1
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Moran SP, Rosier BT, Henriquez FL, Burleigh MC. The effects of nitrate on the oral microbiome: a systematic review investigating prebiotic potential. J Oral Microbiol 2024; 16:2322228. [PMID: 38420038 PMCID: PMC10901185 DOI: 10.1080/20002297.2024.2322228] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2023] [Accepted: 02/15/2024] [Indexed: 03/02/2024] Open
Abstract
Background Nitrate (NO3-) has been suggested as a prebiotic for oral health. Evidence indicates dietary nitrate and nitrate supplements can increase the proportion of bacterial genera associated with positive oral health whilst reducing bacteria implicated in oral disease(s). In contrast, chlorhexidine-containing mouthwashes, which are commonly used to treat oral infections, promote dysbiosis of the natural microflora and may induce antimicrobial resistance. Methods A systematic review of the literature was undertaken, surrounding the effects of nitrate on the oral microbiota. Results Overall, n = 12 in vivo and in vitro studies found acute and chronic nitrate exposure increased (representatives of) health-associated Neisseria and Rothia (67% and 58% of studies, respectively) whilst reducing periodontal disease-associated Prevotella (33%). Additionally, caries-associated Veillonella and Streptococcus decreased (25% for both genera). Nitrate also altered oral microbiome metabolism, causing an increase in pH levels (n = 5), which is beneficial to limit caries development. Secondary findings highlighted the benefits of nitrate for systemic health (n = 5). Conclusions More clinical trials are required to confirm the impact of nitrate on oral communities. However, these findings support the hypothesis that nitrate could be used as an oral health prebiotic. Future studies should investigate whether chlorhexidine-containing mouthwashes could be replaced or complemented by a nitrate-rich diet or nitrate supplementation.
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Affiliation(s)
- Siobhan P. Moran
- School of Health and Life Sciences, University of the West of Scotland, Blantyre, UK
| | - Bob T. Rosier
- Department of Health and Genomics, Center for Advanced Research in Public Health, FISABIO Foundation, Valencia, Spain
| | - Fiona L. Henriquez
- School of Health and Life Sciences, University of the West of Scotland, Blantyre, UK
| | - Mia C. Burleigh
- School of Health and Life Sciences, University of the West of Scotland, Blantyre, UK
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2
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Brookes Z, Teoh L, Cieplik F, Kumar P. Mouthwash Effects on the Oral Microbiome: Are They Good, Bad, or Balanced? Int Dent J 2023; 73 Suppl 2:S74-S81. [PMID: 37867065 PMCID: PMC10690560 DOI: 10.1016/j.identj.2023.08.010] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Accepted: 08/21/2023] [Indexed: 10/24/2023] Open
Abstract
This narrative review describes the oral microbiome, and its role in oral health and disease, before considering the impact of commonly used over-the-counter (OTC) mouthwashes on oral bacteria, viruses, bacteriophages, and fungi that make up these microbial communities in different niches of the mouth. Whilst certain mouthwashes have proven antimicrobial actions and clinical effectiveness supported by robust evidence, this review reports more recent metagenomics evidence, suggesting that mouthwashes such as chlorhexidine may cause "dysbiosis," whereby certain species of bacteria are killed, leaving others, sometimes unwanted, to predominate. There is little known about the effects of mouthwashes on fungi and viruses in the context of the oral microbiome (virome) in vivo, despite evidence that they "kill" certain viral pathogens ex vivo. Evidence for mouthwashes, much like antibiotics, is also emerging with regards to antimicrobial resistance, and this should further be considered in the context of their widespread use by clinicians and patients. Therefore, considering the potential of currently available OTC mouthwashes to alter the oral microbiome, this article finally proposes that the ideal mouthwash, whilst combatting oral disease, should "balance" antimicrobial communities, especially those associated with health. Which antimicrobial mouthwash best fits this ideal remains uncertain.
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Affiliation(s)
- Zoë Brookes
- Peninsula Dental School, Plymouth University, Plymouth, UK.
| | - Leanne Teoh
- Melbourne Dental School, The University of Melbourne, Carlton, Victoria, Australia
| | - Fabian Cieplik
- Department of Conservative Dentistry and Periodontology, University Hospital Regensburg, Regensburg, Germany
| | - Purnima Kumar
- Department of Periodontics and Oral Medicine, School of Dentistry, University of Michigan, Ann Arbor, USA
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3
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Ardila CM, Bedoya-García JA. Bacterial resistance to antiseptics used in dentistry: A systematic scoping review of randomized clinical trials. Int J Dent Hyg 2023; 21:141-148. [PMID: 36269218 DOI: 10.1111/idh.12629] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Revised: 08/29/2022] [Accepted: 10/19/2022] [Indexed: 01/12/2023]
Abstract
OBJECTIVES To evaluate the prevalence and proportions of bacteria resistant to antiseptics used in dentistry. METHODS A review of randomized clinical trials (RCTs) was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-analyses extension for scoping reviews involving different databases. MeSH terms and keywords were provided to examine only RCTs with antiseptic-resistant results. RESULTS Five RCTs were included. These investigations analysed 442 patients. Concerning the prevalence and proportion of species resistant to antiseptics, it was found that the chlorhexidine group showed a statistically significant increase in Streptococcus mutans and Lactobacillus acidophilus counts indicating bacterial resistance (p < 0.001). Moreover, Veillonella species showed resistance to triclosan at the commencement and during the RCTs, and a slight increase in the proportion of resistant strains was observed. Porphyromonas gingivalis, Staphylococcus aureus, and Pseudomonas aeruginosa did not show resistance to cetylpyridinium chloride. Similarly, it was no observed resistance to medicinal herbal plant formulations. CONCLUSIONS Resistance of S. mutans and L. acidophilus to chlorhexidine was observed, this resistance increased during the follow-up period. Similarly, although in a slight proportion, an increase in the resistance of Veillonella spp. to triclosan during the study period was also described. No microorganisms resistance was observed to any of the other antiseptics studied.
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Affiliation(s)
- Carlos M Ardila
- Universidad de Antioquia U de A, Medellín, Colombia.,Biomedical Stomatology Research Group, Universidad de Antioquia U de A, Medellín, Colombia
| | - Jader Alexander Bedoya-García
- Universidad de Antioquia U de A, Medellín, Colombia.,Biomedical Stomatology Research Group, Universidad de Antioquia U de A, Medellín, Colombia
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4
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Yang Z, Cai T, Li Y, Jiang D, Luo J, Zhou Z. Effects of topical fluoride application on oral microbiota in young children with severe dental caries. Front Cell Infect Microbiol 2023; 13:1104343. [PMID: 36960045 PMCID: PMC10028198 DOI: 10.3389/fcimb.2023.1104343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 02/17/2023] [Indexed: 03/09/2023] Open
Abstract
While the effect of fluoride on severe early childhood caries (S-ECC) is clear, knowledge of how it influences the oral microbiota and the consequential effects on oral health is limited. In this cohort study, we investigated the changes introduced in the oral ecosystem before and after using fluoride varnish in 54- to 66-month-old individuals (n=90: 18 children were sampled at 5 different time points). 16S rDNA was amplified from bacterial samples using polymerase chain reaction, and high-throughput sequencing was performed using Illumina MiSeq platforms. Many pronounced microbial changes were related to the effects of fluoride varnishing. The health-associated Bacteroides and Uncultured_bacterium_f_Enterobacteriaceae were enriched in the saliva microbiome following treatment with fluoride varnishing. Co-occurrence network analysis of the dominant genera showed that different groups clearly showed different bacterial correlations. The PICRUSt algorithm was used to predict the function of the microbial communities from saliva samples. The results showed that starch and sucrose metabolism was greater after fluoride use. BugBase was used to determine phenotypes present in microbial community samples. The results showed that Haemophilus and Neisseria (phylum Proteobacteria) was greater before fluoride use. We conclude that the changes in oral microbiology play a role in fluoride prevention of S-ECC.
