Managing dental caries against the backdrop of COVID-19: approaches to reduce aerosol generation

Parental perceptions and acceptance of silver diamine fluoride staining in Italy

BACKGROUND

Parental perceptions of staining due to silver diamine fluoride (SDF) could affect its utilization in paediatric dentistry. This study represents the second part of a wider project focused on SDF esthetic acceptability among Italian parents.

AIM

To evaluate parental acceptance of SDF staining in Italy and to assess whether the parent's level of acceptance depends on location, child's behavior, or demographic background.

DESIGN

A cross-sectional study was conducted among Italian parents of children attending two university dental clinics. We used a validated Italian version of the questionnaire "Parental Perceptions of Silver Diamine Fluoride Dental Color Changes."

RESULTS

Two hundred and thirty-four parents took part in the survey. Of parents, 65.4% considered the staining on posterior teeth esthetically "acceptable" or "somewhat acceptable," and 19.3% on anterior teeth (p = .001). In a scenario of positive cooperation, 48.5% of parents were "somewhat likely" or "very likely" to choose SDF to treat posterior teeth, and 17.6% on anterior teeth (p = .001). Level of acceptance increased as the difficulty the child would experience to receive conventional treatment increased.

CONCLUSION

Staining on posterior teeth is more acceptable to parents than staining on anterior teeth. Level of acceptance on anterior teeth increases when sedation or general anesthesia is the alternative for the child.

Impact of COVID-19 on Otorhinolaryngologists in Bulgaria: A Survey of Healthcare Professionals

Background The COVID-19 pandemic caused significant global social and economic disruption, highlighting the challenges of emerging infectious diseases. It also pushed modern medicine and healthcare systems to the wall. The mode of transmission of the SARS-CoV-2 infection is by aerosolized upper respiratory tract secretions. The otorhinolaryngology specialty seems to be among the riskiest for contracting airborne infections. This is because of the close face-to-face contact with the patients during routine examinations and many specific procedures. This study aimed to evaluate otolaryngologists' self-assessment of their comparative infection risk and the impact of the COVID-19 pandemic on their clinical practice, financial stability, and psychological well-being. Methodology A national cross-sectional survey was conducted among otorhinolaryngologists in Bulgaria by a research team from the Medical University of Varna. The study assessed infection risk perception, changes in practice, psychological stress, and financial effects. Data were collected via Survs.com and analyzed using descriptive statistics, cross-tabulations, and chi-squared tests, with significance set at 0.05 in Jamovi version 2.3.28. Results Of the 241 invited participants, 120 (49.8%) completed the survey. In total, 61 (50.8%) perceived their infection risk as similar to emergency healthcare workers, while 91 (75.8%) likened their exposure to that of dentists. Workplace exposure was identified as the main infection source by 95 (79.1%), with 71 (59.1%) considering outpatient clinics the highest-risk setting. Financially, 47 (39.1%) reported no income change, 31 (25.8%) experienced reductions, and 42 (35.0%) saw increased earnings. A chi-square test revealed a significant association between financial impact and workplace setting (χ² (3) = 11.68, p = 0.0086). Hospital-based otolaryngologists were more frequently affected by income reductions, with 65 (54.2%) reporting financial losses compared to 22 (18.3%) in outpatient settings. The psychological toll was substantial, with 44 (36.6%) reporting high stress, 34 (28.3%) very high stress, and only 3 (2.5%) stating no effect. Significant associations were found between stress levels and workplace setting (χ² (4) = 12.4, p = 0.015) and work experience (χ² (12) = 22.9, p = 0.029). Conclusions The COVID-19 pandemic profoundly affected otorhinolaryngologists' financial stability, work environments, infection risk perception, and mental health. Hospital-based specialists faced greater financial challenges, while stress levels were significantly linked to workplace setting and experience. These findings highlight critical areas for long-term changes in otorhinolaryngological practice.

