Reducing bacterial aerosol contamination with a chlorhexidine gluconate pre-rinse

Efficacy of different mouthwashes against COVID-19: A systematic review and network meta-analysis

To evaluate the effectiveness of antiseptic mouthwashes in reducing SARS-CoV-2 load clinically and in vitro. A systematic electronic search (MEDLINE/Scopus/Cochrane) was conducted to identify prospective clinical and in vitro studies published between 2019 included and 16 June 2023 assessing the effectiveness of mouthwashes in reducing SARS-CoV-2 load in saliva or surrogates. Data were summarized in tables and a network meta-analysis was performed for clinical trials. Thirty-five studies (14 RCTs, 21 in vitro) fulfilled the inclusion criteria. The risk of bias was judged to be high for 2 clinical and 7 in vitro studies. The most commonly test product was chlorhexidine alone or in combination with other active ingredients, followed by povidone-iodine, hydrogen peroxide and cetylpyridinium chloride. Overall, the descriptive analysis revealed the effectiveness of the mouthwashes in decreasing the salivary viral load both clinically and in vitro. Network meta-analysis demonstrated a high degree of heterogeneity. Among these studies, only chlorhexidine 0.20% was associated to a significant Ct increase in the saliva 5 min after rinsing compared to non-active control (p = 0.027). Data from clinical and in vitro studies suggested the antiviral efficacy of commonly used mouthwashes. Large well-balanced trials are needed to identify the best rinsing protocols.

Efficacy of Oxygen-Enriched Mouthwash as a Pre-procedural Mouth Rinse Against Oral Microbes Produced During Ultrasonic Scaling

Aim Oxygen-enriched mouthwash products are based on oral topical oxygen therapy (OOT), which supports the formation of new blood vessels and the removal of toxins and waste products from the affected area and stimulates the synthesis of collagen. These antioxidant mouthwashes contain honey, lactoferrin, and sodium carbonate peroxide. Lactoferrin is an anti-inflammatory protein that binds the ferrous iron ions surrounding micro-organisms regulating bacterial growth. Hence, these products can be included as an adjunct to toothbrushing after oral surgeries and in the treatment of conditions like gingival inflammation and peri-implantitis. The aim of the study was to evaluate the efficacy of oxygen-enriched mouthwash as a pre-procedural mouth rinse against oral microbes in the aerosol produced during ultrasonic scaling. Materials and methods A total of 40 patients with an age range of 20-40 years who have been advised to undergo ultrasonic scaling were selected as study subjects and were randomly allocated to group 1 (test group; n = 20; blue®m mouthwash) and group 2 (control group; n = 20; chlorhexidine). After evaluating the initial bacterial load after the use of water (placebo) as pre-rinse on the patient's chest and shoulder areas in both experimental and control groups, both the group subjects were instructed to gargle with 10 ml of the provided mouth rinse for one minute before ultrasonic scaling procedure. Blood agar plates were placed at the patient's chest and shoulder area to collect the aerosol and were later incubated to assess the colony-forming units (CFUs). An independent t-test was done to compare the CFUs between the groups. Results The mean initial bacterial load after the use of water (placebo) as pre-rinse on the patients' chest area (122.4 ± 0.6) and shoulder area (109.3 ± 2.6) in the experimental group was similar to the bacterial load seen on the chest area (126.2 ± 4.8) and shoulder area (115.4 ± 3.8) in the control group. The CFUs found in blood agar plates placed on the chest (59.8 ± 2.5) and shoulder (35.3 ± 3.6) areas of patients in group 1 were less as compared to CFUs found in blood agar plates placed on the chest (104.8 ± 3.2) and shoulder (75.3 ± 2.8) areas of patients in group 2. The difference between both groups was statistically significant with a p-value of ≤0.05. Conclusion There is a reduction in the bacterial load in the aerosols that are emitted during the ultrasonic scaling procedure with the use of oxygen-enriched mouthwash as a pre-procedural rinse when compared with chlorhexidine.

Effectiveness of interventions to reduce aerosol generation in dental environments: A systematic review

Certain dental procedures produce high levels of aerosols containing pathogenic microorganisms, posing a risk for the transmission of infections in dental settings. This study aimed to assess the effectiveness of various aerosol mitigation interventions during clinical dental procedures in real-world environments. A systematic literature search was conducted in PubMed/MEDLINE, Scopus, Web of Science, and Embase for English studies up to March 2023 according to the PRISMA guidelines. Only peer-reviewed controlled clinical trials (CCT) or randomized controlled trials (RCT) studies involving human subjects were included. The risk of bias of selected researches were evaluated by two independent authors using the Cochrane Collaboration tool. The literature search yielded 3491 articles, of which 42 studies met the inclusion criteria and were included in this study. Most studies evaluated bacterial contamination in bio-aerosols, while the viral and fungal contamination was assessed in only three studies. Overall, various approaches have been applied in reducing aerosol contamination in clinical scenarios, including high-volume evacuators (HVE), mouse rinses and rubber dams, air cleaning systems, and high-efficiency particulate air (HEPA) filters. The available evidence suggests that various aerosol mitigation strategies could be implemented to decrease the risk of cross-infection during clinical dental procedures in real-world environments. However, further clinical trials are necessary to establish statistical validity in measuring aerosol contamination and mitigation, as well as to evaluate the risk of infection transmission for viral and fungal contamination.

Dental professionals' use of personal protective equipment during COVID-19: a cross-sectional study in China

Background

Appropriate use of personal protective equipment (PPE) could significantly reduce the risk of viral transmission and infection. This study aimed to assess the use of PPE among dentists during the COVID-19 pandemic in China, explore its influencing factors, and provide some practical recommendations.

Methods

An online cross-sectional survey was conducted among 384 Chinese dentists in September 2022. The questionnaire comprised a series of questions about demographic characteristics, compliance with proper PPE use, personal barriers to use, and exposure risk estimation.

Results

Of the 384 respondents, 57.3% had unacceptable compliance with the proper use of PPE during COVID-19. Medical surgical mask is the most common for dental professionals to wear (93.8%), followed by goggles or face shield (63.8%), and isolation gown (53.1%). Unexpectedly, only 63.3% of respondents always change masks with guidelines. The condition for changing goggles/face shields and isolation gowns is even worse (45.6 and 37.0%, respectively). Visual barriers, physical discomfort, complex procedures, and heavy workload were the most common personal barriers to use. According to the results of Chi-square test and correlation analysis, PPE use compliance was associated with age, years of practice, medical institution type, and exposure risk estimation.

Conclusion

Chinese dental professionals need to improve their compliance with the proper use of PPE, especially those in the 31-40 age group, with 11-15 experience years and working in private dental clinics. Increasing compliance with PPE may be achieved by addressing personal barriers to use, human resource shortages, and perceptions of exposure risk.

Preprocedural mouthwashes for infection control in dentistry-an update

OBJECTIVES

Aerosols and splatter are routinely generated in dental practice and can be contaminated by potentially harmful bacteria or viruses such as SARS-CoV-2. Therefore, preprocedural mouthwashes containing antiseptic agents have been proposed as a potential measure for infection control in dental practice. This review article aims to summarize the clinical (and, if insufficient, preclinical) evidence on preprocedural mouthwashes containing antiseptic agents and to draw conclusions for dental practitioners.

METHODS

Literature on preprocedural mouthwashes for reduction of bacterial or viral load in dental aerosols was searched and summarized.

RESULTS

Preprocedural mouthwashes, particularly those containing chlorhexidine digluconate (CHX), cetylpyridinium chloride (CPC), or essential oils (EO), can significantly reduce the bacterial load in dental aerosols. With respect to viruses such as HSV-1, there are too little clinical data to draw any clear recommendations. On the other hand, clinical data is consolidating that CPC-containing mouthwashes can temporarily reduce the intraoral viral load and infectivity in SARS-CoV-2 positive individuals. Nevertheless, potential risks and side effects due to regular antiseptic use such as ecological effects or adaptation of bacteria need to be considered.

CONCLUSIONS

The use of preprocedural mouthwashes containing antiseptics can be recommended according to currently available data, but further studies are needed, particularly on the effects on other viruses besides SARS-CoV-2. When selecting a specific antiseptic, the biggest data basis currently exists for CHX, CPC, EO, or combinations thereof.