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Affiliation(s)
- Zhengyan Yang
- Department of Preventive Dentistry, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Biomedical Engineering of Higher Education, Department of Preventive Dentistry, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
| | - Ting Cai
- Department of Preventive Dentistry, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Biomedical Engineering of Higher Education, Department of Preventive Dentistry, Chongqing, China
| | - Yueheng Li
- Department of Preventive Dentistry, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Biomedical Engineering of Higher Education, Department of Preventive Dentistry, Chongqing, China
- Chongqing Key Laboratory of Oral Diseases and Biomedical Sciences, Chongqing, China
| | - Dan Jiang
- Chongqing Key Laboratory of Oral Biomedical Engineering of Higher Education, Department of Preventive Dentistry, Chongqing, China
| | - Jun Luo
- Department of Preventive Dentistry, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Biomedical Engineering of Higher Education, Department of Preventive Dentistry, Chongqing, China
- *Correspondence: Jun Luo, ; Zhi Zhou,
| | - Zhi Zhou
- Department of Preventive Dentistry, Stomatological Hospital of Chongqing Medical University, Chongqing, China
- Chongqing Key Laboratory of Oral Biomedical Engineering of Higher Education, Department of Preventive Dentistry, Chongqing, China
- *Correspondence: Jun Luo, ; Zhi Zhou,
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5
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Müller-Heupt LK, Vierengel N, Groß J, Opatz T, Deschner J, von Loewenich FD. Antimicrobial Activity of Eucalyptus globulus, Azadirachta indica, Glycyrrhiza glabra, Rheum palmatum Extracts and Rhein against Porphyromonas gingivalis. Antibiotics (Basel) 2022; 11:antibiotics11020186. [PMID: 35203789 PMCID: PMC8868162 DOI: 10.3390/antibiotics11020186] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2021] [Revised: 01/20/2022] [Accepted: 01/29/2022] [Indexed: 01/27/2023] Open
Abstract
Novel plant-derived antimicrobials are of interest in dentistry, especially in the treatment of periodontitis, since the use of established substances is associated with side effects and concerns of antimicrobial resistance have been raised. Thus, the present study was performed to quantify the antimicrobial efficacy of crude plant extracts against Porphyromonas gingivalis, a pathogen associated with periodontitis. The minimal inhibitory concentrations (MICs) of Eucalyptus globulus leaf, Azadirachta indica leaf, Glycyrrhiza glabra root and Rheum palmatum root extracts were determined by broth microdilution for P. gingivalis ATCC 33277 according to CLSI (Clinical and Laboratory Standards Institute). The MICs for the E. globulus, A. indica and G. glabra extracts ranged from 64 mg/L to 1024 mg/L. The lowest MIC was determined for an ethanolic R. palmatum extract with 4 mg/L. The MIC for the anthraquinone rhein was also measured, as the antimicrobial activity of P. palmatum root extracts can be partially traced back to rhein. Rhein showed a remarkably low MIC of 0.125 mg/L. However, the major compounds of the R. palmatum root extract were not further separated and purified. In conclusion, R. palmatum root extracts should be further studied for the treatment of periodontitis.
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Affiliation(s)
- Lena Katharina Müller-Heupt
- Department of Oral and Maxillofacial Surgery, University Medical Center Mainz, Augustusplatz 2, D-55131 Mainz, Germany
- Correspondence:
| | - Nina Vierengel
- Department of Chemistry, Johannes Gutenberg-University, Duesbergweg 10–14, D-55128 Mainz, Germany; (N.V.); (J.G.); (T.O.)
| | - Jonathan Groß
- Department of Chemistry, Johannes Gutenberg-University, Duesbergweg 10–14, D-55128 Mainz, Germany; (N.V.); (J.G.); (T.O.)
| | - Till Opatz
- Department of Chemistry, Johannes Gutenberg-University, Duesbergweg 10–14, D-55128 Mainz, Germany; (N.V.); (J.G.); (T.O.)
| | - James Deschner
- Department of Periodontology and Operative Dentistry, University Medical Center Mainz, Augustusplatz 2, D-55131 Mainz, Germany;
| | - Friederike D. von Loewenich
- Department of Medical Microbiology and Hygiene, University of Mainz, Obere Zahlbacherstr. 67, D-55131 Mainz, Germany;
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6
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Steiger J, Braissant O, Waltimo T, Astasov-Frauenhoffer M. Efficacy of Experimental Mouth Rinses on Caries-Related Biofilms in vitro. FRONTIERS IN ORAL HEALTH 2022; 2:676028. [PMID: 35048021 PMCID: PMC8757722 DOI: 10.3389/froh.2021.676028] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 06/04/2021] [Indexed: 11/15/2022] Open
Abstract
This study assessed the efficacy of tin and Polyethylenglycol (PEG-3) tallow aminopropylamine in different concentrations on Streptococcus mutans (S. mutans) biofilms to establish a new screening process for different antimicrobial agents and to gain more information on the antibacterial effects of these agents on cariogenic biofilms. Isothermal microcalorimetry (IMC) was used to determine differences in two growth parameters: lag time and growth rate; additionally, reduction in active biofilms was calculated. Experimental mouth rinses with 400 and 800 ppm tin derived from stannous fluoride (SnF2) revealed results (43.4 and 49.9% active biofilm reduction, respectively) similar to meridol mouth rinse (400 ppm tin combined with 1,567 ppm PEG-3 tallow aminopropylamine; 55.3% active biofilm reduction) (p > 0.05), while no growth of S. mutans biofilms was detected during 72 h for samples treated with an experimental rinse containing 1,600 ppm tin (100% active biofilm reduction). Only the highest concentration (12,536 ppm) of rinses containing PEG-3 tallow aminopropylamine derived from amine fluoride (AmF) revealed comparable results to meridol (57.5% reduction in active biofilm). Lower concentrations of PEG-3 tallow aminopropylamine showed reductions of 16.9% for 3,134 ppm and 33.5% for 6,268 ppm. Maximum growth rate was significantly lower for all the samples containing SnF2 than for the samples containing control biofilms (p < 0.05); no differences were found between the control and all the PEG-3 tallow aminopropylamine (p > 0.05). The growth parameters showed high reproducibility rates within the treated groups of biofilms and for the controls; thus, the screening method provided reliable results.
