Genomic identification and quantification of microbial species adhering to toothbrush bristles after disinfection: A cross-over study

In Vitro Efficacy of Domestic Techniques for Disinfection of Toothbrushes Contaminated With Enterococcus faecalis

Introduction: Oral hygiene education for patients is fundamental in preventive-promotional dentistry. The disinfection of toothbrushes (TBs) must be integrated into this context due to their proximity to contaminant sources that make them vulnerable to cross infection in homes. The objective of this study was to compare the efficacy of domestic techniques for disinfection of TBs. Materials and Methods: We performed an in vitro study of 76 TBs contaminated with Enterococcus faecalis (Ef) ATCC 29212 subjected to different disinfection protocols: G1. Distilled water (DW; negative control; n = 8), G2. Dimethylsulfoxide (DMSO)10% (negative control; n = 8), G3. Chlorhexidine (CHX) 0.12% (positive control; n = 15), G4. 100% white vinegar (WV; n = 15), G5. Microwave (MW) at 700 W (n = 15), and G6. 200 mg/mL of certified alcoholic extract of purple garlic (GARLIC) from Arequipa (Allium sativum L; n = 15). Bacterial count was assessed by colony-forming units (CFU/mL) categorized as contamination: low (<30), medium (30-300), and high (>300). The Kruskal-Wallis test with post hoc pairs was used at a significance level of p < 0.05. Results: Efficacy against Ef showed highly significant differences between groups (p < 0.001) with lower median CFU/mL in G3 and G4 (Me = 0 [IQR (interquartile range) = 0]: low) and G5 (Me = 6000 [IQR = 45,000]: low/medium) versus negative controls (Me = 378,500 and 5,020,000 [IQR = 4,605,000 and 6,760,000]: medium/high; p ≤ 0.019). The counts of the G5 were not statistically different than G3, G4, and G6 (p > 0.06). The G6 (Me = 1,510,000 [IQR = 590,000]: medium) was inferior to G3 and G4 (p < 0.001), but similar to both negative control groups (p > 0.999). Conclusions: Disinfection of TBs with CHX, WV, and MWs produces a significant effective reduction in the count of Ef.

Manual toothbrushes, self-toothbrushing, and replacement duration to remove dental plaque and improve gingival health: A scoping review from recent research

OBJECTIVE

To investigate characteristics of manual toothbrushes, self-toothbrushing methods, and replacement duration of manual toothbrushes that effectively remove dental plaque, reduce gingivitis, and promote gingival health.

STUDY DATA AND SOURCES

PubMed-MEDLINE, Scopus and Central Register Cochrane of Controlled trials (CENTRAL) were searched for randomized control trials (RCTs) from 01 January 2018 to 12 December 2023. Articles were subjected for including participants aged six years and older with a study duration of at least four weeks to investigate the efficacy of manual toothbrushes used self-toothbrushing. To investigate the appropriate time to replace manual toothbrushes, this study was focused on the physical properties of the bristles and changes in the microorganisms present in the bristles over time.

STUDY SELECTION

Of 1520 retrieved articles, 26 studies were included after screening. The total number of manual toothbrushes was 40 and 5 kinds of self-toothbrushing techniques were selected in the review. 4 studies investigated the changes the physical properties bristles of manual toothbrushes.

CONCLUSIONS

Among manual toothbrushes, the cross-angle and indicator bristles were found to significantly improve dental plaque index and gingival condition. Most toothbrushes with soft bristles had a trend of superior dental plaque removal and gingivitis improvement efficacy. Toothbrush with end-round shape bristles tip has tended to reduce the dental plaque and gingival index scores. Studies reported that brushing twice a day for at least two minutes using the Bass method had a positive effect on the dental plaque and gingival index. Further research is required to investigate the relationships between property physical bristle and clinical intraoral indices to clarify the replacement duration of manual toothbrushes.

CLINICAL SIGNIFICANCE

The findings of this study could guide people's daily self-brushing habits, thereby aiding the prevention of periodontal disease. Moreover, our findings suggest the need for strategic clinical trial designs to verify the ideal timing to replace manual toothbrushes.