Microbiological and Ergonomic Effects of Three Prototypes of a Device to Reduce Aerosol Dispersion in Dental Care During the COVID-19 Pandemic: A Randomized Controlled Clinical Trial

Objectives: This randomized clinical trial evaluated the microbiological efficacy and the ergonomic impact of three prototypes of a device to reduce aerosol dispersion during dental procedures. Methods: Sixty patients undergoing dental care using high-speed turbines and/or ultrasonic tips were randomly assigned to 4 groups (n = 15): CG: control group, with standard personal protective equipment (PPE); G1: PPE + acrylic device (AD) with aspiration; G2: PPE + AD without aspiration; and G3: PPE + polyvinyl chloride device. The device prototypes consisted of a rigid translucent acrylic structure (G1 and G2), or a rigid PVC tube structure surrounded by layers of translucent flexible PVC films (G3), adjusted to the dental chair, involving the patient's head, neck and chest. The main outcome was the microbiological analysis (mean Δ of CFU at 10 different sites), and the secondary outcome was the ergonomic evaluation (questionnaire to dentists and patients). Results: The final sample comprised 59 participants (mean age 38.6 ± 11.4 years, 55.2% male). The overall mean time for dental procedures was 32.4 ± 16.9 min, with no differences between groups (p = 0.348). Microbiological analyses showed that the use of the device significantly reduced contamination in the light reflector (01.46 ± 4.43 ΔCFU in G2 vs. 19.25 ± 36.50 ΔCFU in CG; p = 0.028), apron (09.11 ± 12.05 ΔCFU in G3 vs. 21.14 ± 43.41 ΔCFU in GC; p = 0.044), and face shield (08.80 ± 32.70 ΔCFU in G1 vs. 56.78 ± 76.64 ΔCFU in the GC; p = 0.017). The device was well accepted by patients and increased the dentists' perception of safety and protection (p < 0.001), but significantly decreased ergonomics related to the clinical view, space, agility and access to the patient, and ease of performing procedures (p < 0.001). Conclusions: The tested device can be an additional tool for infection prevention and control in dentistry, not only during the COVID-19 pandemic, but also for the control of future infectious diseases and epidemics.

Exploring the efficacy of in-vitro low-temperature plasma treatment on single and multispecies dental cariogenic biofilms

The primary aim of this study was to investigate the impact of treatment with low-temperature plasma (LTP) for varying exposure durations on a multispecies cariogenic biofilm comprising C. albicans, L. casei, and S. mutans, as well as on single-species biofilms of L. casei and C. albicans, cultured on hydroxyapatite discs. Biofilms were treated with LTP-argon at a 10 mm distance for 30 s, 60 s, and 120 s. Chlorhexidine solution (0.12%) and NaCl (0.89%) were used as positive (PC) and negative controls (NC), respectively. Argon flow only was also used as gas flow control (F). Colony-forming units (CFU) recovery and confocal laser scanning microscopy (CLSM) were used to analyze biofilm viability. LTP starting at 30 s of application significantly reduced the viability of multispecies biofilms by more than 2 log10 in all treated samples (p < 0.0001). For single-species biofilms, L. casei showed a significant reduction compared to PC and NC of over 1 log10 at all exposure times (p < 0.0001). In the case of C. albicans biofilms, LTP treatment compared to PC and NC resulted in a significant decrease in bacterial counts when applied for 60 and 120 s (1.55 and 1.90 log10 CFU/mL, respectively) (p < 0.0001). A significant effect (p ≤ 0.05) of LTP in single-species biofilms was observed to start at 60 s of LTP application compared to F, suggesting a time-dependent effect of LTP for the single-species biofilms of C. albicans and L. casei. LTP is a potential mechanism in treating dental caries by being an effective anti-biofilm therapy of both single and multispecies cariogenic biofilms.

Effects of Acidic Challenge on Demineralized Root Surface Treated with Silver Diamine Fluoride and Potassium Iodide

BACKGROUND

The aim of the study was to assess the protective effect of applying potassium iodide (KI) over silver diamine fluoride (SDF) on demineralized root dentin in the case of a sustained acidogenic attack.