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Affiliation(s)
- Josiana Steiger
- Clinic for Oral Health & Medicine, University Center for Dental Medicine Basel UZB University of Basel, Basel, Switzerland
| | - Olivier Braissant
- Department of Biomedical Engineering (DBE), Center of Biomechanics and Biocalorimetry, University of Basel, Allschwil, Switzerland
| | - Tuomas Waltimo
- Clinic for Oral Health & Medicine, University Center for Dental Medicine Basel UZB University of Basel, Basel, Switzerland
| | - Monika Astasov-Frauenhoffer
- Department Research, University Center for Dental Medicine Basel UZB University of Basel, Basel, Switzerland
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7
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Sequential Application of Calcium Phosphate and ε-Polylysine Show Antibacterial and Dentin Tubule Occluding Effects In Vitro. Int J Mol Sci 2021; 22:ijms221910681. [PMID: 34639022 PMCID: PMC8508875 DOI: 10.3390/ijms221910681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 09/25/2021] [Accepted: 09/27/2021] [Indexed: 11/23/2022] Open
Abstract
In this study, ε-polylysine and calcium phosphate precipitation (CPP) methods were employed to induce antibacterial effects and dentin tubule occlusion. Antibacterial effects of ε-polylysine were evaluated with broth dilution assay against P. gingivalis. CPP solution from MCPM, DCPD, and TTCP was prepared. Four concentrations of ε-polylysine(ε-PL) solutions (0.125%, 0.25%, 0.5%, 1%) were prepared. Dentin discs were prepared from recently extracted human third molars. Dentin discs were incubated with P. gingivalis (ATCC 33277) bacterial suspension (ca. 105 bacteria) containing Brain Heart Infusion medium supplemented with 0.1 g/mL Vitamin K, 0.5 mg/mL hemin, 0.4 g/mL L-cysteine in anaerobic jars (37 °C) for 7 days to allow for biofilm formation. P. g–infected dentin specimens were randomly divided into four groups: CPP + 0.125% ε-PL, CPP + 0.25% ε-PL, CPP + 0.5% ε-PL, CPP + 1% ε-PL. On each dentin specimen, CPP solution was applied followed by polylysine solution with microbrush and immersed in artificial saliva. Precipitate formation, antibacterial effects, and occlusion of dentinal tubules were characterized in vitro over up to 72 h using scanning electron microscopy. ε-PL showed 34.97% to 61.19% growth inhibition levels against P. gingivalis (P. g) after 24 h of incubation. On P. g-infected dentin specimens, DCPD + 0.25% ε-PL, and DCPD + 0.5% ε-PL groups showed complete bacterial inhibition and 78.6% and 98.1% dentin tubule occlusion, respectively (p < 0.001). The longitudinal analysis on fractured dentin samples in DCPD and TTCP groups revealed deeply penetrated hydroxyapatite-like crystal formations in dentinal tubules after 72 h of incubation in artificial saliva.
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8
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The influence of biofilm maturation on fluoride's anticaries efficacy. Clin Oral Investig 2021; 26:1269-1282. [PMID: 34328559 DOI: 10.1007/s00784-021-04100-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Accepted: 07/23/2021] [Indexed: 10/20/2022]
Abstract
OBJECTIVES (1) To explore the influence of biofilm maturation and timing of exposure on fluoride anticaries efficacy and (2) to explore biofilm recovery post-treatment. METHODS Bovine enamel specimens were utilized in a pH cycling model (28 subgroups [n = 18]). Each subgroup received different treatments [exposure]: sodium fluoride [NaF]; stannous fluoride [SnF2]; amine fluoride [AmF]; and de-ionized water [DIW], at a specific period: early: days 1-4; middle: days 3-6; and late: days 7-10. During non-exposure periods, pH cycling included DIW instead of fluorides. Objective 1: part 1 (cycling for 4, 6, or 10 days). Part 2 (cycling for 10 days). Objective 2: early exposure: three sample collection time points (immediate, 3 days, and 6 days post-treatment); middle exposure: two sample collection time points (immediate, 4 days post-treatment). The enamel and biofilm were analyzed ([surface microhardness; mineral loss; lesion depth]; [lactate dehydrogenase enzyme activity; exopolysaccharide amount; viability]). Data were analyzed using ANOVA (p = 0.05). RESULTS Objective 1: Early exposure to fluorides produced protective effects against lesion progression in surface microhardness and mineral loss, but not for lesion depth. Objective 2: Early exposure slowed the demineralization process. SnF2 and AmF were superior to NaF in reducing LDH and EPS values, regardless of exposure time. They also prevented biofilm recovery. CONCLUSION Earlier exposure to SnF2 and AmF may result in less tolerant biofilm. Early fluoride treatment may produce a protective effect against demineralization. SnF2 and AmF may be the choice to treat older biofilm and prevent biofilm recovery. CLINICAL RELEVANCE The study provides an understanding of biofilm-fluoride interaction with mature biofilm (e.g., hard-to-reach areas, orthodontic patients) and fluoride's sustainable effect hours/days after brushing.
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9
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Verspecht T, Van Holm W, Boon N, Bernaerts K, Daep CA, Masters JG, Zayed N, Quirynen M, Teughels W. Potential prebiotic substrates modulate composition, metabolism, virulence and inflammatory potential of an in vitro multi-species oral biofilm. J Oral Microbiol 2021; 13:1910462. [PMID: 33968313 PMCID: PMC8079042 DOI: 10.1080/20002297.2021.1910462] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Background: Modulation of the commensal oral microbiota constitutes a promising preventive/therapeutic approach in oral healthcare. The use of prebiotics for maintaining/restoring the health-associated homeostasis of the oral microbiota has become an important research topic. Aims: This study hypothesised that in vitro 14-species oral biofilms can be modulated by (in)direct stimulation of beneficial/commensal bacteria with new potential prebiotic substrates tested at 1 M and 1%(w/v), resulting in more host-compatible biofilms with fewer pathogens, decreased virulence and less inflammatory potential. Methods: Established biofilms were repeatedly rinsed with N-acetyl-D-glucosamine, α-D-lactose, D-(+)-trehalose or D-(+)-raffinose at 1 M or 1%(w/v). Biofilm composition, metabolic profile, virulence and inflammatory potential were eventually determined. Results: Repeated rinsing caused a shift towards a more health-associated microbiological composition, an altered metabolic profile, often downregulated virulence gene expression and decreased the inflammatory potential on oral keratinocytes. At 1 M, the substrates had pronounced effects on all biofilm aspects, whereas at 1%(w/v) they had a pronounced effect on virulence gene expression and a limited effect on inflammatory potential. Conclusion: Overall, this study identified four new potential prebiotic substrates that exhibit different modulatory effects at two different concentrations that cause in vitro multi-species oral biofilms to become more host-compatible.
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Affiliation(s)
- Tim Verspecht
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Leuven, Belgium.,Department of Biotechnology, Center for Microbial Ecology and Technology (CMET), Ghent University (UGent), Gent, Belgium
| | - Wannes Van Holm
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Leuven, Belgium.,Department of Biotechnology, Center for Microbial Ecology and Technology (CMET), Ghent University (UGent), Gent, Belgium
| | - Nico Boon
- Department of Biotechnology, Center for Microbial Ecology and Technology (CMET), Ghent University (UGent), Gent, Belgium
| | - Kristel Bernaerts
- Bio- and Chemical Systems Technology, Reactor Engineering and Safety, Department of Chemical Engineering, University of Leuven (KU Leuven), Leuven Chem & Tech, Leuven, Belgium
| | - Carlo A Daep
- Colgate-Palmolive Technology Center, Piscataway, NJ USA
| | | | - Naiera Zayed
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Leuven, Belgium.,Department of Biotechnology, Center for Microbial Ecology and Technology (CMET), Ghent University (UGent), Gent, Belgium.,Faculty of Pharmacy, Menoufia University, Egypt
| | - Marc Quirynen
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Leuven, Belgium.,Dentistry, University Hospitals Leuven, Leuven, Belgium
| | - Wim Teughels
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Leuven, Belgium.,Dentistry, University Hospitals Leuven, Leuven, Belgium
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10
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Jones IA, Joshi LT. Biocide Use in the Antimicrobial Era: A Review. Molecules 2021; 26:molecules26082276. [PMID: 33919993 PMCID: PMC8071000 DOI: 10.3390/molecules26082276] [Citation(s) in RCA: 59] [Impact Index Per Article: 19.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2020] [Revised: 04/03/2021] [Accepted: 04/06/2021] [Indexed: 12/12/2022] Open
Abstract
Biocides are widely used in healthcare and industry to control infections and microbial contamination. Ineffectual disinfection of surfaces and inappropriate use of biocides can result in the survival of microorganisms such as bacteria and viruses on inanimate surfaces, often contributing to the transmission of infectious agents. Biocidal disinfectants employ varying modes of action to kill microorganisms, ranging from oxidization to solubilizing lipids. This review considers the main biocides used within healthcare and industry environments and highlights their modes of action, efficacy and relevance to disinfection of pathogenic bacteria. This information is vital for rational use and development of biocides in an era where microorganisms are becoming resistant to chemical antimicrobial agents.