CLINICAL RELEVANCE

Preprocedural mouthwashes containing antiseptics can serve as part of a bundle of measures for protection of dental personnel despite some remaining ambiguities and in view of potential risks and side effects.

Short- and long term antibacterial effects of a single rinse with different mouthwashes: A randomized clinical trial

Objectives

Reducing the microbial level in the aerosol created during dental procedures is essential to avoiding infections. The aim of this study was to examine the change in Streptococcus mutans (S. mutans) and the total bacterial load in human saliva in vivo after a single rinse with different mouthwashes.

Material and methods

One mL of unstimulated saliva was collected from volunteers with poor oral hygiene at baseline and 5 min after a 1-min rinsing with diluted Solumium Oral® (hyper-pure 0.0015% chlorine dioxide; ClO₂), Listerine Total Care®, Corsodyl® (0.2% chlorhexidine-digluconate; CHX), or BioGate Si*CLEAN for bacterial investigation. In a second study, volunteers rinsed with 0.003% ClO₂ or CHX for 1 min, and saliva was collected at baseline, after 5 min, and after 90 min. After plating, the total plate and S. mutans colony numbers were determined.

Results

In the first study, ClO₂ and CHX similarly reduced both total germ and S. mutans numbers, while Listerine Total Care® decreased only the S. mutans counts. BioGate Si*Clean had no effect on either the total germ or S. mutans numbers. In the second study, an increasing tendency toward bacterial regrowth was observed with CHX after 90 min compared to the 5-min value, while no change was measured after ClO₂ rinsing.

Conclusion

Hyper-pure ClO₂ rinsing may be a new promising preventive and therapeutic adjuvant in dental practice, as it is similar in effectiveness to the gold standard CHX-containing mouthwashes, especially in patients concerned with taste or tooth discoloration during oral health therapy.

Preprocedural mouth rinses for preventing transmission of infectious diseases through aerosols in dental healthcare providers

BACKGROUND

Aerosols and spatter are generated in a dental clinic during aerosol-generating procedures (AGPs) that use high-speed hand pieces. Dental healthcare providers can be at increased risk of transmission of diseases such as tuberculosis, measles and severe acute respiratory syndrome (SARS) through droplets on mucosae, inhalation of aerosols or through fomites on mucosae, which harbour micro-organisms. There are ways to mitigate and contain spatter and aerosols that may, in turn, reduce any risk of disease transmission. In addition to personal protective equipment (PPE) and aerosol-reducing devices such as high-volume suction, it has been hypothesised that the use of mouth rinse by patients before dental procedures could reduce the microbial load of aerosols that are generated during dental AGPs.

OBJECTIVES

To assess the effects of preprocedural mouth rinses used in dental clinics to minimise incidence of infection in dental healthcare providers and reduce or neutralise contamination in aerosols.

SEARCH METHODS

We used standard, extensive Cochrane search methods. The latest search date was 4 February 2022.

SELECTION CRITERIA

We included randomised controlled trials and excluded laboratory-based studies. Study participants were dental patients undergoing AGPs. Studies compared any preprocedural mouth rinse used to reduce contaminated aerosols versus placebo, no mouth rinse or another mouth rinse. Our primary outcome was incidence of infection of dental healthcare providers and secondary outcomes were reduction in the level of contamination of the dental operatory environment, cost, change in mouth microbiota, adverse events, and acceptability and feasibility of the intervention.

DATA COLLECTION AND ANALYSIS

Two review authors screened search results, extracted data from included studies, assessed the risk of bias in the studies and judged the certainty of the available evidence. We used mean differences (MDs) and 95% confidence intervals (CIs) as the effect estimate for continuous outcomes, and random-effects meta-analysis to combine data  MAIN RESULTS:  We included 17 studies with 830 participants aged 18 to 70 years. We judged three trials at high risk of bias, two at low risk and 12 at unclear risk of bias.  None of the studies measured our primary outcome of the incidence of infection in dental healthcare providers.  The primary outcome in the studies was reduction in the level of bacterial contamination measured in colony-forming units (CFUs) at distances of less than 2 m (intended to capture larger droplets) and 2 m or more (to capture droplet nuclei from aerosols arising from the participant's oral cavity). It is unclear what size of CFU reduction represents a clinically significant amount. There is low- to very low-certainty evidence that chlorhexidine (CHX) may reduce bacterial contamination, as measured by CFUs, compared with no rinsing or rinsing with water. There were similar results when comparing cetylpyridinium chloride (CPC) with no rinsing and when comparing CPC, essential oils/herbal mouthwashes or boric acid with water. There is very low-certainty evidence that tempered mouth rinses may provide a greater reduction in CFUs than cold mouth rinses. There is low-certainty evidence that CHX may reduce CFUs more than essential oils/herbal mouthwashes. The evidence for other head-to-head comparisons was limited and inconsistent.  The studies did not provide any information on costs, change in micro-organisms in the patient's mouth or adverse events such as temporary discolouration, altered taste, allergic reaction or hypersensitivity. The studies did not assess acceptability of the intervention to patients or feasibility of implementation for dentists.  AUTHORS' CONCLUSIONS: None of the included studies measured the incidence of infection among dental healthcare providers. The studies measured only reduction in level of bacterial contamination in aerosols. None of the studies evaluated viral or fungal contamination. We have only low to very low certainty for all findings. We are unable to draw conclusions regarding whether there is a role for preprocedural mouth rinses in reducing infection risk or the possible superiority of one preprocedural rinse over another. Studies are needed that measure the effect of rinses on infectious disease risk among dental healthcare providers and on contaminated aerosols at larger distances with standardised outcome measurement.

Efficacy of Combining an Extraoral High-Volume Evacuator with Preprocedural Mouth Rinsing in Reducing Aerosol Contamination Produced by Ultrasonic Scaling

The coronavirus disease pandemic has afforded dental professionals an opportunity to reconsider infection control during treatment. We investigated the efficacy of combining extraoral high-volume evacuators (eHVEs) with preprocedural mouth rinsing in reducing aerosol contamination by ultrasonic scalers. A double-masked, two-group, crossover randomized clinical trial was conducted over eight weeks. A total of 10 healthy subjects were divided into two groups; they received 0.5% povidone-iodine (PI), essential oil (EO), or water as preprocedural rinse. Aerosols produced during ultrasonic scaling were collected from the chest area (PC), dentist's mask, dentist's chest area (DC), bracket table, and assistant's area. Bacterial contamination was assessed using colony counting and adenosine triphosphate assays. With the eHVE 10 cm away from the mouth, bacterial contamination by aerosols was negligible. With the eHVE 20 cm away, more dental aerosols containing bacteria were detected at the DC and PC. Mouth rinsing decreased viable bacterial count by 31-38% (PI) and 22-33% (EO), compared with no rinsing. The eHVE prevents bacterial contamination when close to the patient's mouth. Preprocedural mouth rinsing can reduce bacterial contamination where the eHVE is positioned away from the mouth, depending on the procedure. Combining an eHVE with preprocedural mouth rinsing can reduce bacterial contamination in dental offices.

Aerosol generated by dental procedures: A scoping review

BACKGROUND

The current pandemic has raised awareness of aerosol dispersion in dental offices. This scoping review was conducted to assess the amount and spread of aerosol generated by dental procedures.

METHODS

This scoping review followed the PRISMA-ScR protocol and was conducted by searching multiple databases adopting a core search structure for each database. Detailed eligibility criteria were applied. The authors placed no restrictions on study design, year of publication, and study location. The literature search was updated on September 15, 2021.

RESULTS

A total of 51 papers were included in this scoping review. The risk of bias assessment was not conducted as per guidelines. The majority of studies found microorganisms, bloodstains, splatters of aerosol, and particles in the air part of the search strategy. Publication dates ranged from 1969 to 2021. Data came from different dental settings locations. Several factors were identified that have an effect on the amount and spread of the aerosol and spatter.

CONCLUSION

Although it is clear that the microbial contamination occurred mainly during aerosol-generating dental procedures, our understanding of the contamination level, spread, and half-life are limited.