METHODS

Forty caries-free third molars were used in the study. A diamond disc was used to separate the roots and the tooth crowns from the roots. Each root fragment was randomly distributed in one of the four study groups: C-samples were not demineralized; DD-demineralized samples; RS1-demineralized samples covered with SDF+KI (RS-Riva Star product, SDI limited, Bayswater, Australia); RS2-demineralized samples covered with SDF+KI and submersed to another acidic challenge for 3 days. SEM and EDX were used for the morphological and elemental analysis. Vickers hardness assessment was performed using a tribometer CETR UMT-2 (Bruker Corporation, Berlin, Germany). One-way ANOVA and post hoc Bonferroni tests were used for the statistical analysis with a significance level of p < 0.05.

RESULTS

Morphological and elemental changes were observed on the surface of the study samples. Significant differences were observed between the recorded hardness values of groups C and DD (p = 0.005), C and RS2 (p = 0.002), DD and RS1 (p = 0.011); RS1 and RS2 (p = 0.004).

CONCLUSIONS

The application of SDF and KI (Riva Star product) on root dentin caries resulted in the formation of a heterogeneous outer layer that sealed the dentin and increased the microhardness of the treated surface. In the conditions of the present study, this layer did not provide enough protection for root dentin exposed to continuous attacks.

Characterization of Ag-Ion Releasing Zeolite Filled 3D Printed Resins

There has been profound growth in the use of 3D printed materials in dentistry in general, including orthodontics. The opportunity to impart antimicrobial properties to 3D printed parts from existing resins requires the capability of forming a stable colloid incorporating antimicrobial fillers. The objective of this research was to characterize a colloid consisting of a 3D printable resin mixed with Ag-ion releasing zeolites and fumed silica to create 3D printed parts with antiviral properties. The final composite was tested for antiviral properties against SARS-CoV-2 and HIV-1. Antiviral activity was measured in terms of the half-life of SARS-CoV-2 and HIV-1 on the composite surface. The inclusion of the zeolite did not interfere with the kinetics measured on the surface of the ATR crystal. While the depth of cure, measured following ISO4049 guidelines, was reduced from 3.8 mm to 1.4 mm in 5 s, this greatly exceeded the resolution required for 3D printing. The colloid was stable for at least 6 months and the rheological behavior was dependent upon the fumed silica loading. The inclusion of zeolites and fumed silica significantly increased the flexural strength of the composite as measured by a 3 point bend test. The composite released approximately 2500 μg/L of silver ion per gram of composite as determined by potentiometry. There was a significant reduction of the average half-life of SARS-CoV-2 (1.9 fold) and HIV-1 (2.7 fold) on the surface of the composite. The inclusion of Ag-ion releasing zeolites into 3D-printable resin can result in stable colloids that generate composites with improved mechanical properties and antiviral properties.

COVID-19 as an opportunity for minimally-invasive dentistry: a national cross-sectional survey

Background

During the COVID19 pandemic, the Latvian government issued first absolute restrictions (elective treatments prohibited, only emergency care) and later relative restrictions (preference for non-aerosol-generating procedures (AGP) and emergency care) on dental care. This study aims to assess the impact of these restrictions on the decision made by Latvian dentists about caries treatment.

Methods

A Survey-based cross-sectional study was used. A minimum sample size of 174 dentists was estimated for national representativeness (N = 1524). The questionnaire was developed by experts and sent three times via email to Latvian dentists from July to September 2020 and was also delivered in printed form at two national conferences in September and October 2020. Descriptive statistics were calculated.

Results

We received 373 completed questionnaires, with a total response rate of 24.5%. Under the recommendation to reduce AGP for the treatment of uncomplicated caries, 10% of the dentists stated that they would stop attending, 54% would only attend emergencies, and 36% would attend as usual. Under prohibition, the percentages are 15%, 74%, and 11%, respectively. Regarding the type of treatment, more than 75% would opt to proceed with selective caries removal for both primary and permanent teeth and 10% for extraction.

Conclusion

Latvian dentists are willing to treat patients with caries during the pandemic and state that they prefer to use non- or minimally invasive and less aerosol-generating methods for caries treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-022-02432-7.