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11
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Zhang J, Kuang X, Zhou Y, Yang R, Zhou X, Peng X, Luo Y, Xu X. Antimicrobial activities of a small molecule compound II-6s against oral streptococci. J Oral Microbiol 2021; 13:1909917. [PMID: 33854741 PMCID: PMC8018465 DOI: 10.1080/20002297.2021.1909917] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Background: The side effects of present antimicrobials like chlorhexidine (CHX) and the emergence of drug resistance necessitate the development of alternative agents to control dental caries. Aim: This study developed a novel small molecule, namely II-6s, and investigated its antimicrobial activities against common oral streptococci associated with dental caries. Methods: The susceptibility of streptococci to II-6s was evaluated by the microdilution method, time-kill assay and scanning electron microscopy. The exopolysaccharides, dead/live bacteria and bacterial composition of the II-6s-treated Streptococcus mutans/Streptococcus gordonii/Streptococcus sanguinis 3-species biofilms were analyzed by confocal laser scanning microscopy, fluorescent in situ hybridization and quantitative PCR. The anti-demineralization effect and cytotoxicity of II-6s were evaluated by transverse microradiography and CCK-8 assay, respectively. Repeated exposure of S. mutans to II-6s was performed to assess if II-6s could induce drug resistance. Results: II-6s exhibited antimicrobial activity similar to CHX against S. mutans, S. gordonii and S. sanguinis and significantly inhibited exopolysaccharides production, live bacteria and the demineralizing capability of the 3-species streptococcal biofilms. Besides, II-6s showed reduced cytotoxicity relative to CHX and did not induce drug resistance in S. mutans after 15 passages. Conclusion: - II-6s may serve as a promising part of a successful caries management plan.
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Affiliation(s)
- Jin Zhang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xinyi Kuang
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Yuanzheng Zhou
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Ran Yang
- Department of Pediatric Dentistry, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Xian Peng
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Youfu Luo
- State Key Laboratory of Biotherapy, West China Hospital, Sichuan University, Chengdu, China
| | - Xin Xu
- State Key Laboratory of Oral Diseases, National Clinical Research Center for Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,Department of Cariology and Endodontics, West China Hospital of Stomatology, Sichuan University, Chengdu, China
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12
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Xi Q, Hoth-Hannig W, Deng S, Jin X, Fu B, Hannig M. The effect of polyphenol-containing solutions on in situ biofilm formation on enamel and dentin. J Dent 2020; 102:103482. [PMID: 32980427 DOI: 10.1016/j.jdent.2020.103482] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/20/2020] [Accepted: 09/22/2020] [Indexed: 01/03/2023] Open
Abstract
OBJECTIVES To investigate the effects of Chinese gallnut extracts and pure tannic acid on in situ biofilm formation on enamel and dentin samples over 24 h. METHODS Bovine enamel and dentin samples were buccally fixed on maxillary splints. Six volunteers wore the splints for 24 h, and rinsed their mouths with tap water (control), 1% tannic acid- and 1% Chinese gallnut extracts-containing solution twice a day, 3 min after the splints were placed in the mouth and before night sleep. Live/dead staining was used for fluorescence microscopic (FM) visualization and quantification of bacteria viability of biofilms formed on enamel and dentin samples. Biofilm coverage was evaluated and recorded by FM and scanning electron microscopy (SEM). In addition, biofilms were analyzed by transmission electron microscopy (TEM). The Kruskal-Wallis test was used to analyze biofilm data. RESULTS Rinsing with tannic acid- and Chinese gallnut extracts-containing solutions significantly reduced in situ biofilm coverage on enamel and dentin samples (P < 0.05). The bacterial viability of biofilms formed on enamel samples was significantly reduced compared to the control (P < 0.05). TEM analysis revealed an increase in pellicle's electron density and thickness and only few or no bacteria adherent to the pellicle in the experimental samples. CONCLUSIONS Rinsing with tannic acid- and Chinese gallnut extracts-containing solutions can effectively inhibit in situ biofilm formation, modify the ultrastructure of biofilms on enamel and dentin surfaces and significantly reduce the bacterial viability of biofilm on enamel surfaces. CLINICAL SIGNIFICANCE Tannic acid- and Chinese gallnut extracts-containing solutions might be used for dental biofilm management.
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Affiliation(s)
- Qingping Xi
- The Affiliated Stomatology Hospital, Zhejiang University School of Medicine, Yan'an Road 395, 310006, Hangzhou, China; Key Laboratory of Oral Biomedical Research of Zhejiang Province, Zhejiang University School of Stomatology, Kaixuan Road 268, 310020, Hangzhou, China; Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Building 73, Saarland University, D-66421, Homburg, Germany
| | - Wiebke Hoth-Hannig
- Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Building 73, Saarland University, D-66421, Homburg, Germany
| | - Shuli Deng
- The Affiliated Stomatology Hospital, Zhejiang University School of Medicine, Yan'an Road 395, 310006, Hangzhou, China; Key Laboratory of Oral Biomedical Research of Zhejiang Province, Zhejiang University School of Stomatology, Kaixuan Road 268, 310020, Hangzhou, China
| | - Xiaoting Jin
- The Affiliated Stomatology Hospital, Zhejiang University School of Medicine, Yan'an Road 395, 310006, Hangzhou, China; Key Laboratory of Oral Biomedical Research of Zhejiang Province, Zhejiang University School of Stomatology, Kaixuan Road 268, 310020, Hangzhou, China
| | - Baiping Fu
- The Affiliated Stomatology Hospital, Zhejiang University School of Medicine, Yan'an Road 395, 310006, Hangzhou, China; Key Laboratory of Oral Biomedical Research of Zhejiang Province, Zhejiang University School of Stomatology, Kaixuan Road 268, 310020, Hangzhou, China.
| | - Matthias Hannig
- Clinic of Operative Dentistry, Periodontology and Preventive Dentistry, Building 73, Saarland University, D-66421, Homburg, Germany.
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13
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Yaghmoor RB, Xia W, Ashley P, Allan E, Young AM. Effect of Novel Antibacterial Composites on Bacterial Biofilms. J Funct Biomater 2020; 11:jfb11030055. [PMID: 32752201 PMCID: PMC7564959 DOI: 10.3390/jfb11030055] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 07/23/2020] [Accepted: 07/27/2020] [Indexed: 02/06/2023] Open
Abstract
Continuing cariogenic bacterial growth demineralizing dentine beneath a composite filling is the most common cause of tooth restoration failure. Novel composites with antibacterial polylysine (PLS) (0, 4, 6, or 8 wt%) in its filler phase were therefore produced. Remineralising monocalcium phosphate was also included at double the PLS weight. Antibacterial studies involved set composite disc placement in 1% sucrose-supplemented broth containing Streptococcus mutans (UA159). Relative surface bacterial biofilm mass (n = 4) after 24 h was determined by crystal violet-binding. Live/dead bacteria and biofilm thickness (n = 3) were assessed using confocal laser scanning microscopy (CLSM). To understand results and model possible in vivo benefits, cumulative PLS release from discs into water (n = 3) was determined by a ninhydrin assay. Results showed biofilm mass and thickness decreased linearly by 28% and 33%, respectively, upon increasing PLS from 0% to 8%. With 4, 6, and 8 wt% PLS, respectively, biofilm dead bacterial percentages and PLS release at 24 h were 20%, 60%, and 80% and 85, 163, and 241 μg/disc. Furthermore, initial PLS release was proportional to the square root of time and levelled after 1, 2, and 3 months at 13%, 28%, and 42%. This suggested diffusion controlled release from water-exposed composite surface layers of 65, 140, and 210 μm thickness, respectively. In conclusion, increasing PLS release initially in any gaps under the restoration to kill residual bacteria or longer-term following composite/tooth interface damage might help prevent recurrent caries.