Effectiveness of mouthwash against viruses: 2020 perspective. A systematic review

INTRODUCTION

Antiseptic mouthwash is widely recommended to treat various oral diseases as well as to improve oral health. Most of the dental procedures lead to the generation of aerosols. These aerosols have a high potential to transmit disease. Preprocedural oral rinse with antimicrobial agents in the form of mouthwashes reduces the bacterial and viral load many folds. The purpose of this review was to summarize the effectiveness of mouthwash against viruses affecting human beings.

EVIDENCE ACQUISITION

Search engines like PubMed, Google Scholar, and others were used to search the electronic database. Articles were identified in which the effectiveness of antiseptic mouth rinse against the virus was tested. A comprehensive search strategy was designed to select the articles and then independently screened for eligibility.

EVIDENCE SYNTHESIS

A total of 9624 articles out of the 13 titles met the eligibility criteria. The selected papers were included in the present manuscript according to their relevance to the topic. Authors searched the most used chemicals as mouthwashes but records of three types of mouthwash tested against various types of viruses i.e. chlorhexidine gluconate, Povidone-iodine and essential oil containing mouthwash (Listerine) were found.

CONCLUSIONS

Povidone-iodine mouth rinse is effective in reducing viral load either in-vitro or in-vivo conditions. Chlorhexidine gluconate mouthwash and essential oils have shown its effectiveness in a few studies. Insufficient evidence is available to support the claim that oral antiseptics can reduce the risk of developing viral loads in humans or the rate of progression of diseases caused by viruses.

In vivo evaluation of the virucidal efficacy of chlorhexidine and povidone-iodine mouthwashes against salivary SARS-CoV-2. A randomized-controlled clinical trial

Objectives

The oral cavity is potentially high-risk transmitter of COVID-19. Antimicrobial mouthrinses are used in many clinical preprocedural situations for decreasing the risk of cross-contamination in the dental setting. It is important to investigate the efficacy of mouthwash solutions against salivary SARS-CoV-2 in order to reduce the exposure of the dental team during dental procedures.

Aims

The aim of this in vivo study was to evaluate the efficacy of 2 preprocedural mouthrinses in the reduction of salivary SARS-CoV-2 viral load and to compare the results of the mouthwashes to a control group.

Materials and Methods

In this randomized-controlled clinical trial, studied group comprised laboratory-confirmed COVID-19 positive patients through nasopharyngeal swabs. Participants were divided into 3 groups. For 30 s, the control group mouthrinsed with distilled water, the Chlorhexidine group mouthrinsed with 0.2% Chlorhexidine and the Povidone-iodine group gargled with 1% Povidone-iodine. Saliva samples were collected before and 5 min after mouthwash. SARS-CoV-2 rRT-PCR was then performed for each sample. Evaluation of the efficacy was based on difference in cycle threshold (Ct) value. The analysis of data was carried out using GraphPad Prism version 5 for Windows. Kristal wullis and Paired t-test were used. A probability value of less than 0.05 was regarded as statistically significant.

Results

Sixty-one compliant participants (36 female and 25 male) with a mean age 45.3 ± 16.7 years-old were enrolled. A significant difference was noted between the delta Ct of distilled water wash and each of the 2 solutions Chlorhexidine 0.2% (P = .0024) and 1% Povidone-iodine (P = .012). No significant difference was found between the delta Ct of patients using Chlorhexidine 0.2% and 1% Povidone-iodine solutions (P = .24). A significant mean Ct value difference (P < .0001) between the paired samples in Chlorhexidine group (n = 27) and also in Povidone-iodine group (n = 25) (P < .0001) was found. In contrast, no significant difference (P = .566) existed before and after the experiment in the control group (n = 9).

Conclusion

Chlorhexidine 0.2% and 1% Povidone-iodine oral solutions are effective preprocedural mouthwashes against salivary SARS-CoV-2 in dental treatments. Their use as a preventive strategy to reduce the spread of COVID-19 during dental practice should be considered.

Size-resolved spatial distribution analysis of aerosols with or without the utilization of a novel aerosol containment device in dental settings

The coronavirus disease 2019 pandemic has imposed unprecedented occupational challenges for healthcare professionals. In dentistry, handheld instruments such as air and electric handpieces, ultrasonic scalers, and air/water syringes are capable of generating aerosols, droplets, and splatter, thereby exposing dental professionals to airborne contaminants such as viruses, bacteria, and fungi. The objective of the present study was to determine the spatial distribution of aerosols by size (0.30 to 20.00 μm) and the efficacy of a novel aerosol containment device (ACD) in a large operatory room with 12 dental chairs. Real-time portable laser aerosol spectrometers were used to measure the size-resolved number concentration of aerosols generated by a collision nebulizer. Results reported demonstrate that aerosol number concentrations significantly decreased as a function of distance with or without the utilization of the ACD. The ACD was able to efficiently decrease (up to 8.56-fold) the number and size distribution of particles in a large dental clinic. The novel device demonstrated higher efficiency for particles shown to contain the highest levels of severe acute respiratory syndrome coronavirus 2 in Chinese hospitals, thereby showing great promise to potentially decrease the spreading of nosocomial pathogens in dental settings.

Airborne particles and microorganisms in a dental clinic: Variability of indoor concentrations, impact of dental procedures, and personal exposure during everyday practice

This study presents for the first time comprehensive measurements of the particle number size distribution (10 nm to 10 μm) together with next-generation sequencing analysis of airborne bacteria inside a dental clinic. A substantial enrichment of the indoor environment with new particles in all size classes was identified by both activities to background and indoor/outdoor (I/O) ratios. Grinding and drilling were the principal dental activities to produce new particles in the air, closely followed by polishing. Illumina MiSeq sequencing of 16S rRNA of bioaerosol collected indoors revealed the presence of 86 bacterial genera, 26 of them previously characterized as potential human pathogens. Bacterial species richness and concentration determined both by qPCR, and culture-dependent analysis were significantly higher in the treatment room. Bacterial load of the treatment room impacted in the nearby waiting room where no dental procedures took place. I/O ratio of bacterial concentration in the treatment room followed the fluctuation of I/O ratio of airborne particles in the biology-relevant size classes of 1-2.5, 2.5-5, and 5-10 μm. Exposure analysis revealed increased inhaled number of particles and microorganisms during dental procedures. These findings provide a detailed insight on airborne particles of both biotic and abiotic origin in a dental clinic.

Clinical Guidelines for Dentistry in China During the Coronavirus Disease 2019 Pandemic

Preventing the spread of Coronavirus Disease 2019 (COVID-19) has become the focus of epidemiologists as the highly infectious respiratory disease spreads primarily by close, person-to-person contact via droplets or the skin. Aerosol dissemination may occur in a closed, high-aerosol environment. The aerosols generated in dental procedures can pollute surrounding air and device surfaces. In this paper, we summarize prevention and control measures relating to dentistry. We focus on the relationship between COVID-19 and dental disease prevention and control in dental treatment procedures and imaging examinations, oral health education and perspectives, and guidance for the practice of dentistry during the COVID-19 pandemic to provide a consistent and broadly endorsed standard for dental hospital and clinics.

Effectiveness of Pre-procedural Mouth Rinses in Reducing Aerosol Contamination During Periodontal Prophylaxis: A Systematic Review

Background: Aerosol-producing dental procedures are of concern in the spread of infections, especially during the COVID-19 pandemic. Periodontal prophylaxis is the most common aerosol-producing procedure conducted in dental practice globally. During COVID-19, many national and international organizations advocated the use of pre-procedural mouth rinsing to prevent the spread of infections from aerosol-generating procedures in the dental setting; however, many questioned the scientific basis for such recommendations. Objective: This systematic review aimed to evaluate the effectiveness of pre-procedural rinsing when preforming periodontal prophylaxis in reducing aerosol contamination in the dental setting. Methods: A comprehensive standardized search strategy was employed, informed by a defined PICO question across four electronic databases. The review of the literature was conducted using the PRISMA framework. Agreement between assessors was determined throughout. Synthesis of study characteristics and key outcomes were conducted. Cochrane's risk-of-bias tool for randomized trials (RoB 2) was employed to assess the quality/bias among studies. Results: The initial search yielded 731 citations across the four databases; 95 potentially effective studies were identified, with 56 effective studies found. Thirty randomized control trial studies were identified, 21 with a focus on effectiveness of pre-procedural mouth rinsing, involving 984 participants (aged 18-70). Agreement between assessors was high (Kappa >0.80). Various pre-procedural mouth rinses were tested, most frequently chlorhexidine (CHX) in 18 studies. The concentrations, volume, and prescribed duration of rinsing varied among studies, hampering meta-analyses. Nonetheless, all studies identified significant reductions in bacterial contamination, as measured by colony forming units (cfu). The effectiveness of CHX over other agents was evident with more than half of the studies (7/15) reporting over a 70% reduction in bacterial contamination (cfu). There were concerns over the risk of bias in most studies (76.2%); 19.0% had a high risk of bias and 4.8% were of low risk of bias. Conclusion: There is substantial evidence to support pre-procedural mouth rinsing, such as with chlorohexidine, to effectively reduce aerosol contamination when performing periodontal prophylaxis compared to mouth rinsing with water or not rinsing.

