Cultivated and not-yet-cultivated bacteria in oral biofilms

AbstractCinnamon essential oil (CEO) has antibacterial properties, but its ability to suppress the formation of multi-species oral biofilms has not been fully elucidated. This study evaluated the antibacterial and antibiofilm activities of cinnamon essential oil nanoemulsion (CEON) against oral biofilms formed using a microcosm biofilm model. The biofilms were formed on bovine enamel specimens over a 7-day period, during which all specimens were treated with one of three solutions: 5% CEON (n = 35), 0.5% cocamidopropyl betaine (n = 35), or 0.12% chlorhexidine gluconate (CHX; n = 35). Antibacterial and antibiofilm activities were determined by the red/green ratios (R/G values) of 7-day-old mature biofilms photographed with quantitative light-induced fluorescence-digital, the number of aciduric bacterial colony-forming units (CFUs) within each biofilm, and the absorbance of bacterial suspensions. One-way and repeated-measures analysis of variance were performed to compare differences among the three solutions. R/G values were lowest in the 0.12% CHX group, but not significantly differ from the 5% CEON group. The number of CFUs and absorbance were lowest in the 5% CEON group. This study showed that nanoemulsified CEO inhibited the maturation of multi-species oral biofilms and the growth of oral microorganisms in biofilms, including aciduric bacteria that cause dental caries.

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Acid tolerance in early colonizers of oral biofilms

BMC Microbiology ◽

10.1186/s12866-021-02089-2 ◽

2021 ◽

Vol 21 (1) ◽

Author(s):

Gabriella Boisen ◽

Julia R. Davies ◽

Jessica Neilands

Keyword(s):

Acid Tolerance ◽

Low Ph ◽

Salivary Proteins ◽

Confocal Scanning Laser Microscopy ◽

Planktonic Cells ◽

Tolerance Development ◽

Salivary Pellicle ◽

Oral Biofilms ◽

Acid Tolerant

Abstract Background In caries, low pH drives selection and enrichment of acidogenic and aciduric bacteria in oral biofilms, and development of acid tolerance in early colonizers is thought to play a key role in this shift. Since previous studies have focussed on planktonic cells, the effect of biofilm growth as well as the role of a salivary pellicle on this process is largely unknown. We explored acid tolerance and acid tolerance response (ATR) induction in biofilm cells of both clinical and laboratory strains of three oral streptococcal species (Streptococcus gordonii, Streptococcus oralis and Streptococcus mutans) as well as two oral species of Actinomyces (A. naeslundii and A. odontolyticus) and examined the role of salivary proteins in acid tolerance development. Methods Biofilms were formed on surfaces in Ibidi® mini flow cells with or without a coating of salivary proteins and acid tolerance assessed by exposing them to a challenge known to kill non-acid tolerant cells (pH 3.5 for 30 min) followed by staining with LIVE/DEAD BacLight and confocal scanning laser microscopy. The ability to induce an ATR was assessed by exposing the biofilms to an adaptation pH (pH 5.5) for 2 hours prior to the low pH challenge. Results Biofilm formation significantly increased acid tolerance in all the clinical streptococcal strains (P < 0.05) whereas the laboratory strains varied in their response. In biofilms, S. oralis was much more acid tolerant than S. gordonii or S. mutans. A. naeslundii showed a significant increase in acid tolerance in biofilms compared to planktonic cells (P < 0.001) which was not seen for A. odontolyticus. All strains except S. oralis induced an ATR after pre-exposure to pH 5.5 (P < 0.05). The presence of a salivary pellicle enhanced both acid tolerance development and ATR induction in S. gordonii biofilms (P < 0.05) but did not affect the other bacteria to the same extent. Conclusions These findings suggest that factors such as surface contact, the presence of a salivary pellicle and sensing of environmental pH can contribute to the development of high levels of acid tolerance amongst early colonizers in oral biofilms which may be important in the initiation of caries.