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Affiliation(s)
- Rayan B. Yaghmoor
- Department of Biomaterials and Tissue Engineering/Department of Microbial Diseases, UCL Eastman Dental Institute, London, NW3 2QG, UK;
- Department of Restorative Dentistry, Umm Al-Qura University, College of Dental Medicine, Makkah 24381, Saudi Arabia
| | - Wendy Xia
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London NW3 2QG, UK;
| | - Paul Ashley
- Unit of Paediatric Dentistry, UCL Eastman Dental Institute, London WC1E 6DE, UK;
| | - Elaine Allan
- Department of Microbial Diseases, UCL Eastman Dental Institute, London NW3 2QG, UK;
| | - Anne M. Young
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London NW3 2QG, UK;
- Correspondence:
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14
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Dima S, Lee YY, Watanabe I, Chang WJ, Pan YH, Teng NC. Antibacterial Effect of the Natural Polymer ε-Polylysine Against Oral Pathogens Associated with Periodontitis and Caries. Polymers (Basel) 2020; 12:E1218. [PMID: 32471070 PMCID: PMC7362181 DOI: 10.3390/polym12061218] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2020] [Revised: 05/13/2020] [Accepted: 05/25/2020] [Indexed: 01/29/2023] Open
Abstract
Antimicrobials are important adjuncts in the treatment of caries and periodontitis. However, increased bacterial resistance and hypersensitivity reactions to commonly used antimicrobials have led to an increasing demand for safe and natural substances. The objective of this study was to investigate the antibacterial effects of ε-polylysine against oral pathogens Streptococcus mutans and Porphyromonas gingivalis. Broth dilution assay, scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) analyses were performed to explore the antibacterial effect of ε-polylysine against S. mutans strain ATCC25175 and P. gingivalis strain ATCC332277. For the test solution, ε-polylysine was added to the bacterial suspension to prepare 0.125%, 0.25%, 0.5% and 1% ε-polylysine solutions diluted in broth medium. All four concentrations demonstrated complete inhibition of S. mutans and significantly reduced viable cell counts of P. gingivalis after 24 h. From starting inoculum of 9.15 log CFU/mL, P. gingivalis cell counts reduced to 4.01 log CFU/mL in the 0.125% ε-polylysine treatment group. SEM, CLSM, and the LIVE/DEAD bacterial assay of ε-polylysine application on P. gingivalis biofilm-dentin specimens revealed bacterial cell membrane disruption and irregular cell morphologies. The results indicated satisfactory antibacterial efficacy of ε-polylysine against P. gingivalis and S. mutans in liquid medium and as an application on biofilm-dentin specimens.
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Affiliation(s)
- Shinechimeg Dima
- School of Dentistry, College of Oral Medicine, Taipei Medical University, 250 Wu-Hsing Street, Taipei 110, Taiwan; (S.D.); (Y.-Y.L.); (W.-J.C.); (Y.-H.P.)
| | - Yin-Yin Lee
- School of Dentistry, College of Oral Medicine, Taipei Medical University, 250 Wu-Hsing Street, Taipei 110, Taiwan; (S.D.); (Y.-Y.L.); (W.-J.C.); (Y.-H.P.)
| | - Ikki Watanabe
- Gerodontology and Oral Rehabilitation, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo 113-8510, Japan;
| | - Wei-Jen Chang
- School of Dentistry, College of Oral Medicine, Taipei Medical University, 250 Wu-Hsing Street, Taipei 110, Taiwan; (S.D.); (Y.-Y.L.); (W.-J.C.); (Y.-H.P.)
- Department of Dentistry, Shuang Ho Hospital, New Taipei 23561, Taiwan
- Department of Dentistry, Taipei Medical University Hospital, 250 Wu-Hsing Street, Taipei 110, Taiwan
| | - Yu-Hua Pan
- School of Dentistry, College of Oral Medicine, Taipei Medical University, 250 Wu-Hsing Street, Taipei 110, Taiwan; (S.D.); (Y.-Y.L.); (W.-J.C.); (Y.-H.P.)
- Department of Dentistry, Chang Gung Memorial Hospital, Taipei 106, Taiwan
- Graduate Institute of Dental & Craniofacial Science, Chang Gung University, Taoyuan 333, Taiwan
- School of Dentistry, College of Medicine, China Medical University, Taichung 404, Taiwan
| | - Nai-Chia Teng
- School of Dentistry, College of Oral Medicine, Taipei Medical University, 250 Wu-Hsing Street, Taipei 110, Taiwan; (S.D.); (Y.-Y.L.); (W.-J.C.); (Y.-H.P.)
- Department of Dentistry, Taipei Medical University Hospital, 250 Wu-Hsing Street, Taipei 110, Taiwan
- Dental Department, Taipei Medical University Hospital, Taipei 110, Taiwan
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15
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Tolerance and Persister Formation in Oral Streptococci. Antibiotics (Basel) 2020; 9:antibiotics9040167. [PMID: 32276310 PMCID: PMC7235787 DOI: 10.3390/antibiotics9040167] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2020] [Revised: 04/02/2020] [Accepted: 04/06/2020] [Indexed: 01/24/2023] Open
Abstract
The aim of this study was to analyze the potential influence of long-term exposure in subinhibitory concentrations of chlorhexidine on the emergence of tolerant and/or persistent cells in oral streptococci. The two oral streptococcal isolates S. mutans ATCC25175 and S. sobrinus ATCC33402 were incubated, after long-term subinhibitory exposure to chlorhexidine, in liquid growth media containing high concentrations of chlorhexidine. A distinct subpopulation of more chlorhexidine-tolerant cells could be detected in streptococci that had been previously exposed to subinhibitory concentrations of chlorhexidine but not in the control strains. These more biocide-tolerant and persisting microbial subpopulations might also arise in vivo. Therefore, the rational and proper use of antimicrobials in dentistry, especially when used over a long period of time, is crucial.
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16
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The Contribution of Photodynamic Inactivation vs. Corsodyl Mouthwash to the Control of Streptococcus mutans Biofilms. Curr Microbiol 2020; 77:988-996. [PMID: 31997000 DOI: 10.1007/s00284-020-01901-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2019] [Accepted: 01/21/2020] [Indexed: 02/05/2023]
Abstract
This work compared the inhibition effect of the commercially available mouthwash Corsodyl, containing 0.1% chlorhexidine digluconate, and photodynamic inactivation (PDI) employing methylene blue (MB) with irradiation from a red laser on 24-h biofilms formed by Streptococcus mutans strains on hydroxyapatite surfaces. The cytotoxicity of Corsodyl and MB was evaluated by Galleria mellonella surviving assay. The viability of biofilm cells after exposure to mouthwash and PDI was determined by counting colony-forming units. The inhibitory effect of antimicrobial agents was confirmed by confocal scanning laser microscopy. MB did not exhibit a cytotoxic effect on larval survival. Non-diluted Corsodyl slightly decreased the survival of larvae. Using our PDI parameters achieved better inhibition than with non-PDI, proving a significant effect on the eradication of S. mutans biofilms and therefore could be an appropriate supplement for the eradication of dental caries.