Bacterial decontamination of toothbrushes by immersion in a mouthwash containing 0.05% chlorhexidine and 0.05% cetylpyridinium chloride: A randomized controlled trial

OBJECTIVE

Toothbrushes are colonized by microorganisms, implying a risk of infection. That risk can be reduced by decreasing the microbial contamination of the filaments. Therefore, this study aimed to determine the antiseptic efficacy of a 0.05% chlorhexidine + 0.05% cetylpyridinium chloride mouthwash on toothbrushes.

METHODS

A total of twelve toothbrushes used three times/day for 14 days by orally and systemically healthy people were randomly split into two groups, and their heads were immersed for 2 h in PBS (control) or Perio·Aid Active Control (treatment). The microorganisms were recovered, and their number was calculated by culture, quantitative PCR, and viability PCR. Statistical differences were first assessed with a two-way mixed ANOVA and subsequently with Student's t-test.

RESULTS

The results showed no statistical differences in the total number of cells for the treatment (mean ± CI95% of 7.27 ± 1.09 log₁₀ bacteria/ml) and the control (7.62 ± 0.64 log₁₀ bacteria/ml) groups, but a significantly lower number of live cells in the treatment group (4.58 ± 0.61 log₁₀ viable bacteria/ml and 2.15 ± 1.42 log₁₀ cfu/ml) than in the control group (6.49 ± 1.39 log₁₀ viable bacteria/ml and 5.04 ± 0.93 log₁₀ cfu/ml).

CONCLUSIONS

Based on our findings, sanitization of toothbrushes with this mouthwash reduces the number of live microorganisms adhered to the filaments. Such decrease of the bacterial load could include bacteria from the oral cavity, from the environment, and from nearby toothbrushes since the quantification was not limited to any bacterial taxon.

The role of toothbrush in the transmission of corona- and influenza viruses - results of an in vitro study

Objectives

The aim of this in vitro study was to investigate viruses’ stabilities on manual toothbrushes using feline coronavirus (FeCoV) as representative of coronaviruses and an Avian influenza A virus H1N1 for influenza viruses.

Material and methods

Two viruses, FeCoV (Strain Munich; titer 107.5 TCID50/ml) and H1N1 (RE 230/90; titer 106.5 TCID50/ml), were used in this study. Manual toothbrushes were disassembled into bristles, bristle fixation, and back of the toothbrush head, contaminated with the viruses and air-dried for 24 h. In a second experiment, whole toothbrush heads were contaminated, rinsed with water (5 ml for 15 s) and then air-dried.

Results

For FeCoV, immediately after contamination, the following average titers were recovered: fixation: 10^6.41, back of head: 10^6.81 and bristles: 10^6.63 TCID₅₀/ml. Following air-drying of 12 (fixation) and 24 h, titers of ≤ 10^2.5, 10^3.75, and 10^2.72 TCID₅₀/ml were found in the respective groups, with a detection limit of 10^2.5 TCID₅₀/ml. For H1N1, immediately after contamination, the following average titers could be recovered: fixation: 10^5.53, back of head: 10^5.97 and bristles: 10^5.75 TCID₅₀/ml. Following air-drying of 8 (fixation) and 24 h, titers were ≤ 10^2.5, 10^3.63, and 10^3.53 TCID₅₀/ml in the respective group, again with 10^2.5 TCID₅₀/ml being the detection limit. In case of water rinse, no infectious virus could be recovered after 12 h.

Conclusion

Viral load of both viruses is reduced by air-drying, especially following water rinsing.

Clinical relevance

The toothbrush itself plays an insignificant role in the self-transmission of coronavirus and influenza virus.

Contamination of antimicrobial-resistant bacteria on toothbrushes used with mechanically ventilated patients: A cross sectional study

OBJECTIVE

The purpose of this study was to determine pathogenic and antimicrobial-resistant bacteria on used toothbrushes of mechanically ventilated patients.

RESEARCH METHODOLOGY

A cross-sectional study was conducted by collecting toothbrushes used with mechanically ventilated patients. The total bacterial count on each toothbrush was assessed by culturing on Trypticase soy agar (TSA). Gram stain and biochemical testing were used to identify bacterial species. Antibiotic susceptibility of pathogenic bacteria was assessed by the Kirby-Bauer disk diffusion method.