A Bibliometric Analysis (2010-2020) of the Dental Scientific Literature on Chemo-Mechanical Methods of Caries Removal Using Carisolv and BRIX3000

Reports in the literature have proposed and analyzed several minimally invasive techniques for caries removal in recent decades. In light of recent events surrounding the ongoing epidemiological context, concerns have been raised regarding the generation of aerosols during dental procedures. The aim of our research was to provide an overview of the scientific literature on the topic of chemo-mechanical caries removal (CMCR) methods, focusing on two products (Carisolv, BRIX3000), commercially available in Europe. A bibliometric analysis was used to investigate the scientific articles included in Web of Science (WoS) Core Collection database, published from January 2010 to December 2020. We analyzed the co-occurrence of all keywords (Author Keywords and the KeyWords Plus section), co-authorship and co-citation, using the free software VOSviewer. Our bibliometric analysis revealed a worldwide interest in the subject of chemo-mechanical methods of caries removal, which has transcended the area of pediatric dentistry. The analyzed studies have been conducted mainly in high-income countries that have developed sanitary policies regarding prevention and early treatment of carious lesions as a health priority.

The Cytocompatibility of Silver Diamine Fluoride on Mesenchymal Stromal Cells from Human Exfoliated Deciduous Teeth: An In Vitro Study

Silver diamine fluoride (SDF) has been used for many years for the treatment of caries, and minimally invasive dentistry concepts have made it popular again. The fact that its application does not require the administration of anesthesia makes its use in children more desirable. The aim of this study was to determine the cytotoxicity of two new commercial SDF products: Riva Star (SDI Dental Limited) and e-SDF (Kids-e-Dental) on mesenchymal stromal cells from human exfoliated deciduous teeth (SHEDs). SHEDs were exposed to SDF products at different concentrations (0.1%, 0.01% and 0.005%). Then different assays were performed to evaluate their cytocompatibility on SHEDs: IC50, MTT, cell migration (wound healing), cell cytoskeleton staining, cell apoptosis, generation of intracellular reactive oxygen species (ROS), and ion chromatography. Statistical analyses were performed using one-way ANOVA and Tukey’s post hoc test (p < 0.05). Riva Star Step 2 showed the same cell metabolic activity when compared to the control condition at any time and concentration. Meanwhile, e-SDF displayed high cytotoxicity at any time and any concentration (*** p < 0.001), whereas Riva Star Step 1 displayed high cytotoxicity at any time at 0.1% and 0.01% (*** p < 0.001). Only e-SDF showed a statistically significant decreased cell migration rate (*** p < 0.001) at all times and in all concentrations. At 0.1%, e-SDF and Riva Star Step 1 only showed 4.37% and 4.47% of viable cells, respectively. These results suggest that Riva Star has better in vitro cytocompatibility on SHEDs than does e-SDF. Riva Star Step 1 was found to be as cytotoxic as e-SDF, but it had better biological properties when mixed with Riva Star Step 2. Our findings suggest that Riva Star is more suitable when used in deciduous teeth due to its lower cytotoxicity compared to e-SDF.

M. Is Non-Restorative Cavity Treatment a Practical Choice in Primary Teeth?

For years, “extension for prevention” was considered as the standard protocol for the restoration of caries. With advances in the field of cariology regarding the biofilm and improvement in materials, this perspective is being challenged. This is being challenged by more biological and less-invasive approaches, where the emphasis is on biofilm alteration to arrest carious lesions. This minimally invasive intervention is based on the concept that biofilm overlying the carious lesion is a driving force for the carious process and not the bacteria present in the infected dentin. Hence, daily removal or disruption of this biofilm will slow down the carious process or bring it to halt.

One such approach is non-restorative cavity treatment, where no caries is removed but lesions are made self-cleansable that allows it to be brushed by the parent or the child. This wholesome approach targets the disease at a causal level.

This review of literature describes the various advantages and limitations of this technique and the practicability of its use in pediatric patients during the pandemic COVID-19.

