Publications by authors named "Rukke H"

Objectives: Assess the antibacterial, physical and chemical properties of AH Plus, BioRoot RCS and Pulp Canal Sealer (PCS) in contact with 2% chlorhexidine digluconate (CHX) used as final irrigant prior to root canal obturation.

Methods: The antimicrobial properties were investigated by direct contact tests for planktonic and biofilm growth of E. faecalis, S.

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Background: Leakage of unpolymerized methacrylate monomers after placement of methacrylate-containing polymeric dental materials leads to human exposure. Based on studies using murine macrophages and LPS from Escherichia coli (E. coli), dental monomers like 2-hydroxyethyl methacrylate (HEMA) are known to inhibit lipopolysaccharide (LPS) induced cytokine release.

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The lifespan of a resin-based restoration is limited, with the main reason for failure being secondary caries. Biofilm formation at the tooth-material interface is a necessary etiological agent for caries development. Dental materials with antimicrobial properties may reduce formation of biofilm and thus increase the longevity of restorations.

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Introduction: The aim of this study was to investigate the antibacterial activity of 4 endodontic sealers against bacteria planktonic grown or in biofilms commonly detected from persistent and secondary endodontic infections.

Methods: The antibacterial activity of the sealers AH Plus, TotalFill BC sealer, RoekoSeal, and Guttaflow 2 was investigated for planktonic grown and 24-hour-old biofilms of Enterococcus faecalis, Staphylococcus epidermidis, Staphylococcus aureus, and Streptococcus mutans.

Results: AH Plus had high antibacterial activity toward all species investigated, both planktonic and in biofilms.

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Natural deep eutectic solvents (NADES) are a third class of liquids, separate from water and lipids. Some NADES, especially those containing organic acids, have been suggested to possess antimicrobial properties. Such properties may be advantageous when NADES are used as solvents in e.

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Objectives: This study aimed to investigate dentists' exposure to curing light and to obtain information about the dentists' knowledge on practical use and technical features of their curing lights as well as their safety awareness.

Methods: A pre-coded questionnaire was sent electronically to all dentists (n=1313) in the Public Dental Service (PDS) in Norway in 2015.

Results: The Response rate was 55.

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In , an oral colonizer associated with dental caries, development of competence for natural genetic transformation is triggered by either of two types of peptide pheromones, competence-stimulating peptides (CSPs) (18 amino acids [aa]) or SigX-inducing peptides (XIPs) (7 aa). Competence induced by CSP is a late response to the pheromone that requires the response regulator ComE and the XIP-encoding gene . XIP binds to ComR to allow expression of the alternative sigma factor SigX and the effector genes it controls.

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Aim. The aim of this study was to investigate the antibacterial and antibiofilm properties of low viscosity chitosan on S. epidermidis growth and biofilm formation.

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Objectives: This study aimed to investigate dentists' treatment choices concerning "repair or replacement" of defective restorations.

Methods: A pre-coded questionnaire was sent electronically to all dentists (n=1313) in the Public Dental Service (PDS) in Norway. Part one: The dentists were asked about age and gender, whether they performed direct restorative therapy/amount of time spent on fillings made per day due to: Primary caries, Repair of restorations or Replacement of restoration/what kind of bonding agents used and pre-treatment of the residual restoration.

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Natural deep eutectic solvents (NADES) are a newly discovered group of eutectics which has shown promise as a solvent in antimicrobial photodynamic therapy (aPDT). The purpose of this study was to investigate preparations of an anionic porphyrin, meso-tetra-(4-carboxyphenyl)-porphine (TCPP), solubilised in NADES, with regard to their physicochemical and antibacterial properties. The NADES CS (pH∼0), ChX (pH∼4) and MFG (pH∼1) solubilised TCPP with absorption maximum ∼443nm and emission maximum ∼678nm, indicating formation of the TCPP dication.

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Streptococcus mitis is a colonizer of the oral cavity and the nasopharynx, and is closely related to Streptococcus pneumoniae. Both species occur in encapsulated and unencapsulated forms, but in S. mitis the role of the capsule in host interactions is mostly unknown.

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The polysaccharide capsule surrounding Streptococcus pneumoniae is essential for virulence. Recently, Streptococcus mitis, a human commensal and a close relative of S. pneumoniae, was also shown to have a capsule.

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The competence-stimulating peptide (CSP) and the sigX-inducing peptide (XIP) are known to induce Streptococcus mutans competence for genetic transformation. For both pheromones, direct identification of the native peptides has not been accomplished. The fact that extracellular XIP activity was recently observed in a chemically defined medium devoid of peptides, as mentioned in an accompanying paper (K.

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The polysaccharide capsule of Streptococcus pneumoniae is a hallmark for virulence in humans. In its close relative Streptococcus mitis, a common human commensal, analysis of the sequenced genomes of six strains revealed the presence of a putative capsule locus in four of them. We constructed an isogenic S.

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