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17
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Li YY, Li BS, Liu WW, Cai Q, Wang HY, Liu YQ, Liu YJ, Meng WY. Effects of D-arginine on <i>Porphyromonas gingivalis</i> biofilm. J Oral Sci 2020; 62:57-61. [DOI: 10.2334/josnusd.19-0075] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
Affiliation(s)
- Yu-Yang Li
- Department of Dental Implantology, School and Hospital of Stomatology, Jilin University
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling
| | - Bao-Sheng Li
- Department of Dental Implantology, School and Hospital of Stomatology, Jilin University
| | - Wei-Wei Liu
- Department of Oral and Maxillofacial Surgery, School and Hospital of Stomatology, Jilin University
| | - Qing Cai
- Department of Dental Implantology, School and Hospital of Stomatology, Jilin University
| | - Hao-Yang Wang
- Department of Dental Implantology, School and Hospital of Stomatology, Jilin University
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling
| | - Yan-Qun Liu
- Department of Dental Implantology, School and Hospital of Stomatology, Jilin University
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling
| | - Yu-Jie Liu
- Department of Dental Implantology, School and Hospital of Stomatology, Jilin University
- Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling
| | - Wei-Yan Meng
- Department of Dental Implantology, School and Hospital of Stomatology, Jilin University
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18
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Souza VGC, Lopes DF, Machado FC, Fabri RL, Apolônio ACM. The Novel Coronavirus: An Alert for Pacifiers’ Disinfection. PESQUISA BRASILEIRA EM ODONTOPEDIATRIA E CLÍNICA INTEGRADA 2020. [DOI: 10.1590/pboci.2020.070] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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19
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Verspecht T, Rodriguez Herrero E, Khodaparast L, Khodaparast L, Boon N, Bernaerts K, Quirynen M, Teughels W. Development of antiseptic adaptation and cross-adapatation in selected oral pathogens in vitro. Sci Rep 2019; 9:8326. [PMID: 31171824 PMCID: PMC6554408 DOI: 10.1038/s41598-019-44822-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 05/24/2019] [Indexed: 02/06/2023] Open
Abstract
There is evidence that pathogenic bacteria can adapt to antiseptics upon repeated exposure. More alarming is the concomitant increase in antibiotic resistance that has been described for some pathogens. Unfortunately, effects of adaptation and cross-adaptation are hardly known for oral pathogens, which are very frequently exposed to antiseptics. Therefore, this study aimed to determine the in vitro increase in minimum inhibitory concentrations (MICs) in oral pathogens after repeated exposure to chlorhexidine or cetylpyridinium chloride, to examine if (cross-)adaptation to antiseptics/antibiotics occurs, if (cross-)adaptation is reversible and what the potential underlying mechanisms are. When the pathogens were exposed to antiseptics, their MICs significantly increased. This increase was in general at least partially conserved after regrowth without antiseptics. Some of the adapted species also showed cross-adaptation, as shown by increased MICs of antibiotics and the other antiseptic. In most antiseptic-adapted bacteria, cell-surface hydrophobicity was increased and mass-spectrometry analysis revealed changes in expression of proteins involved in a wide range of functional domains. These in vitro data shows the adaptation and cross-adaptation of oral pathogens to antiseptics and antibiotics. This was related to changes in cell surface hydrophobicity and in expression of proteins involved in membrane transport, virulence, oxidative stress protection and metabolism.
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Affiliation(s)
- Tim Verspecht
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - Esteban Rodriguez Herrero
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - Ladan Khodaparast
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven (KU Leuven), Herestraat 49, 3000, Leuven, Belgium
| | - Laleh Khodaparast
- Switch Laboratory, VIB Center for Brain and Disease Research, Herestraat 49, 3000, Leuven, Belgium.,Switch Laboratory, Department of Cellular and Molecular Medicine, University of Leuven (KU Leuven), Herestraat 49, 3000, Leuven, Belgium
| | - Nico Boon
- Center for Microbial Ecology and Technology (CMET), Ghent University (UGent), Coupure links 653, 9000, Gent, Belgium
| | - Kristel Bernaerts
- Bio- and Chemical Systems Technology, Reactor Engineering and Safety, Department of Chemical Engineering, University of Leuven (KU Leuven), Leuven Chem&Tech, Celestijnenlaan 200F (bus 2424), 3001, Leuven, Belgium
| | - Marc Quirynen
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Kapucijnenvoer 33, 3000, Leuven, Belgium.,Dentistry, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium
| | - Wim Teughels
- Department of Oral Health Sciences, University of Leuven (KU Leuven), Kapucijnenvoer 33, 3000, Leuven, Belgium. .,Dentistry, University Hospitals Leuven, Kapucijnenvoer 33, 3000, Leuven, Belgium.
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20
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Cieplik F, Jakubovics NS, Buchalla W, Maisch T, Hellwig E, Al-Ahmad A. Resistance Toward Chlorhexidine in Oral Bacteria - Is There Cause for Concern? Front Microbiol 2019; 10:587. [PMID: 30967854 PMCID: PMC6439480 DOI: 10.3389/fmicb.2019.00587] [Citation(s) in RCA: 195] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Accepted: 03/07/2019] [Indexed: 12/20/2022] Open
Abstract
The threat of antibiotic resistance has attracted strong interest during the last two decades, thus stimulating stewardship programs and research on alternative antimicrobial therapies. Conversely, much less attention has been given to the directly related problem of resistance toward antiseptics and biocides. While bacterial resistances toward triclosan or quaternary ammonium compounds have been considered in this context, the bis-biguanide chlorhexidine (CHX) has been put into focus only very recently when its use was associated with emergence of stable resistance to the last-resort antibiotic colistin. The antimicrobial effect of CHX is based on damaging the bacterial cytoplasmic membrane and subsequent leakage of cytoplasmic material. Consequently, mechanisms conferring resistance toward CHX include multidrug efflux pumps and cell membrane changes. For instance, in staphylococci it has been shown that plasmid-borne qac ("quaternary ammonium compound") genes encode Qac efflux proteins that recognize cationic antiseptics as substrates. In Pseudomonas stutzeri, changes in the outer membrane protein and lipopolysaccharide profiles have been implicated in CHX resistance. However, little is known about the risk of resistance toward CHX in oral bacteria and potential mechanisms conferring this resistance or even cross-resistances toward antibiotics. Interestingly, there is also little awareness about the risk of CHX resistance in the dental community even though CHX has been widely used in dental practice as the gold-standard antiseptic for more than 40 years and is also included in a wide range of oral care consumer products. This review provides an overview of general resistance mechanisms toward CHX and the evidence for CHX resistance in oral bacteria. Furthermore, this work aims to raise awareness among the dental community about the risk of resistance toward CHX and accompanying cross-resistance to antibiotics. We propose new research directions related to the effects of CHX on bacteria in oral biofilms.
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Affiliation(s)
- Fabian Cieplik
- Department of Conservative Dentistry and Periodontology, University Medical Center Regensburg, Regensburg, Germany
| | - Nicholas S Jakubovics
- Centre for Oral Health Research, School of Dental Sciences, Newcastle University, Newcastle upon Tyne, United Kingdom
| | - Wolfgang Buchalla
- Department of Conservative Dentistry and Periodontology, University Medical Center Regensburg, Regensburg, Germany
| | - Tim Maisch
- Department of Dermatology, University Medical Center Regensburg, Regensburg, Germany
| | - Elmar Hellwig
- Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
| | - Ali Al-Ahmad
- Department of Operative Dentistry and Periodontology, Center for Dental Medicine, Faculty of Medicine, University of Freiburg, Freiburg im Breisgau, Germany
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21
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Wang S, Wang H, Ren B, Li X, Wang L, Zhou H, Weir MD, Zhou X, Masri RM, Oates TW, Cheng L, Xu HHK. Drug resistance of oral bacteria to new antibacterial dental monomer dimethylaminohexadecyl methacrylate. Sci Rep 2018; 8:5509. [PMID: 29615732 PMCID: PMC5882658 DOI: 10.1038/s41598-018-23831-3] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2017] [Accepted: 03/21/2018] [Indexed: 02/05/2023] Open
Abstract
Only two reports exist on drug-resistance of quaternary ammonium monomers against oral bacteria; both studies tested planktonic bacteria for 10 passages, and neither study tested biofilms or resins. The objectives of this study were to investigate the drug-resistance of Streptococcus mutans, Streptococcus sanguinis and Streptococcus gordonii against dimethylaminohexadecyl methacrylate (DMAHDM), and to evaluate biofilms on resins with repeated exposures for 20 passages for the first time. DMAHDM, dimethylaminododecyl methacrylate (DMADDM) and chlorhexidine (CHX) were tested with planktonic bacteria. Biofilms were grown on a resin containing 3% DMAHDM. Minimum-inhibitory concentrations were measured. To detect drug-resistance, the survived bacteria from the previous passage were used as inoculum for the next passage for repeated exposures. S. gordonii developed drug-resistance against DMADDM and CHX, but not against DMAHDM. Biofilm colony-forming units (CFU) on DMAHDM-resin was reduced by 3–4 log; there was no difference from passages 1 to 20 (p > 0.1). No drug-resistance to DMAHDM was detected for all three bacterial species. In conclusion, this study showed that DMAHDM induced no drug-resistance, and DMAHDM-resin reduced biofilm CFU by 3–4 log, with no significant change from 1 to 20 passages. DMAHDM with potent antibacterial activities and no drug-resistance is promising for dental applications.
