "Caregiver" group (60 %) (p<0.001). Participants were more accepting of SDF use on posterior (73 %) compared to anterior teeth (46 %). They were more accepting when SDF was presented as a treatment to avoid infection and pain (87 %), and general anesthesia (78 %). In a regression analysis, "Nursing home" and "Caregiver" participants were three times less likely to accept SDF (OR 0.27 [95 % CI: 0.13 to 0.60], and OR 0.27 [95 % CI: 0.12 to 0.58] respectively) compared to "Community dwelling" participants. After adjusting for other factors, only the "Caregiver" group remained significant (Adjusted OR 0.32 [95 % CI: 0.13 to 0.78]).

CONCLUSIONS

Older adults were accepting of SDF and this treatment modality has the potential to be a routine treatment option in dental caries management in this population. However, this was less certain among frail and functionally dependent older adults.

CLINICAL SIGNIFICANCE

An SDF program to manage caries is likely to be well-received by functionally-independent older adults. However, the acceptance among frail and functionally-dependent older adults were lower even though SDF is mostly likely to benefit these populations. There is a need to investigate this relatively lower levels of acceptance.

In vitro comparative evaluation of physical and chemical properties of surface enamel after using APF and SDF with or without laser activation

PURPOSE

To evaluate and compare the changes in physical and chemical properties of the enamel surface after application of Silver Diamine Fluoride (SDF), Acidulated Phosphate Fluoride (APF), LASER activated SDF and LASER activated APF.

METHODS

Sample consisted of 72 freshly extracted healthy human premolar teeth, extracted for orthodontic purpose, free from caries, fracture or any anomalies. The selected samples were randomly divided into four groups (n = 18): Group 1 (SDF); Group 2 (APF); Group 3 (LASER activated SDF) and Group 4 (LASER activated APF). All samples were evaluated for values of DIAGNOdent at baseline, after demineralisation and after remineralisation. They were further divided and assessed for colour changes, surface alterations and fluoride content of surface enamel using Spectrophotometer, Scanning Electron Microscopy and Energy Dispersive X-ray Spectrometry respectively. The statistical analysis was done using One-Way ANOVA, Tukey's HSD test, Mann-Whitney U test and Kruskal-Wallis Test.

RESULTS

Highest remineralising potential and maximum colour changes of surface enamel was exhibited by Group 3. Scanning Electron Micrographs of Group 3 and Group 4 exhibited regular globular structures of enamel whereas Group 1 and Group 2 showed irregular globular surface of the enamel at 2000× and 5000× magnification. Maximum fluoride uptake on the surface enamel was seen in Group 4 followed by Group 3.

CONCLUSION

Use of LASER activated topical fluorides helps to achieve superior caries prevention. LASER activated APF can be used as an aesthetic alternative to SDF, as LASER activated APF showed higher uptake of fluoride on the enamel surface without discoloration effect.

Inhibition of Silver Diamine Fluoride-induced Tooth Discoloration by Using Natural Antioxidant: In Vitro Study

AIM

Silver diamine fluoride (SDF) is a well-known caries preventive aid capable of arresting carious lesions and preventing secondary caries formation. Despite having the caries prevention potential, the clinical use of SDF is limited due to the tooth discoloration caused by SDF. The objective of this study was to evaluate the efficiency of natural antioxidants to inhibit SDF-induced tooth discoloration.

MATERIALS AND METHODS

A total of 32 bovine teeth were polished to create a 6 mm circular window on the middle 1/3 (for enamel) or on the cervical 1/3 (for dentin) of the labial surface. Specimens were treated either with SDF alone or SDF followed by ascorbic acid (AA)/alpha lipoic acid (ALA)/7th generation bonding materials. The color parameters Lightness (L*), Chroma (C*), and Hue (H*) of the tooth window were measured at pretreatment, 1-hour, 1-week, and 1-month posttreatment using a digital color chromometer.

RESULTS

Repeated measure ANOVA showed a significant tooth color alteration at 1-hour posttreatment. The L* and H* values dropped and C* value elevated significantly in 1-hour posttreatment measurement. All experimental groups showed significant tooth color alteration after treatment (p < 0.05) and were unable to reverse the discoloration even after 1-month period except the ALA group which did not show any significant (p > 0.05) color alteration compared with the pretreatment value.

CONCLUSIONS

Within the limitation of the in vitro model and according to the results of this study, it can be concluded that ALA has the potential to prevent SDF-induced tooth discoloration; however, AA was unable to prevent the discoloration.

CLINICAL SIGNIFICANCE

SDF induces discoloration of enamel and dentin can be reversed by applying Alpha lipoic acid immediacy after SDF application.

Influence of salivary acquired pellicle on colour changes and minerals content of dentine after application of silver diamine fluoride followed by potassium iodide

PURPOSE

This study evaluated whether the presence of the salivary acquired pellicle (AP) had any effect on the dentin's darkening and on the caries arresting effect after the use of SDF + KI, in a cariogenic challenge.

METHODS

Human dentin specimens were standardised, submitted to artificial caries lesion formation, and divided into five groups (n = 20): C: control group-no treatment, SDF: 38% SDF, APSDF: SDF 38% and AP, KISDF: 38% SDF and KI, and APKISDF: 38% SDF, KI and AP, that were submitted to pH cycling. Colour evaluation (CIE L*a*b* system) and surface hardness were performed before and after the treatments/pH cycling.