Safety protocols for dental care during the COVID-19 pandemic: the experience of a Brazilian hospital service

The coronavirus disease (COVID-19) has been prioritized in relation to other illnesses considered critical, such as cancer, cardiovascular diseases/stroke, diabetes, and autoimmune diseases. The management of patients with these diseases involves dental care to reduce systemic complications caused by odontogenic infections, and/or to treat oral manifestations of systemic comorbidities. In this regard, the dental care of these individuals must be guaranteed during the pandemic. Although a high risk of exposure to and catching of COVID-19 is expected to befall dental professionals, biosafety guidelines reduce the likelihood of infection. Thus, the current scenario poses challenges, and offers decision-making approaches and tools that facilitate the management of individuals with oral manifestations of chronic and/or critical diseases, using hospital-based services. This article presents an overview for hospital service providers who are at the forefront of COVID-19 care, including a secure protocol, and clinical guidelines based on the experience of the Hospital das Clínicas in Belo Horizonte, a public referral service, supported by the Brazilian National Health System.

Dental periodontal procedures: a systematic review of contamination (splatter, droplets and aerosol) in relation to COVID-19

INTRODUCTION

The emergence of the SARS-CoV-2 virus and subsequent COVID-19 pandemic has had a significant effect on the delivery of routine dentistry; and in particular, periodontal care across the world. This systematic review examines the literature relating to splatter, droplet settle and aerosol for periodontal procedures and forms part of a wider body of research to understand the risk of contamination in relation to periodontal care procedures relevant to COVID-19.

METHODS

A search of the literature was carried out using key terms and MeSH words relating to the review questions. Sources included Medline (OVID), Embase (OVID), Cochrane Central Register of Controlled Trials, Scopus, Web of Science and LILACS, ClinicalTrials.Gov . Studies meeting inclusion criteria were screened in duplicate and data extraction was carried out using a template. All studies were assessed for methodological quality and sensitivity. Narrative synthesis was undertaken.

RESULTS

Fifty studies were included in the review with procedures including ultrasonic scaling (n = 44), air polishing (n = 4), prophylaxis (n = 2) and hand scaling (n = 3). Outcomes included bacterial (colony-forming units e.g. on settle plates) or blood contamination (e.g. visible splatter) and non bacterial, non blood (e.g. chemiluminescence or coloured dyes) contamination. All studies found contamination at all sites although the contamination associated with hand scaling was very low. Contamination was identified in all of the studies even where suction was used at baseline. Higher power settings created greater contamination. Distribution of contamination varied in relation to operator position and was found on the operator, patient and assistant with higher levels around the head of the operator and the mouth and chest of the patient. Settle was identified 30 min after treatments had finished but returned to background levels when measured at or after an hour. The evidence was generally low to medium quality and likely to underestimate contamination.

CONCLUSION

Ultrasonic scaling, air polishing and prophylaxis procedures produce contamination (splatter, droplets and aerosol) in the presence of suction, with a small amount of evidence showing droplets taking between 30 min and 1 h to settle. Consideration should be given to infection control, areas of cleaning particularly around the patient and appropriate personal protective equipment, with particular attention to respiratory, facial and body protection for these procedures. In addition, the use of lower power settings should be considered to reduce the amount and spread of contamination.

The efficacy of bio-aerosol reducing procedures used in dentistry: a systematic review

BACKGROUND AND OBJECTIVE

Bio-aerosols, are routinely generated and airborne in clinical dentistry due to the operative instrumentation within an oral environment bathed in salivary organisms. SARS-CoV-2 transmission being responsible for the current pandemic, appears through airborne aerosols and droplets, thus, there has been an intense focus on such aerosol-generating procedures, and their reduction. Hence the objective of this systematic review was to evaluate available data on three major measures: rubber dam application, pre-procedural oral rinse, and high-volume evacuators (HVE) aimed at reducing bio-aerosols.

METHOD

PubMed via Ovid MEDLINE, EBSCO host, Cochrane Library and Web of Science databases were searched between 01 January 1985 and 30 April 2020.

RESULTS

A total of 156 records in English literature were identified, and 17 clinical studies with 724 patients included in the final analysis. Eligible articles revealed the inadequacy of three principle approaches used in contemporary dental practice to minimize such bio-aerosols, rubber dam application, pre-procedural oral rinses, and HVE. The latter is an extremely effective method to reduce bio-aerosols in dentistry, although no single method can provide blanket cover.

CONCLUSION

Present systematic review indicates that employing combination strategies of rubber dam, with a pre-procedural antimicrobial oral rinse, and HVE may contain bio-aerosols during operative procedures.

A systematic review of droplet and aerosol generation in dentistry

OBJECTIVES

This review aimed to identify which dental procedures generate droplets and aerosols with subsequent contamination, and for these, characterise their pattern, spread and settle.

DATA RESOURCES

Medline(OVID), Embase(OVID), Cochrane Central Register of Controlled Trials, Scopus, Web of Science and LILACS databases were searched for eligible studies from each database's inception to May 2020 (search updated 11/08/20). Studies investigating clinical dental activities that generate aerosol using duplicate independent screening. Data extraction by one reviewer and verified by another. Risk of bias assessed through contamination measurement tool sensitivity assessment.

STUDY SELECTION

A total eighty-three studies met the inclusion criteria and covered: ultrasonic scaling (USS, n = 44), highspeed air-rotor (HSAR, n = 31); oral surgery (n = 11), slow-speed handpiece (n = 4); air-water (triple) syringe (n = 4), air-polishing (n = 4), prophylaxis (n = 2) and hand-scaling (n = 2). Although no studies investigated respiratory viruses, those on bacteria, blood-splatter and aerosol showed activities using powered devices produced greatest contamination. Contamination was found for all activities, and at the furthest points studied. The operator's torso, operator's arm and patient's body were especially affected. Heterogeneity precluded inter-study comparisons but intra-study comparisons allowed construction of a proposed hierarchy of procedure contamination risk: higher (USS, HSAR, air-water syringe, air polishing, extractions using motorised handpieces); moderate (slow-speed handpieces, prophylaxis, extractions) and lower (air-water syringe [water only] and hand scaling).

CONCLUSION

Gaps in evidence, low sensitivity of measures and variable quality limit conclusions around contamination for procedures. A hierarchy of contamination from procedures is proposed for challenge/verification by future research which should consider standardised methodologies to facilitate research synthesis.

CLINICAL SIGNIFICANCE

This manuscript addresses uncertainty around aerosol generating procedures (AGPs) in dentistry. Findings indicate a continuum of procedure-related aerosol generation rather than the common binary AGP or non-AGP perspective. The findings inform discussion around AGPs and direct future research to support knowledge and decision making around COVID-19 and dental procedures.

COVID-19 and Oral Surgery: A narrative review of preoperative mouth rinses

OBJECTIVE

To provide a narrative review of the preprocedural mouth rinse protocols suggested for oral surgery in order to contrast the presence of SARS-CoV-2 in aerosol.

SOURCES AND METHODS

Electronic searches were performed in medical databases PubMed, Medline, CINAHN and Scopus to identify relevant studies published up until the third week of April 2020. This research was supplemented by exploration through a web-based search engine as well as a manual search for international and national guidelines. Studies and protocols which suggested preoperative mouth rinsing as a recommended measure during the COVID-19 outbreak were included. Given the small number of studies, a narrative literature review was conducted. In total, 15 references (11 articles and 4 guidelines) were considered relevant and were critically analysed.