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Affiliation(s)
- Suping Wang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Deptartment of Cariology and Endodonics West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.,Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD, 21201, USA
| | - Haohao Wang
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Deptartment of Cariology and Endodonics West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China.,Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD, 21201, USA
| | - Biao Ren
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Deptartment of Cariology and Endodonics West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China
| | - Xiaodong Li
- Department of Oral Medicine, School of Stomatology, Zhejiang University, Hangzhou, Zhejiang, China
| | - Lin Wang
- VIP Integrated Department, Stomatological Hospital of Jilin University, Changchun, China
| | - Han Zhou
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD, 21201, USA.,Maurice H. Kornberg School of Dentistry, Temple University, Philadelphia, PA, 19140, USA
| | - Michael D Weir
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD, 21201, USA
| | - Xuedong Zhou
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Deptartment of Cariology and Endodonics West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China
| | - Radi M Masri
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD, 21201, USA
| | - Thomas W Oates
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD, 21201, USA
| | - Lei Cheng
- State Key Laboratory of Oral Diseases & National Clinical Research Center for Oral Diseases & Deptartment of Cariology and Endodonics West China Hospital of Stomatology, Sichuan University, Chengdu, 610041, China. .,Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD, 21201, USA.
| | - Hockin H K Xu
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland Dental School, Baltimore, MD, 21201, USA. .,Center for Stem Cell Biology & Regenerative Medicine, University of Maryland School of Medicine, Baltimore, MD, 21201, USA. .,Department of Mechanical Engineering, University of Maryland Baltimore County, Baltimore County, MD, 21250, USA. .,Member, Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.
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22
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Qi H, Li B, Wang H, Cai Q, Quan X, Cui Y, Meng W. Effects of d-valine on periodontal or peri-implant pathogens: Porphyromonas gingivalis biofilm. J Periodontol 2018. [PMID: 29520781 DOI: 10.1002/jper.17-0405] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
BACKGROUND When presented with a surface or an interface, bacteria often grow as biofilms in which cells are held together by an extracellular matrix. Biofilm formation on implants is an initiating factor for their failure. Porphyromonas gingivalis is the primary etiologic bacteria of initiation and progression of periodontal disease. This microorganism is also the risk factor of many systemic diseases, such as cardiovascular disease, diabetes, and pulmonary infection. To date, no medication that can remove such biofilm has been accepted for clinical use. D-valine (D-val) can reportedly inhibit the formation of biofilm and/or trigger the scattering of mature biofilm. Accordingly, this study investigated the effects of d-val on single-species P. gingivalis biofilms in vitro. METHODS P. gingivalis grown in brain heart infusion culture with or without d-val was inoculated in 24- or 96-well plates. After incubation for 72 hours, biomass via crystal violet staining, extracellular polysaccharide production by biofilms, and scanning electron microscopy (SEM) were used to determine the d-val concentration that can effectively prevent P. gingivalis biofilm formation. RESULTS Experimental results showed that d-val effectively inhibited biofilm formation at concentrations ≥50 mM (mMol/L), and that d-val inhibition increased with increased concentration. Moreover, at high concentrations, the bacterial form changed from the normal baseball form into a rodlike shape. d-val also notably affected extracellular polysaccharide production by P. gingivalis. CONCLUSIONS d-val can inhibit P. gingivalis biofilm formation, and high concentrations can affect bacterial morphology.
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Affiliation(s)
- Hua Qi
- Department of Dental Implantology, School and Hospital of Stomatology, Jinlin University, Changchun, China.,Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Baosheng Li
- Department of Dental Implantology, School and Hospital of Stomatology, Jinlin University, Changchun, China
| | - Heling Wang
- Department of Dental Implantology, School and Hospital of Stomatology, Jinlin University, Changchun, China.,Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Qing Cai
- Department of Dental Implantology, School and Hospital of Stomatology, Jinlin University, Changchun, China
| | - Xu Quan
- Department of Dental Implantology, School and Hospital of Stomatology, Jinlin University, Changchun, China.,Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Yunxia Cui
- Department of Dental Implantology, School and Hospital of Stomatology, Jinlin University, Changchun, China.,Jilin Provincial Key Laboratory of Tooth Development and Bone Remodeling, Changchun, China
| | - Weiyan Meng
- Department of Dental Implantology, School and Hospital of Stomatology, Jinlin University, Changchun, China
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Tartaglia GM, Kumar S, Fornari CD, Corti E, Connelly ST. Mouthwashes in the 21 st century: a narrative review about active molecules and effectiveness on the periodontal outcomes. Expert Opin Drug Deliv 2016; 14:973-982. [PMID: 27835926 DOI: 10.1080/17425247.2017.1260118] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
INTRODUCTION Poor oral hygiene is a major risk factor for oral diseases. Regular home-based care is essential to maintain good oral hygiene. In particular, mouthrinses can support conventional tooth brushing in reducing accumulation of oral plaque. Areas covered: The most common molecules contained in mouthrinses (chlorhexidine, essential oils, cetyl pyridinium chloride, triclosan, octeneidine, delmopinol, polyvinylpyrrolidone, hyaluronic acid, natural compounds) are discussed, together with relevant clinical and in vitro studies, focusing on their effects on periodontal health. Currently, chlorhexidine is the most efficacious compound, with both antiplaque and antibacterial activities. Similar results are reported for essential oils and cetyl pyridinium chloride, although with a somewhat reduced efficacy. Considering the adverse effects of chlorhexidine and its time-related characteristics, this molecule may best be indicated for acute/short-term use, while essential oils and cetyl pyridinium chloride may be appropriate for long-term, maintenance treatment. Expert opinion: The literature has not clearly demonstrated which compound is the best for mouthrinses that combine good efficacy and acceptable side effects. Research should focus on substances with progressive antibacterial activity, prompting a gradual change in the composition of oral biofilm and mouthrinses that combine two or more molecules acting synergistically in the mouth.