RESULTS

SDF and APSDF groups showed no difference in colour. KISDF and APKISDF groups showed significantly different colours than the groups without KI. SDF, APSDF, and APKISDF groups had less mineral loss than C and KISDF. SDF, APSDF, and APKISDF revealed significantly greater mineral recovery, compared to KISDF and C.

CONCLUSION

The AP did not influence the dentin´s colour after SDF + KI, but had a protective role in modulating the dentin´s mineral gain/loss. KI used after SDF decreased the dentin´s darkening, and did not interfere with the dentin de/remineralization process.

Annual review of selected scientific literature: A report of the Committee on Scientific Investigation of the American Academy of Restorative Dentistry

The Scientific Investigation Committee of the American Academy of Restorative Dentistry offers this review of the 2021 dental literature in restorative dentistry to inform busy dentists regarding noteworthy scientific and clinical progress over the past year. Each member of the committee brings discipline-specific expertise to coverage of this broad topical area. Specific subject areas addressed, in order of the appearance in this report, include COVID-19 and the dental profession (new); prosthodontics; periodontics, alveolar bone, and peri-implant tissues; implant dentistry; dental materials and therapeutics; occlusion and temporomandibular disorders; sleep-related breathing disorders; oral medicine and oral and maxillofacial surgery; and dental caries and cariology. The authors focused their efforts on reporting information likely to influence daily dental treatment decisions with an emphasis on future trends in dentistry. With the tremendous volume of dentistry and related literature being published daily, this review cannot possibly be comprehensive. Rather, its purpose is to update interested readers and provide important resource material for those interested in pursuing greater details on their own. It remains our intent to assist colleagues in negotiating the extensive volume of important information being published annually. It is our hope that readers find this work useful in successfully managing the patients and dental problems they encounter.

The Effect of Loading Time on Color Stability of Various Restorative Materials Bonded to Silver Diamine Fluoride-Treated Demineralized Dentin

Aim

To investigate the effect of immediate versus one week later loading time on color stability of resin-based composite (RBC), resin-modified glass ionomer cement (RMGIC) and glass ionomer cement (GIC) restorative materials bonded to silver diamine fluoride (SDF)-treated demineralized dentin.

Materials and Methods

Ninety extracted premolars were randomly assigned to the following groups (n = 30 each): group-I (loaded with RBCs), group-II (loaded with RMGIC), and group-III (loaded with GIC). Each group was divided randomly into the following subgroups (n = 10): subgroup-A (control specimens) consisted of sound dentin and the restorative material was immediately loaded; subgroup-B consisted of demineralized dentin, underwent a SDF treatment and the restorative material was immediately loaded; subgroup-C consisted of demineralized dentin, underwent a SDF treatment and the restorative material was loaded 1 week later. The color difference (ΔE) and visual color changes (L*a*b*) of each specimen were calculated using a spectrophotometer. Data were analyzed using one-way ANOVA and post hoc Tukey's tests to compare the ΔE values and a paired t test to compare the mean of L* a* b* coordinates.

Results

The highest color stability was observed for GIC, followed by RMGIC, and the lowest color stability was observed for the RBC group. Significant differences within groups were noted in RBC and RMGIC (p < 0.001). Regarding the loading time of the restorative material, in RBCs, a significantly lower ΔE value was observed in the delayed loading group than in the immediate loading group (p = 0.035). In the RMGIC and GIC groups, there were no significant differences.

Conclusion

Delaying the loading time of the restorative material for 1 week following the application of SDF resulted in greater color stability than that of immediate loading. The caries arresting potential of SDF was revealed by the dark staining, which could be improved with the subsequent delayed restoration.

Peptide-Enabled Nanocomposites Offer Biomimetic Reconstruction of Silver Diamine Fluoride-Treated Dental Tissues

Caries is the most ubiquitous infectious disease of mankind, and early childhood caries (ECC) is the most prevalent chronic disease in children worldwide, with the resulting destruction of the teeth recognized as a global health crisis. Recent the United States Food and Drug Administration (FDA) approval for the use of silver diamine fluoride (SDF) in dentistry offers a safe, accessible, and inexpensive approach to arrest caries progression in children with ECC. However, discoloration, i.e., black staining, of demineralized or cavitated surfaces treated with SDF has limited its widespread use. Targeting SDF-treated tooth surfaces, we developed a biohybrid calcium phosphate nanocomposite interface building upon the self-assembly of synthetic biomimetic peptides. Here, an engineered bifunctional peptide composed of a silver binding peptide (AgBP) is covalently joined to an amelogenin derived peptide (ADP). The AgBP provides anchoring to the SDF-treated tooth tissue, while the ADP promotes rapid formation of a calcium phosphate isomorph nanocomposite mimicking the biomineralization function of the amelogenin protein. Our results demonstrate that the bifunctional peptide was effective in remineralizing the biomineral destroyed by caries on the SDF-treated tooth tissues. The proposed engineered peptide approach offers a biomimetic path for remineralization of the SDF-treated tissues producing a calcium phosphate nanocomposite interface competent to be restored using commonly available adhesive dental composites.