CONCLUSION

The findings show a high heterogeneity in the protocols suggested. Further research is required to better understand the viral features and epidemiologic characteristics of this new virus and to test the efficacy of commonly used antiseptics against SARS-CoV-2 in future clinical trials. However, the use of chlorhexidine, hydrogen peroxide, PVP-I and cetylpyridinium chloride in contrasting the spread of Covid-19 is described as advisable and substantial in different publications.

A clinical study measuring dental aerosols with and without a high-volume extraction device

Introduction External high-volume extraction (HVE) devices may offer a way to reduce any aerosol particulate generated.Aims The aim of this study was to measure the particle count during dental aerosol generating procedures and compare the results with when a HVE device is used.Design A comparative clinical study measuring the amount of PM1, PM2.5 and PM10 aerosol particulate with and without the use of an external HVE device was undertaken.Materials and methods In total, ten restorative procedures were monitored with an industrial Trotec PC220 particle counter. The intervention was an external HVE device.Main outcome methods The air sampler was placed at the average working distance of the clinicians involved in the study - 420 mm.Results In the present study, aerosol particulate was recorded at statistically significantly increased levels during dental procedures without an external HVE deviceversus with the device.Discussion The null hypothesis was rejected, in that significant differences were found between the results of the amount of aerosol particle count with and without a HVE device.Conclusion If the results of the present study are repeated in an in vivo setting, an external high-volume suction device may potentially show a lower risk of transmission of viral particulate.

Minimizing the aerosol-generating procedures in orthodontics in the era of a pandemic: Current evidence on the reduction of hazardous effects for the treatment team and patients

The purpose of this critical review is to list the sources of aerosol production during orthodontic standard procedure, analyze the constituent components of aerosol and their dependency on modes of grinding, the presence of water and type of bur, and suggest a method to minimize the quantity and detrimental characteristics of the particles comprising the solid matter of aerosol. Minimization of water-spray syringe utilization for rinsing is suggested on bonding related procedures, while temporal conditions as represented by seasonal epidemics should be considered for the decision of intervention scheme provided as a preprocedural mouth rinse, in an attempt to reduce the load of aerosolized pathogens. In normal conditions, chlorhexidine 0.2%, preferably under elevated temperature state should be prioritized for reducing bacterial counts. In the presence of oxidation vulnerable viruses within the community, substitute strategies might be represented by the use of povidone iodine 0.2%-1%, or hydrogen peroxide 1%. After debonding, extensive material grinding, as well as aligner related attachment clean-up, should involve the use of carbide tungsten burs under water cooling conditions for cutting efficiency enhancement, duration restriction of the procedure, as well as reduction of aerosolized nanoparticles. In this respect, selection strategies of malocclusions eligible for aligner treatment should be reconsidered and future perspectives may entail careful and more restricted utilization of attachment grips. For more limited clean-up procedures, such as grinding of minimal amounts of adhesive remnants, or individualized bracket debonding in the course of treatment, hand-instruments for remnant removal might well represent an effective strategy. Efforts to minimize the use of rotary instrumentation in orthodontic settings might also lead the way for future solutions. Measures of self-protection for the treatment team should never be neglected. Dressing gowns and facemasks with filter protection layers, appropriate ventilation and fresh air flow within the operating room comprise significant links to the overall picture of practice management. Risk management considerations should be constant, but also updated as new material applications come into play, while being grounded on the best available evidence.

Interventions to Reduce Aerosolized Microbes in Dental Practice: A Systematic Review with Network Meta-analysis of Randomized Controlled Trials

The aim of this systematic review and network meta-analysis was to identify and rank the effectiveness of different interventions used in dental practice to reduce microbial load in aerosolized compounds. Seven electronic databases were searched to April 6, 2020, for randomized controlled trials (RCTs) or nonrandomized prospective studies in the field. Study selection, data extraction, and risk-of-bias assessment were performed for all included studies, while the outcome of interest pertained to differences in bacterial load quantification through the use of different interventions prior to aerosol-generating procedures in dental practices. Random effects frequentist network meta-analysis was performed, with mean difference (MD) and 95% CI as the effect measure. Confidence in the documented evidence was assessed through the newly fueled CINeMA framework (Confidence in Network Meta-analysis) based on the GRADE approach (Grading of Recommendations, Assessment, Development and Evaluation). Twenty-nine clinical trials were deemed eligible, 21 RCTs and 8 nonrandomized studies, while 11 RCTs contributed to the network meta-analysis, comprising 10 competing interventions. Tempered chlorhexidine (CHX) 0.2% as compared with nonactive control mouth rinse, prior to routine ultrasonic scaling, was most effective toward reduced postprocedural bacterial load with an MD of -0.92 (95% CI, -1.54 to -0.29) in log₁₀ bacterial CFUs (colony-forming units). For CHX 0.2%, an MD of -0.74 (95% CI, -1.07 to -0.40) was observed as compared with control. Tempered CHX 0.2% presented the highest probabilities of being ranked the most effective treatment (31.2%). Level of confidence varied from very low to moderate across all formulated comparisons. These findings summarize the current state of research evidence in the field of aerosolized bacteria in dentistry. Instigated by the era of SARS-CoV-2 pandemic, the stipulation of a broader evaluation of the aerosolized microbes, including viruses, potentially coupled with disinfectant-based prevention schemes should be prioritized.

Topographic aspects of airborne contamination caused by the use of dental handpieces in the operative environment

BACKGROUND

The use of dental handpieces produces aerosols containing microbial agents, bacteria, and viruses representing a high-risk situation for airborne cross infections. The aim of this study was to map and quantify the biological contamination of a dental operatory environment using a biological tracer.

METHODS

Streptococcus mutans suspension was infused into the mouth of a manikin, and an operator performed standardized dental procedures using an air turbine, a contra-angle handpiece, or an ultrasonic scaler. The presence of the tracer was measured at 90 sites on the dental unit and the surrounding surfaces of the operatory environment.

RESULTS

All tested instruments spread the tracer over the entire dental unit and the surrounding environment, including the walls and ceiling. The pattern and degree of contamination were related to the distance from the infection source. The maximum distance of tracer detection was 360 centimeters for air turbine, 300 cm for contra-angle handpiece, and 240 cm for ultrasonic scaler. No surface of the operative environment was free from the tracer after the use of the air turbine.

CONCLUSIONS

Attention should be paid to minimize or avoid the use of rotary and ultrasonic instruments when concerns for the airborne spreading of pandemic disease agents are present.

PRACTICAL IMPLICATIONS

This study supports the recommendations of dental associations to avoid treatments generating aerosols, especially during pandemic periods. Guidelines for the management of dental procedures involving aerosols, as well as methods for the modification of aerosols aimed to inactivate the infective agent, are urgently needed.

Is the oral cavity relevant in SARS-CoV-2 pandemic?

Objectives

Recent scientific evidences suggest a relevant role of the oral cavity in the transmission and pathogenicity of SARS-CoV-2.

Methods

A literature search was performed in PubMed, up to April 30, 2020, focusing on SARS-CoV-2, COVID-19, oral cavity, and antimicrobial agents.

Results

Oral viral load of SARS-CoV-2 has been associated with the severity of COVID-19, and thus, a reduction in the oral viral load could be associated with a decrease in the severity of the condition. Similarly, a decrease in the oral viral load would diminish the amount of virus expelled and reduce the risk of transmission, since (i) during the first 10 days, the virus mainly accumulates at the nasal, oral, and pharyngeal area; (ii) the number of angiotensin-converting enzyme (ACE2) receptor is greater in the salivary glands as compared with the lungs; and (iii) salivary droplets represent the most relevant transmission route. To reduce the oral viral load, antiseptic agents may be used, although the evidence on its efficacy is indirect and weak.

Conclusions

Antiseptic mouth rinses, such as those containing cetylpyridinium chloride or povidone-iodine, may be able to decrease the severity of COVID-19 by reducing oral viral load in infected subjects and decreasing the risk of transmission by limiting viral load in droplets, generated in normal life, or in aerosols, produced during dental procedures. Well-designed clinical and preclinical research must be conducted to support these hypotheses.

Clinical relevance

Antiseptic mouth rinses may help in decreasing the severity of COVID-19 and in reducing the risk of transmission.