RESULTS

Thirty-five toothbrushes (97%) had bacterial contamination, 27 toothbrushes had at least two bacterial species, and 13 toothbrushes harboured antimicrobial-resistant bacteria. The most commonly isolated bacteria were Klebsiella spp. (21%), followed by Acinetobacter baumannii (18%). Five isolates of A. baumannii, six isolates of K. pneumoniae, and two isolates of Enterobacter cloacae were multidrug-resistant (MDR) strains. Four isolates of K. pneumoniae were identified as extended-spectrum beta-lactamase (ESBL) producing strains, and two isolates of P. aeruginosa were extensively drug-resistant (XDR). The average total bacterial count was 10⁴-10⁵ CFU/toothbrush head.

CONCLUSIONS

Antimicrobial-resistant bacteria were detected on toothbrushes. Therefore, practice of toothbrush care should be reconsidered in associated to maintaining the oral hygiene of mechanically ventilated patients to prevent ventilator-associated pneumonia (VAP).

Nano-enabled, antimicrobial toothbrushes - How physical and chemical properties relate to antibacterial capabilities

Over the past two decades, Ag and Zn nanoparticles have been integrated into various consumer products as a biocide. While some nano-enabled consumer products have been shown to have antibacterial properties, their antibacterial efficacy as well as the human and environmental health outcomes are not fully known. In this study, we examine a nanoparticle-enabled product that also serves as a conduit for human exposure to bacteria: toothbrushes. We utilize a combination of chemical analyses, laboratory experiments, and microscopy to characterize the nano-enabled toothbrush bristles. Our analysis showed the majority of measured Ag and Zn particles ranged from approximately 50 to 100 nm in size and were located on the surface and within bristles. During simulated brushing, antimicrobial bristles released both Ag and Zn, the majority of which was released in particulate form. While our results demonstrate that antimicrobial bristles have enhanced bactericidal properties compared to control samples, we also show that the surface topography influences nanoparticle retention, microbial adhesion, and bactericidal activity. We thus conclude that Ag or Zn content alone is insufficient to predict antimicrobial properties, which are further governed by the bioavailability of Ag or Zn at the bristle surface.

ED approach to electrical toothbrush associated hand injury, a unique case of non-oropharyngeal injury

Puncture wounds are common injuries treated in the emergency department (ED). Prior studies have shown that toothbrushes are common reservoirs for oral flora, especially in regions near the head of the toothbrush near the bristles. ED providers must be aware of the danger associated with bacterial contamination of the associated wound and should be familiar with different pathogens and options for treatment. We present a unique case of a 30-year-old male with non-intraoral injury who presented to the ED after puncturing his left palm with the metal post of an electric toothbrush.

Is pomegranate peels infusion effective for disinfection of toothbrushes?

Abstract Introduction Methods of decontamination or sanitization of toothbrushes have been questioned. Objective This study assessed the effectiveness of pomegranate peels infusion as a disinfectant of toothbrushes against Streptococcus mutans. Material and method A sample of 16 schoolchildren aged between 7 and 9 years performed brushing 5 days/week, with a careful brushing once a day. After each day of brushing, the toothbrushes were washed and sprayed with one disinfectant solution. This procedure was repeated for 4 weeks using one of the different solutions per week: distilled water (G1; negative control), pomegranate (Punica granatum Linn) peels infusion (G2), 1% sodium hypochlorite (G3) and 0.12% chlorhexidine digluconate (G4). After the fifth day, toothbrushes were collected for laboratory analysis. Toothbrushes heads were subjected to agitation in saline dilution of 10–1, 10–2,10–3, and 25 μL of each dilution were seeded in mitis salivarius agar culture medium for S. mutans colony-forming unit (CFU) counting. One calibrated examiner (Kappa = 0.91) performed the CFU (mL–1 × 104) counts. Kruskal-Wallis and Dunn Multiple Comparison tests were used at a significance level of 5%. Result G1 presented the highest number of CFU (3.9 ± 8.4), followed by G2 (3.2 ± 4.0). No S. mutans growth was observed in G3 and G4. There was no statistically significant difference between G1 and G2 and between G3 and G4 (p>0.05). Conclusion Pomegranate infusion was completely ineffective for the disinfection of toothbrushes against S. mutans when compared with 1% sodium hypochlorite and 0.12% chlorhexidine digluconate solutions.