Coronavirus disease (COVID-19) transmission through aerosols in restorative and endodontic practice: Strategies for prevention

Rapid spread of coronavirus disease 2019 (COVID-19) in several countries of the world has created a state of public health emergency. COVID-19 is principally a respiratory disease, and the virus is present in respiratory secretions. Oral health-care professionals are susceptible to being infected with the disease since they work in close proximity to patient's face and oral cavity for long period of time. Restorative dentists and endodontists play a significant role in delivering "urgent" or "emergency" dental care to patients. Occupational Safety and Health Administration has categorized dentists performing aerosol-generating treatment procedures at "very high exposure risk" whereas the dentists not performing aerosol-generating procedures at "high exposure risk." Most of the restorative and endodontic treatment procedures involve generation of aerosols. Owing to the possibility of transmission of virus through aerosols, these procedures may transmit the disease to clinician or other patients. A comprehensive search of literature was conducted with the help of PubMed/MEDLINE and Scopus databases using a combination of terms, "COVID-19," "severe acute respiratory syndrome coronavirus 2," "aerosols," "restorative dentistry," and "endodontics." Along with universal precautions, some additional precautions need to be taken to prevent such transmission and cross-infection. This article reviews the research evidence about the role of aerosols in the transmission of COVID-19 and various measures which should be implemented during restorative and endodontic practice for the prevention of such transmission.

Global Oral Health Policies and Guidelines: Using Silver Diamine Fluoride for Caries Control

Silver diamine fluoride (SDF) was developed in Japan in the 1960s. It is a clear solution containing silver and fluoride ions. Because of its anti-bacterial and remineralizing effect, silver diamine fluoride has been used in managing dental caries for decades worldwide. This paper aims to summarize and discuss the global policies, guidelines, and relevant information on utilizing SDF for caries management. SDF can be used for treating dental caries in most countries. However, it is not permitted to be used in mainland China. Several manufacturers, mainly in Australia, Brazil, India, Japan, and the United States, produce SDF at different concentrations that are commercially available around the world. The prices differ between contents and brands. Different government organizations and dental associations have developed guidelines for clinical use of SDF. Dental professionals can refer to the specific guidelines in their own countries or territories. Training for using SDF is part of undergraduate and/or postgraduate curriculums in almost all countries. However, real utilization of SDF of dentists, especially in the private sector, remains unclear in most places because little research has been conducted. There are at least two ongoing regional-wide large-scale oral health programs, using SDF as one of the components to manage dental caries in young children (one in Hong Kong and one in Mongolia). Because SDF treatment does not require caries removal, and it is simple, non-invasive, and inexpensive, SDF is a valuable strategy for caries management in young children, elderly people, and patients with special needs. In addition, to reduce the risk of bacteria or virus transmission in dental settings, using SDF as a non-aerosol producing procedure should be emphasized under the COVID-19 outbreak.

"I guess it looks worse to me, it doesn't look like there's been a problem solved but obviously there is": a qualitative exploration of children's and their parents' views of silver diamine fluoride for the management of carious lesions in children

Background

Despite growing evidence to support the use of silver diamine fluoride (SDF) for managing carious lesions, and the increased interest in SDF worldwide, uptake in the UK remains limited. This study explored parents’ and children’s views and acceptability of SDF for the management of carious lesions in children.

Methods

Eleven semi-structured face-to-face interviews were conducted with 11 parent–child dyads recruited from patients attending Dundee Dental Hospital and School. Interviews were transcribed verbatim, coded and thematically analysed.

Results

Previous dental experience varied across all child participants. Of the 11 children, five had undergone general anaesthesia (GA) for multiple primary tooth extractions. Two had received SDF treatment. Child participants expressed concerns about being picked on by their peers, if they had discoloured anterior teeth. Younger children appeared less concerned about the discolouration and child’s gender did not appear to influence parents’ decision-making, nor the child’s preferences regarding the use of SDF. Parents considered SDF to be particularly useful for anxious or uncooperative children but raised concerns about potential bullying at schools due to the unacceptable dental aesthetics when SDF is applied to anterior teeth. They believed they may be judged by others as neglecting their child’s oral health due to the black staining. Both parents and children were more accepting of the SDF when applied to less-visible posterior teeth. Parents accepted the use of SDF if such treatment avoided extractions under GA.

Conclusion

Despite the unfavourable aesthetics of SDF (black staining), parents appreciated SDF treatment, especially for uncooperative or younger children. However, both parents and children shared concerns about bullying at schools as a consequence of the black staining. Raising awareness about SDF was identified as one approach to encourage the uptake of SDF.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01730-w.