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The Role of Exopolysaccharides in Oral Biofilms

Journal of Dental Research ◽

10.1177/0022034519845001 ◽

2019 ◽

Vol 98 (7) ◽

pp. 739-745 ◽

Cited By ~ 7

Author(s):

C. Cugini ◽

M. Shanmugam ◽

N. Landge ◽

N. Ramasubbu

Keyword(s):

Biofilm Formation ◽

Bacterial Colonization ◽

Super Resolution ◽

Extracellular Proteins ◽

Extracellular Polysaccharides ◽

Oral Biofilms ◽

The Matrix ◽

Oral Microbes ◽

Biofilm Development

The oral cavity contains a rich consortium of exopolysaccharide-producing microbes. These extracellular polysaccharides comprise a major component of the oral biofilm. Together with extracellular proteins, DNA, and lipids, they form the biofilm matrix, which contributes to bacterial colonization, biofilm formation and maintenance, and pathogenesis. While a number of oral microbes have been studied in detail with regard to biofilm formation and pathogenesis, the exopolysaccharides have been well characterized for only select organisms, namely Streptococcus mutans and Aggregatibacter actinomycetemcomitans. Studies on the exopolysaccharides of other oral organisms, however, are in their infancy. In this review, we present the current research on exopolysaccharides of oral microbes regarding their biosynthesis, regulation, contributions to biofilm formation and stability of the matrix, and immune evasion. In addition, insight into the role of exopolysaccharides in biofilms is highlighted through the evaluation of emerging techniques such as pH probing of biofilm colonies, solid-state nuclear magnetic resonance for macromolecular interactions within biofilms, and super-resolution microscopy analysis of biofilm development. Finally, exopolysaccharide as a potential nutrient source for species within a biofilm is discussed.

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Novel Protein-Repellent and Antibacterial Resins and Cements to Inhibit Lesions and Protect Teeth

International Journal of Polymer Science ◽

10.1155/2019/5602904 ◽

2019 ◽

Vol 2019 ◽

pp. 1-11 ◽

Cited By ~ 5

Author(s):

Li Cao ◽

Junling Wu ◽

Qiang Zhang ◽

Bashayer Baras ◽

Ghalia Bhadila ◽

...

Keyword(s):

Orthodontic Treatment ◽

The Novel ◽

Dental Resin ◽

Biofilm Growth ◽

New Class ◽

Dental Resins ◽

Wide Range ◽

Oral Biofilms ◽

One Year

Orthodontic treatment is increasingly popular as people worldwide seek esthetics and better quality of life. In orthodontic treatment, complex appliances and retainers are placed in the patients’ mouths for at least one year, which often lead to biofilm plaque accumulation. This in turn increases the caries-inducing bacteria, decreases the pH of the retained plaque on an enamel surface, and causes white spot lesions (WSLs) in enamel. This article reviews the cutting-edge research on a new class of bioactive and therapeutic dental resins, cements, and adhesives that can inhibit biofilms and protect tooth structures. The novel approaches include the use of protein-repellent and anticaries polymeric dental cements containing 2-methacryloyloxyethyl phosphorylcholine (MPC) and dimethylaminododecyl methacrylate (DMAHDM); multifunctional resins that can inhibit enamel demineralization; protein-repellent and self-etching adhesives to greatly reduce oral biofilm growth; and novel polymethyl methacrylate resins to suppress oral biofilms and acid production. These new materials could reduce biofilm attachment, raise local biofilm pH, and facilitate the remineralization to protect the teeth. This novel class of dental resin with dual benefits of antibacterial and protein-repellent capabilities has the potential for a wide range of dental and biomedical applications to inhibit bacterial infection and protect the tissues.

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Synergistic effect of xylitol and ursolic acid combination on oral biofilms

Restorative Dentistry & Endodontics ◽

10.5395/rde.2014.39.4.288 ◽

2014 ◽

Vol 39 (4) ◽

pp. 288 ◽

Cited By ~ 13

Author(s):

Yunyun Zou ◽

Yoon Lee ◽

Jinyoung Huh ◽

Jeong-Won Park

Keyword(s):

Synergistic Effect ◽

Ursolic Acid ◽

Oral Biofilms

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Interfacial degradation of adhesive composite restorations mediated by oral biofilms and mechanical challenge in an extracted tooth model of secondary caries

Journal of Dentistry ◽

10.1016/j.jdent.2017.08.009 ◽

2017 ◽

Vol 66 ◽

pp. 62-70 ◽

Cited By ~ 3

Author(s):

Carola A. Carrera ◽

Yuping Li ◽

Ruoquiong Chen ◽

Conrado Aparicio ◽

Alex Fok ◽

...