Qualitative and quantitative analysis of bacterial aerosols in dental clinical settings: Risk exposure towards dentist, auxiliary staff, and patients

INTRODUCTION

Cross-infection or contamination are the major threats related to any medical profession. Microorganisms present in the dental clinic can cause cross-infection to the dentist, auxiliary staff and even towards the patients.

AIMS

The study was conducted to assess the level of atmospheric microbial contamination and composition of aerosols before, during and after dental treatment procedures in four clinical settings.

METHODS AND MATERIALS

The present study was conducted over a two-week period in a private dental college setting. An equal number of culture medium plates (blood agar) were placed 30 min prior to the initiation of work sessions in the selected area and 1 h after the working session began and after 2 h of cessation of the working period. After the collection of samples, the culture medium plates were incubated aerobically at 37°C in an incubator for 48 h. The number of colonies was expressed as colonies per media plate. After counting the colonies bacterial cell morphology was determined by a microscopic examination using a Reichert-Jung Series 150 light microscope.

STATISTICAL ANALYSIS

Statistical analysis such as ANOVA test for mean values and post hock was done using statistical package for social sciences (SPSS).

RESULTS

It shows that colony count increased after the working session and which reduced by itself once the working session was concluded which was significant (P < 0.001). The highest increase in the mean colony count was found in the department of periodontology during the treatment sessions. In the blood agar plates, the S. epidermidis was found maximum 62%, micrococcus was 22%, diphtheroid was 10%, fungi 4% and the least S. aureus 2%.

CONCLUSION

This study demonstrates that aerosols increase during and after work sessions and, therefore, increases the chance for infectious agent transmission in clinical settings.

Effect of aloe vera as a preprocedural rinse in reducing aerosol contamination during ultrasonic scaling

Background:

The use of preprocedural mouth rinse is one of the recommended ways to reduce aerosol contamination during ultrasonic scaling. Different agents have been tried as preprocedural mouth rinse. Chlorhexidine and povidone-iodine significantly reduce the viable microbial content of aerosol when used as a preprocedural rinse. Studies have shown that aloe vera (AV) mouthwash is equally effective as chlorhexidine in reducing plaque and gingivitis. There is no published literature on the role of AV as a preprocedural mouth rinse. Hence, this study compared the effect of 94.5% AV to 0.2% chlorhexidine gluconate (CHX) and 1% povidone-iodine (PVP-I) as preprocedural mouth rinses in reducing the aerosol contamination by ultrasonic scaling.

Materials and Methods:

Sixty subjects were divided into three groups based on the preprocedural rinse use (0.2% CHX, 1% PVP-I, and 94.5% AV). Ultrasonic scaling was done for 20 min in the same closed operatory for all the subjects after keeping blood agar plates open at two standardized locations. Colony forming units (CFUs) on blood agar plates were counted, and predominant bacteria were identified after incubation at 37°C for 48 h.

Results:

There was statistically significant difference in the CFU counts between CHX group and PVP-I group and between AV group and PVP-I group. There was no difference between CHX group and AV group at both the locations.

Conclusion:

94.5% AV as a preprocedural rinse is better than 1% PVP-I and comparable to 0.2% CHX in reducing CFU count.

2019 AAHA Dental Care Guidelines for Dogs and Cats*

The 2019 AAHA Dental Care Guidelines for Dogs and Cats outline a comprehensive approach to support companion animal practices in improving the oral health and often, the quality of life of their canine and feline patients. The guidelines are an update of the 2013 AAHA Dental Care Guidelines for Dogs and Cats. A photographically illustrated, 12-step protocol describes the essential steps in an oral health assessment, dental cleaning, and periodontal therapy. Recommendations are given for general anesthesia, pain management, facilities, and equipment necessary for safe and effective delivery of care. To promote the wellbeing of dogs and cats through decreasing the adverse effects and pain of periodontal disease, these guidelines emphasize the critical role of client education and effective, preventive oral healthcare.

Comparative evaluation of the chlorhexidine and cinnamon extract as ultrasonic coolant for reduction of bacterial load in dental aerosols

Background:

Ultrasonic instruments generate aerosols with significantly greater number of bacteria. Preprocedural mouthrinses or chemotherapeutic coolants are used for the reduction of bacterial load in dental aerosols. The use of chlorhexidine as an ultrasonic coolant has been well established. However, this application has not yet been investigated for cinnamon extract which is known to have antibacterial and anti-inflammatory properties in vivo.

Aim:

The aim of this study is to compare and evaluate the efficacy of chlorhexidine and cinnamon extract as an ultrasonic coolant in reduction of aerosol contamination and biofilm formation during ultrasonic scaling in comparison with the distilled water (DW).

Materials and Methods:

Sixty patients diagnosed with moderate-to-severe gingivitis were randomly divided into three groups of twenty patients each undergoing ultrasonic scaling. For Group I, chlorhexidine was used as an ultrasonic coolant; for Group II, cinnamon extract was used; and Group III was served as control where DW was used. The aerosols from ultrasonic units were collected on two blood agar plates at three different positions. Both the plates from each position were incubated aerobically for 48 h. The total number of colony-forming units were counted as mean ± standard deviation and statistically analyzed. In addition, biofilm sampling of dental unit waterlines (DUWLs) was also done to evaluate the effect of these antimicrobials. Apart from microbial examination, clinical parameters such as plaque index and gingival index were also evaluated at baseline and 1-month follow-up.

Results:

Chlorhexidine and cinnamon both were equally effective (P > 0.05) in reducing the bacterial count in aerosols and biofilm in DUWL as compared to DW when used as ultrasonic cooling agent.

Conclusion:

Both cinnamon and chlorhexidine used as an ultrasonic device coolant through DUWLs effectively helped in the reduction of bacterial count in dental aerosols.

Assessment of Capacity to Capture DNA Aerosols by Clean Filters for Molecular Biology Experiments

Experimental contamination by exogenous DNA is a major issue in molecular biological studies for data quality and its management. We herein assessed DNA aerosols for the risk of contamination and tested the capacity of clean air filters to trap and remove DNA aerosols. DNA aerosols were generated by atomizing a DNA solution and introduced into a laminar flow clean air unit. Capture and detection performed upstream and downstream of the clean air unit showed that a significant fraction (>99.96%) of introduced molecules was trapped and removed by the filter. Although DNA aerosols appear to be an avoidable source of exogenous contamination, a clearer understanding and careful experimental procedures are needed in order to perform contamination-free, high-quality molecular biology experiments.

Effectiveness of a pre-procedural mouthwash in reducing bacteria in dental aerosols: randomized clinical trial

The aim of this randomized, single blinded clinical trial was to evaluate the effect of a pre-procedural mouthwash containing cetylpyridinium chloride (CPC), zinc lactate (Zn) and sodium fluoride (F) in the reduction of viable bacteria in oral aerosol after a dental prophylaxis with ultrasonic scaler. Sixty systemically healthy volunteers receiving dental prophylaxis were randomly assigned to one of the following experimental groups (15 per group): (i) rinsing with 0.075% CPC, 0.28% Zn and 0.05% F (CPC+Zn+F), (ii) water or (iii) 0.12% chlorhexidine digluconate (CHX), and (iv) no rinsing. Viable bacteria were collected from different locations in the dental office on enriched TSA plates and anaerobically incubated for 72 hours. The colonies were counted and species were then identified by Checkerboard DNA-DNA Hybridization. The total number of colony-forming units (CFUs) detected in the aerosols from volunteers who rinsed with CPC+Zn+F or CHX was statistically significantly (p<0.05) lower than of those subjects who did not rinse or who rinsed with water. When all locations were considered together, the aerosols from the CPC+Zn+F and CHX groups showed, respectively, 70% and 77% fewer CFUs than those from the No Rinsing group and 61% and 70% than those from the Water group. The mean proportions of bacterial species from the orange complex were statistically significantly (p<0.05) lower in aerosols from the CPC+Zn+F and CHX groups compared with the others two groups. In conclusion, the mouthwash containing CPC+Zn+F, is effective in reducing viable bacteria in oral aerosol after a dental prophylaxis with ultrasonic scaler.

Comparative Evaluation of Two Different Ultrasonic Liquid Coolants on Dental Aerosols

INTRODUCTION

Dentists are more prone for developing infectious diseases especially related to respiratory system. The ultrasonic scaler which is a major source of dental aerosol production is most frequently used contrivance in a dental set up.