CariesCare International adapted for the pandemic in children: Caries OUT multicentre single-group interventional study protocol

Background

Comprehensive caries care has shown effectiveness in controlling caries progression and improving health outcomes by controlling caries risk, preventing initial-caries lesions progression, and patient satisfaction. To date, the caries-progression control effectiveness of the patient-centred risk-based CariesCare International (CCI) system, derived from ICCMS™ for the practice (2019), remains unproven. With the onset of the COVID-19 pandemic a previously planned multi-centre RCT shifted to this “Caries OUT” study, aiming to assess in a single-intervention group in children, the caries-control effectiveness of CCI adapted for the pandemic with non-aerosols generating procedures (non-AGP) and reducing in-office time.

Methods

In this 1-year multi-centre single-group interventional trial the adapted-CCI effectiveness will be assessed in one single group in terms of tooth-surface level caries progression control, and secondarily, individual-level caries progression control, children’s oral-health behaviour change, parents’ and dentists’ process acceptability, and costs exploration. A sample size of 258 3–5 and 6–8 years old patients was calculated after removing half from the previous RCT, allowing for a 25% dropout, including generally health children (27 per centre). The single-group intervention will be the adapted-CCI 4D-cycle caries care, with non-AGP and reduced in-office appointments’ time. A trained examiner per centre will conduct examinations at baseline, at 5–5.5 months (3 months after basic management), 8.5 and 12 months, assessing the child’s CCI caries risk and oral-health behaviour, visually staging and assessing caries-lesions severity and activity without air-drying (ICDAS-merged Epi); fillings/sealants; missing/dental-sepsis teeth, and tooth symptoms, synthetizing together with parent and external-trained dental practitioner (DP) the patient- and tooth-surface level diagnoses and personalised care plan. DP will deliver the adapted-CCI caries care. Parents’ and dentists’ process acceptability will be assessed via Treatment-Evaluation-Inventory questionnaires, and costs in terms of number of appointments and activities. Twenty-one centres in 13 countries will participate.

Discussion

The results of Caries OUT adapted for the pandemic will provide clinical data that could help support shifting the caries care in children towards individualised oral-health behaviour improvement and tooth-preserving care, improving health outcomes, and explore if the caries progression can be controlled during the pandemic by conducting non-AGP and reducing in-office time.

Trial registration: Retrospectively-registered-ClinicalTrials.gov-NCT04666597-07/12/2020: https://register.clinicaltrials.gov/prs/app/action/SelectProtocol?sid=S000AGM4&selectaction=Edit&uid=U00019IE&ts=2&cx=uwje3h. Protocol-version 2: 27/01/2021.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12903-021-01674-1.

A Pan-Canadian narrative review on the protocols for reopening dental services during the COVID-19 pandemic

The current coronavirus disease 2019 (COVID-19) pandemic is impacting the way in which dental services are provided. The aim of this narrative review was twofold: to summarize key areas from the Canadian protocols available for the reopening and restructuring of dental services across the country and to critically review these protocols based on existing evidence. A narrative review of the existing Canadian protocols, written in English and French, was undertaken between April 15 and July 13, 2020. The protocols were obtained by searching through regulatory bodies and websites from professional organizations, and from personal contacts through academic institutions and policy leaders. The data extraction form focused only on protocols related to dentistry, and the information was compiled by a hired assistant. Content was categorized via group discussions with the research team on eight areas: office management and procedures, patient and staff screening, treatment procedures, office layout, risk reduction, personal protective equipment, supporting information, and length and readability. Thirteen protocols were identified and offered substantial variation in the level of details provided. All but two protocols specified proper donning/doffing of personal protective equipment, while all protocols recommended daily monitoring of COVID-19 related signs and symptoms in staff and patients. They varied in terms of recommended mask types, eye and face shield protection, and head coverings. While all protocols aimed at restructuring emergency dental services, their recommendations were often not based on the published evidence. This narrative review summarized key areas from 13 provincial and territorial protocols in Canada to help oral health care providers plan the reopening of their services. The information conveyed across all documents was clear, but variance highlights the need for a coordinated effort to develop an evidence-based document for dental practitioners.