Keyword(s):

Secondary Caries ◽

Composite Restorations ◽

Oral Biofilms

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Saliva-Derived Commensal and Pathogenic Biofilms in a Human Gingiva Model

Journal of Dental Research ◽

10.1177/0022034517729998 ◽

2017 ◽

Vol 97 (2) ◽

pp. 201-208 ◽

Cited By ~ 13

Author(s):

J.K. Buskermolen ◽

M.M. Janus ◽

S. Roffel ◽

B.P. Krom ◽

S. Gibbs

Keyword(s):

Oral Mucosa ◽

Bacterial Species ◽

Human Saliva ◽

In Vitro Models ◽

Antimicrobial Protein ◽

Operational Taxonomic Units ◽

Oral Biofilms ◽

Human Gingiva ◽

Pathogenic Biofilms

In vitro models that closely mimic human host-microbiome interactions can be a powerful screening tool for antimicrobials and will hold great potential for drug validation and discovery. The aim of this study was to develop an organotypic oral mucosa model that could be exposed to in vitro cultured commensal and pathogenic biofilms in a standardized and scalable manner. The oral mucosa model consisted of a tissue-engineered human gingiva equivalent containing a multilayered differentiated gingiva epithelium (keratinocytes) grown on a collagen hydrogel, containing gingiva fibroblasts, which represented the lamina propria. Keratinocyte and fibroblast telomerase reverse transcriptase–immortalized cell lines were used to overcome the limitations of isolating cells from small biopsies when scalable culture experiments were required. The oral biofilms were grown under defined conditions from human saliva to represent 3 distinct phenotypes: commensal, gingivitis, and cariogenic. The in vitro grown biofilms contained physiologic numbers of bacterial species, averaging >70 operational taxonomic units, including 20 differentiating operational taxonomic units. When the biofilms were applied topically to the gingiva equivalents for 24 h, the gingiva epithelium increased its expression of elafin, a protease inhibitor and antimicrobial protein. This increased elafin expression was observed as a response to all 3 biofilm types, commensal as well as pathogenic (gingivitis and cariogenic). Biofilm exposure also increased secretion of the antimicrobial cytokine CCL20 and inflammatory cytokines IL-6, CXCL8, and CCL2 from gingiva equivalents. This inflammatory response was far greater after commensal biofilm exposure than after pathogenic biofilm exposure. These results show that pathogenic oral biofilms have early immune evasion properties as compared with commensal oral biofilms. The novel host-microbiome model provides an ideal tool for future investigations of gingiva responses to commensal and pathogenic biofilms and for testing novel therapeutics.

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MODERN SUBMISSION OF FORMATION, COMPOSITION AND ROLE OF ORAL (DENTAL) BIOFILM IN DEVELOPMENT OF PERIODONTAL DISEASES

Wiadomości Lekarskie ◽

10.36740/wlek202008132 ◽

2020 ◽

Vol 73 (8) ◽

pp. 1761-1764

Author(s):

Maria O. Stetsyk ◽

Andriy O. Stetsyk ◽

Natalia I. Zhero ◽

Eugene Y. Kostenko ◽

Svetlana B. Kostenko ◽

...

Keyword(s):

Detailed Analysis ◽

Inflammatory Diseases ◽

Periodontal Diseases ◽

Oral Biofilm ◽

Dental Biofilm ◽

Periodontal Tissues ◽

Current Trends ◽

Oral Biofilms ◽

Depth Study

The aim: To investigate current trends in the study of oral biofilm and its control. Materials and methods: A research of 32 literature sources has been made and it has been taken into account that some terminological differences in determining objects of study. Conclusions: Detailed analysis of modern domestic and foreign literature argues the necessity of further in-depth study of oral biofilms. Understanding the ethiological factors and mechanisms of the pathogenesis periodontal tissues inflammatory diseases gives the opportunity to treat targetly by destroying complicated sections of the vital activities and oral biofilm microorganisms relationships.

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