AIM

The aim of this study was to evaluate the effect of povidone iodine and chlorhexidine gluconate as an ultrasonic liquid coolant on aerosols in comparison with distilled water. The objectives of this study were to compare the potency of povidone iodine and chlorhexidine gluconate on reducing dental aerosols and quantitative assessment of microbial content of dental aerosols at right, left and behind the dental chair.

MATERIALS AND METHODS

In this study 30 subjects were selected who fulfilled the inclusion criteria and were divided into three groups. Group 1 (Control group): Ultrasonic scaling with distilled water (10 subjects), Group 2 (Test group): Ultrasonic scaling with 2% povidone iodine (10 subjects), Group 3 (Test group): Ultrasonic scaling with 0.12% chlorhexidine (10 subjects). At the baseline one blood agar plate was kept for 10 minutes in the fumigated chamber before ultrasonic scaling, thereafter three blood agar plates were kept at a distance of 0.4 meters away on either side of the patient and 2 meters behind the patient's mouth during ultrasonic scaling. Blood agar plates were kept for gravitometric settling of dental aerosols.

RESULTS

At baseline, no significant numbers of Colony-Forming Units (CFU) were detected. It is found that Group 3 (chlorhexidine gluconate) showed effective CFU reduction (27.17 ±12.5 CFU) when compared to distilled water (124.5 ± 30.08 CFU) and povidone iodine (60.43 ± 33.33 CFU). More CFU were found on blood agar plates which were kept on right side in all the three groups. The results obtained were statistically significant (p< 0.001).

CONCLUSION

Chlorhexidine gluconate is more effective in reducing dental aerosols when compared to povidone iodine and distilled water. Povidone iodine showed better CFU reduction when compared with distilled water. Hence, chlorhexidine or povidone iodine can also be used as an ultrasonic liquid coolant for reducing the number of dental aerosols during ultrasonic scaling.

Effect of 0.12% chlorhexidine in reducing microorganisms found in aerosol used for dental prophylaxis of patients submitted to fixed orthodontic treatment

Objective

This study aimed at assessing, in vivo, whether the prior use of 0.12% chlorhexidine as mouthwash would decrease air contamination caused by aerosolized sodium bicarbonate during dental prophylaxis. The study was conducted with 23 patients aged between 10 and 40 years old who were randomly selected and undergoing fixed orthodontic treatment.

Methods

The study was divided into two phases (T₁ and T₂) with a 30-day interval in between. In both phases, dental prophylaxis was performed with aerosolized sodium bicarbonate jetted to the upper and lower arches for 4 minutes. In T₁, 10 minutes before the prophylaxis procedure, the participants used distilled water as mouthwash for one minute; whereas in T₂, mouthwash was performed with 0.12% chlorhexidine. Microbial samples were collected in BHI agar plates for microbiological analysis. Two dishes were positioned on the clinician (10 cm from the mouth) and a third one at 15 cm from the patient's mouth. The samples were incubated for 48 hours at 37°C. Results were expressed in colony-forming units (CFU).

Results

Statistical analysis carried out by means of Student's t test, as well as Wilconxon and Kruskal-Wallis tests revealed that the prior use of 0.12% chlorhexidine as mouthwash significantly reduced CFU in the three positions studied (P < 0.001).

Conclusion

The prior use of 0.12% chlorhexidine as mouthwash significantly reduced contamination caused by aerosolized sodium bicarbonate during dental prophylaxis in the orthodontic clinic.

Aerosols how dangerous they are in clinical practice

BACKGROUND AND OBJECTIVES

The purpose of the present study was to determine the microbial atmospheric contamination during initial periodontal treatment using a modern piezoelectric scaler and to evaluate the efficacy of two commercially available mouth rinses (0.2% Chlorhexidine mouth rinse and Listerine) in reducing bacterial contamination when used as a pre-procedural rinse, with and without high volume evacuation (Aerosol reduction device).

MATERIALS AND METHODS

Subjects for the study were selected from the outpatient Department of Periodontics, Sri Siddhartha Dental College and Hospital, Tumkur, India. Total 60 patients were taken for the study and on the basis of inclusion and exclusion criteria's they were divided into three groups. The sampling was carried out in two stages before and after implementing a set protocol. Total duration of study was four months.

MICROBIOLOGICAL EVALUATION

The samples (blood agar plates) were transported immediately to the Department of Microbiology, Sri Siddhartha Medical College, Tumkur for: Identification of microorganisms as per standard procedures (Gram stain, Biochemical Test, Species Identification).Counting the number of colonies formed on blood agar plates using colony counter unit.

RESULTS

Out of all the three pre-procedural rinses 0.2% w/v Chlorhexidine is the best in reducing aerobic bacteria (CFU) followed by Listerine and then Water.

CONCLUSION

The following conclusion was drawn that the use of pre-procedural rinses along with the use of high volume suction apparatus significantly reduced the aerosol contamination and hence chances of cross-infection in the dental units.

The effectiveness of a pre-procedural mouthrinse in reducing bacteria on radiographic phosphor plates

Purpose

This study assessed the effectiveness of three antimicrobial mouthrinses in reducing microbial growth on photostimulable phosphor (PSP) plates.

Materials and Methods

Prior to performing a full-mouth radiographic survey (FMX), subjects were asked to rinse with one of the three test rinses (Listerine®, Decapinol®, or chlorhexidine oral rinse 0.12%) or to refrain from rinsing. Four PSP plates were sampled from each FMX through collection into sterile containers upon exiting the scanner. Flame-sterilized forceps were used to transfer the PSP plates onto blood agar plates (5% sheep blood agar). The blood agar plates were incubated at 37℃ for up to 72 h. An environmental control blood agar plate was incubated with each batch. Additionally, for control, 25 gas-sterilized PSP plates were plated onto blood agar and analyzed.

Results

The mean number of bacterial colonies per plate was the lowest in the chlorhexidine group, followed by the Decapinol, Listerine, and the no rinse negative control groups. Only the chlorhexidine and Listerine groups were significantly different (p=0.005). No growth was observed for the 25 gas-sterilized control plates or the environmental control blood agar plates.

Conclusion

The mean number of bacterial colonies was the lowest in the chlorhexidine group, followed by the Decapinol, Listerine, and the no rinse groups. Nonetheless, a statistically significant difference was found only in the case of Listerine. Additional research is needed to test whether a higher concentration (0.2%) or longer exposure period (two consecutive 30 s rinse periods) would be helpful in reducing PSP plate contamination further with chlorhexidine.

Compare the effcacy of two commercially available mouthrinses in reducing viable bacterial count in dental aerosol produced during ultrasonic scaling when used as a preprocedural rinse

AIM

To evaluate and compare the effcacy of preprocedural mouthrinses (chlorhexidine digluconate and tea tree oil) in reducing microbial content of aerosol product during ultrasonic scaling procedures by viable bacterial count.

SETTINGS AND DESIGN

It was a randomized single blind, placebo-controlled parallel group study.

MATERIALS AND METHODS

Sixty subjects were randomly assigned to rinse 10 ml of any one of the mouthrinses (chlorhexidine digluconate or tea tree oil or distilled water). Ultrasonic scaling was done for a period of 10 minutes in presence of trypticase soy agar plates placed at standardized distance. Plates were then sent for microbiological evaluation for the aerosol produced.

RESULTS

This study showed that all the antiseptic mouthwashes signifcantly reduced the bacterial colony forming units (CFUs) in aerosol samples. Chlorhexidine rinses were found to be superior to tea tree when used preprocedurally in reducing aerolized bacteria.

CONCLUSION

This study advocates preprocedural dural rinsing with an effective antimicrobial mouthrinse during any dental treatment which generates aerosols, reduces the risk of cross-contamination with infectious agents in the dental operatory.

CLINICAL SIGNIFICANCE

The aerolization of oral microbes occurring during dental procedures can potentially result in cross-contamination in the dental operatory and transmission of infectious agents to both dental professionals and patient. It is reasonable to assume therefore, that any stratagem for reducing the viable bacterial content of these aerosols could lower the risk of cross-contamination.