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Affiliation(s)
- Gianluca M Tartaglia
- a Department of Biomedical Sciences for Health, Functional Anatomy Research Center (FARC) , Università degli Studi di Milano , Milano , Italy.,b SST Dental Clinic , Segrate , Italy
| | - Santhosh Kumar
- c Population and Social Health Research Programme, Menzies Health Institute Queensland and School of Dentistry and Oral Health, Griffith University , Gold Coast , Australia
| | | | - Eleonora Corti
- d Department of Regulatory Affairs , Biokosmes srl , Bosisio Parini , Italy
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Panpisut P, Liaqat S, Zacharaki E, Xia W, Petridis H, Young AM. Dental Composites with Calcium / Strontium Phosphates and Polylysine. PLoS One 2016; 11:e0164653. [PMID: 27727330 PMCID: PMC5058497 DOI: 10.1371/journal.pone.0164653] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2016] [Accepted: 09/28/2016] [Indexed: 12/25/2022] Open
Abstract
Purpose This study developed light cured dental composites with added monocalcium phosphate monohydrate (MCPM), tristrontium phosphate (TSrP) and antimicrobial polylysine (PLS). The aim was to produce composites that have enhanced water sorption induced expansion, can promote apatite precipitation and release polylysine. Materials and Methods Experimental composite formulations consisted of light activated dimethacrylate monomers combined with 80 wt% powder. The powder phase contained a dental glass with and without PLS (2.5 wt%) and/or reactive phosphate fillers (15 wt% TSrP and 10 wt% MCPM). The commercial composite, Z250, was used as a control. Monomer conversion and calculated polymerization shrinkage were assessed using FTIR. Subsequent mass or volume changes in water versus simulated body fluid (SBF) were quantified using gravimetric studies. These were used, along with Raman and SEM, to assess apatite precipitation on the composite surface. PLS release was determined using UV spectroscopy. Furthermore, biaxial flexural strengths after 24 hours of SBF immersion were obtained. Results Monomer conversion of the composites decreased upon the addition of phosphate fillers (from 76 to 64%) but was always higher than that of Z250 (54%). Phosphate addition increased water sorption induced expansion from 2 to 4% helping to balance the calculated polymerization shrinkage of ~ 3.4%. Phosphate addition promoted apatite precipitation from SBF. Polylysine increased the apatite layer thickness from ~ 10 to 20 μm after 4 weeks. The novel composites showed a burst release of PLS (3.7%) followed by diffusion-controlled release irrespective of phosphate addition. PLS and phosphates decreased strength from 154 MPa on average by 17% and 18%, respectively. All formulations, however, had greater strength than the ISO 4049 requirement of > 80 MPa. Conclusion The addition of MCPM with TSrP promoted hygroscopic expansion, and apatite formation. These properties are expected to help compensate polymerization shrinkage and help remineralize demineralized dentin. Polylysine can be released from the composites at early time. This may kill residual bacteria.
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Affiliation(s)
- Piyaphong Panpisut
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
| | - Saad Liaqat
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS, Lahore, Pakistan
| | - Eleni Zacharaki
- Department of Restorative Dentistry, Unit of Prosthodontics, UCL Eastman Dental Institute, London, United Kingdom
| | - Wendy Xia
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
| | - Haralampos Petridis
- Department of Restorative Dentistry, Unit of Prosthodontics, UCL Eastman Dental Institute, London, United Kingdom
| | - Anne Margaret Young
- Department of Biomaterials and Tissue Engineering, UCL Eastman Dental Institute, London, United Kingdom
- * E-mail:
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Łysakowska ME, Sienkiewicz M, Banaszek K, Sokołowski J. The Sensitivity of Endodontic Enterococcus spp. Strains to Geranium Essential Oil. Molecules 2015; 20:22881-9. [PMID: 26703546 PMCID: PMC6332067 DOI: 10.3390/molecules201219888] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2015] [Revised: 12/07/2015] [Accepted: 12/14/2015] [Indexed: 02/07/2023] Open
Abstract
Enterococci are able to survive endodontic procedures and contribute to the failure of endodontic therapy. Thus, it is essential to identify novel ways of eradicating them from infected root canals. One such approach may be the use of antimicrobials such as plant essential oils. Enterococcal strains were isolated from endodontically treated teeth by standard microbiological methods. Susceptibility to antibiotics was evaluated by the disc-diffusion method. The minimal inhibitory concentration (MIC) of geranium essential oil was investigated by microdilution in 96-well microplates in Mueller Hinton Broth II. Biofilm eradication concentrations were checked in dentin tests. Geranium essential oil inhibited enterococcal strains at concentrations ranging from 1.8-4.5 mg/mL. No correlation was shown between resistance to antibiotics and the MICs of the test antimicrobials. The MICs of the test oil were lower than those found to show cytotoxic effects on the HMEC-1 cell line. Geranium essential oil eradicated enterococcal biofilm at concentrations of 150 mg/mL. Geranium essential oil inhibits the growth of endodontic enterococcal species at lower concentrations than those required to reach IC50 against the HMEC-1 cell line, and is effective against bacteria protected in biofilm at higher concentrations. In addition, bacteria do not develop resistance to essential oils. Hence, geranium essential oil represents a possible alternative to other antimicrobials during endodontic procedures.
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Affiliation(s)
- Monika E Łysakowska
- Department of Microbiology and Medical Laboratory Immunology, Medical University of Lodz, 92-231 Lodz, Pomorska 251, Poland.
| | - Monika Sienkiewicz
- Department of Environmental Biology, Medical University of Lodz, 90-752 Lodz, Żeligowskiego 7/9, Poland.
| | - Katarzyna Banaszek
- Department of General Dentistry, Medical University of Lodz, 92-231 Lodz, Pomorska 251, Poland.
| | - Jerzy Sokołowski
- Department of General Dentistry, Medical University of Lodz, 92-231 Lodz, Pomorska 251, Poland.
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Nelson-Filho P, Louvain MC, Macari S, Lucisano MP, Silva RABD, Queiroz AMD, Gaton-Hernández P, Silva LABD. Microbial contamination and disinfection methods of pacifiers. J Appl Oral Sci 2015; 23:523-8. [PMID: 26537723 PMCID: PMC4621945 DOI: 10.1590/1678-775720150244] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2015] [Accepted: 07/28/2015] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES To evaluate the microbial contamination of pacifiers by Mutans Streptococci(MS) and the efficacy of different methods for their disinfection. METHODS Twenty-eight children were assigned to a 4-stage changeover system with a 1-week interval. In each stage, children received a new pacifier and the parents were instructed to maintain their normal habits for 1 week. After this time, the pacifiers were subjected to the following 4 disinfection methods: spraying with 0.12% chlorhexidine solution, Brushtox or sterile tap water, and immersion in boiling tap water for 15 minutes. Microbiological culture for MS and Scanning Electron Microscopy (SEM) were performed. The results were analyzed statistically by Friedman's non-parametric test (a=0.05). RESULTS The 0.12% chlorhexidine spray was statistically similar to the boiling water (p>0.05) and more effective than the Brushtox spray and control (p<0.05). The analysis of SEM showed the formation of a cariogenic biofilm in all groups with positive culture. CONCLUSIONS Pacifiers become contaminated by MS after their use by children and should be disinfected routinely. Spraying with a 0.12% chlorhexidine solution and immersion in boiling water promoted better disinfection of the pacifiers compared with a commercial antiseptic toothbrush cleanser (Brushtox).
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Affiliation(s)
- Paulo Nelson-Filho
- Departamento de Odontopediatria, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | | | - Soraia Macari
- Departamento de Clínica, Patologia e Cirurgia Odontológicas, Faculdade de Odontologia, Universidade Federal de Minas Gerais, Belo Horizonte, MG, Brazil
| | - Marília Pacífico Lucisano
- Departamento de Odontopediatria, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Raquel Assed Bezerra da Silva
- Departamento de Odontopediatria, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Alexandra Mussolino de Queiroz
- Departamento de Odontopediatria, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
| | - Patrícia Gaton-Hernández
- Departament d'Odontostomatologia, Facultat d'Odontologia, Universitat de Barcelona, Barcelona, Spain
| | - Léa Assed Bezerra da Silva
- Departamento de Odontopediatria, Faculdade de Odontologia de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, SP, Brazil
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Garner S, Barbour ME. Nanoparticles for controlled delivery and sustained release of chlorhexidine in the oral environment. Oral Dis 2015; 21:641-4. [DOI: 10.1111/odi.12328] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2015] [Revised: 02/04/2015] [Accepted: 02/09/2015] [Indexed: 11/29/2022]
Affiliation(s)
- S Garner
- Oral Nanoscience; School of Oral and Dental Sciences; University of Bristol; Bristol UK
| | - ME Barbour
- Oral Nanoscience; School of Oral and Dental Sciences; University of Bristol; Bristol UK
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