2013 AAHA dental care guidelines for dogs and cats

Veterinary dentistry is constantly progressing. The purpose of this document is to provide guidelines for the practice of companion animal dentistry for the veterinary profession. Dental care is necessary to provide optimum health and optimize quality of life. Untreated diseases of the oral cavity are painful and can contribute to local and systemic diseases. This article includes guidelines for preventive oral health care, client communication, evaluation, dental cleaning, and treatment. In addition, materials and equipment necessary to perform a medically appropriate procedure are described.

Efficacy of 0.2% tempered chlorhexidine as a pre-procedural mouth rinse: A clinical study

OBJECTIVE

Our objective was to determine the efficacy of pre-procedural rinsing with chlorhexidine in reducing bacterial aerosol contamination during use of ultrasonic scaler and comparing the efficacy of water, non-tempered chlorhexidine and tempered chlorhexidine in reducing bacterial count in aerosols when used as a pre-procedural rinse.

MATERIALS AND METHODS

The study was designed to include 30 systemically healthy patients in different age groups. The patients were divided randomly into 3 groups (I, II, III) of 10 patients each to be administered with sterile water, non tempered chlorhexidine and tempered chlorhexidine, respectively, as a pre-procedural rinse. The aerosol produced by the ultrasonic unit was collected at 3° clock, 6° clock and 12° clock positions on blood agar plates within a range of 4 feet in all the three groups. The blood agar plates were incubated for 48 hours and the total number of colony forming units (CFUs) were counted and statistically analyzed.

RESULTS

The results showed that CFU in group III and group II were significantly reduced when compared to group I with F=1084.92, P<0.001 (ANOVA). Also, CFU in group III was significantly reduced when compared to group II with P<0.001.

CONCLUSIONS

Pre-procedural rinse can significantly reduce the viable microbial content of dental aerosols and tempered chlorhexidine was more effective than non-tempered chlorhexidine.

A study to evaluate and compare the efficacy of preprocedural mouthrinsing and high volume evacuator attachment alone and in combination in reducing the amount of viable aerosols produced during ultrasonic scaling procedure

BACKGROUND AND OBJECTIVES

In recent years, ultrasonics has gained prime importance and is considered a valuable tool in the dentist's armamentarium. Studies have confirmed that an aerosolized bacterial contamination is produced during the use of ultrasonic scalers.

AIM

To evaluate and compare the efficacy of preprocedural mouthrinsing using a bis-biguanide (chlorhexidine gluconate 0.2%) and high volume evacuator attachment alone and in combination in reducing the amount of viable aerosols produced during ultrasonic scaling procedure.

MATERIALS AND METHODS

A total 90 subjects were assigned to group I (who rinsed with 0.2% chlorhexidine gluconate prior to scaling), group II (high volume evacuator attachment was used during ultrasonic scaling) and group III (who rinsed with 0.2% chlorhexidine gluconate prior to scaling and in whom high volume evacuator attachment was used during ultrasonic scaling). Control group consisted of subject's whose mouth was scaled using a piezoelectric ultrasonic scaler without preprocedural rinsing or high volume suction. Aerosol samples were collected using blood agar plates. The blood agar plates containing the aerosol sample were taken to the microbiology department as soon as the sampling was over and were subjected to aerobic culturing.

RESULTS

The values obtained showed that all the three groups were effective in reducing the mean colony forming units (CFUs).

CONCLUSION

The results of this study showed that preprocedural rinse and high volume suction were effective when used alone as well as together in reducing the microbial load of the aerosols produced during ultrasonic scaling. There was a significant reduction in the number of CFUs in aerosol samples obtained.

Efficacy of pre-procedural rinsing in reducing aerosol contamination during dental procedures

Our objective was to determine the efficacy of pre-procedural rinsing with chlorhexidine in reducing bacterial aerosol contamination during use of ultrasonic scaler and high speed air turbine handpiece. Twenty patients, ten each for the two groups who were found to satisfy the inclusion criteria were selected for the study. Four predesignated locations of the dental clinic were chosen to be evaluated for each patient using blood agar plates. Aerosols were collected during treatment procedures for control and experimental quadrants. Results showed that a regimen of 30-seconds pre-procedural rinsing with 0.12% chlorhexidine gluconate before dental procedures consistently reduced colony-forming units than without rinsing due to the ability of antiseptic mouthwash to inhibit microbial growth. There was more aerosol contamination during scaling procedures than during the use of a high speed air turbine handpiece. The conclusion is that chlorhexidine is an effective primary measure in reducing aerosol cross-contamination when using dental devices in a dental set up.

Measurement of particle concentrations in a dental office

Particles in a dental office can be generated by a number of instruments, such as air-turbine handpieces, low-speed handpieces, ultrasonic scalers, bicarbonate polishers, polishing cups, as well as drilling and air sprays inside the oral cavity. This study examined the generation of particles during dental drilling and measured particle size, mass, and trace elements. The air sampling techniques included both continuous and integrated methods. The following particle continuous measurements were taken every minute: (1) size-selective particle number concentration (Climet); (2) total particle number concentration (PTRAK), and; (3) particle mass concentration (DustTrak). Integrated particle samples were collected for about 5 h on each of five sampling days, using a PM(2.5) sampler (ChemComb) for elemental/organic carbon analysis, and a PM(10) sampler (Harvard Impactor) for mass and elemental analyses. There was strong evidence that these procedures result in particle concentrations above background. The dental procedures produced number concentrations of relatively small particles (<0.5 microm) that were much higher than concentrations produced for the relatively larger particles (>0.5 microm). Also, these dental procedures caused significant elevation above background of certain trace elements (measured by X-ray fluorescence) but did not cause any elevation of elemental carbon (measured by thermal optical reflectance). Dental drilling procedures aerosolize saliva and products of drilling, producing particles small enough to penetrate deep into the lungs. The potential health impacts of the exposure of dental personnel to such particles need to be evaluated. Increased ventilation and personal breathing protection could be used to minimize harmful effects.

Occupational hazards in orthodontics: A review of risks and associated pathology

The purpose of this article was to review the occupational hazards related to the practice of orthodontics. A systematic approach was used to include all risks involved in an orthodontic practice. The classification of hazards was based on major sources of risks by system or tissue and by orthodontic office area (dental chair, laboratory, sterilization area, x-ray developing area). Potentially hazardous factors relate to the general practice setting; to specific materials and tools that expose the operator to vision and hearing risks; to chemical substances with known allergenic, toxic, or irritating actions; to increased microbial counts and silica particles of the aerosols produced during debonding; to ergonomic considerations that might have an impact on the provider's muscoleskeletal system; and to psychological stress with proven undesirable sequelae. The identification and elimination of these risk factors should be incorporated into a standard practice management program as an integral part of orthodontic education. Professional organizations can also assist in informing practitioners of potential hazards and methods to deal with them.

Bacterial aerosols in dental practice - a potential hospital infection problem?

Aerosols containing microbes from the oral cavity of the patient are created when using modern high-speed rotating instruments in restorative dentistry. How far these aerosols spread and what level of contamination they cause in the dental surgery has become a growing concern as the number of patients with oro-nasal meticillin-resistant Staphylococcus aureus colonization has increased. The present study aimed to determine how far airborne bacteria spread during dental treatment, and the level of contamination. Fall out samples were collected on blood agar plates placed in six different sectors, 0.5-2m from the patient. Restorative dentistry fallout samples (N=72) were collected from rooms (N=6) where high-speed rotating instruments were used, and control samples (N=24) were collected from rooms (N=4) used for periodontal and orthodontic treatment where rotating and ultrasonic instruments were not used. The collection times were 1.5 and 3 h. In addition, samples were taken from facial masks of personnel and from surfaces in the rooms before and after disinfection. After 48 h of incubation at 37 degrees C, colonies were counted and classified by Gram stain. The results showed significant contamination of the room at all distances sampled when high-speed instruments were used (mean 970 colony-forming units/m2/h). The bacterial density was found to be higher in the more remote sampling points. Gram-positive cocci, namely viridans streptococci and staphylococci, were the most common findings. The area that becomes contaminated during dental procedures is far larger than previously thought and practically encompasses the whole room. These results emphasize the need for developing new means for preventing microbial aerosols in dentistry and protection of all items stored temporarily on work surfaces. This is especially important when treating generally ill or immunocompromised patients at dental surgeries in hospital environments.