Hyperspectral fluorescence characterisation of bacteria. -

Some strains of bacteria are known to fluoresce when exposed to UV-light, and are therefore detectable using spectroscopy techniques. If we could differentiate bacteria only based on an image, we open for a range of new methods within the field of microbial diagnostics. This is the underlying idea for our project. As we acquire hyperspectral images of a series of different bacteria, we aim to map their spectral “fingerprint” in a spatial manner. These first investigations make up a feasibility study which is continued this spring to allow for a more complete study.

Comprehensive Transcriptome Profiles of Streptococcus mutans UA159 Map Core Streptococcal Competence Genes -

In Streptococcus mutans, 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

Effect of Components in Resin-Based Dental Restoratives on Protein-S-Glutathionylation -

Protein S-glutathionylation (PSSG) is the reversible formation of mixed disulfides between glutathione and protein cysteinyl residues.

Exposure to Dental Monomer Hydroxyethyl Methacrylate (HEMA) Induces Increased Transcription of Genes Involved in Oxidative Stress Responses -

Polymer-based restorative materials are widely used in dentistry. Cured materials contain unpolymerized methacrylate monomers which leak into the oral environment.

Effekter i munnhulen ved bruk av snus -

Snus is a smokeless, ground tobacco product, which is most commonly placed in the mouth between the gum and lip. Like other tobacco products, snus contains the biologically active and addictive substance, nicotine.

Occlusal Caries Management: Preferences among Dentists in Norway -

The aim was to measure variations in the threshold for operative treatment of occlusal caries in permanent teeth and the use of dental materials, compared with results from a similar study conducted in Norway in 1995.

The safety of the use of bisphenol A in medical devices -

The European Commission’s independent Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) recently published its risk assessment of exposure to BPA via medical devices that are manufactured with materials that potentially leach BPA leading to oral (via dental material), subcutaneous and intravenous (e.g. during hemodialysis) routes of exposure.

Posterior composites and new caries on adjacent surfaces – any association? Longitudinal study with a split-mouth design -

The aim of this longitudinal study was to compare caries incidence in sound approximal surfaces adjacent to newly placed composite restorations with the caries incidence in corresponding surfaces in contralateral teeth without any restorations in contact; and to assess risk factors for dentine caries development on adjacent and control surfaces.

The safety of dental amalgam and alternative dental restoration materials for patients and users -

The European Commission asked its independent Scientific Committee on Emerging and Newly Identified Health Risks (SCENIHR) to provide a risk assessment on dental amalgam and alternatives such as resin-based composites, glass ionomer cements, ceramics and gold alloys to update the SCENIHR’s 2008 Opinion in light of new developments and data.

Load at fracture of monolithic and bilayered zirconia crowns with and without a cervical zirconia collar -

The effect of anatomic contour design in all or parts of zirconia crowns is uncertain regarding clinical reliability and survival rates.

Toxicity of plast materials -

The term «resin-based dental materials» refers to dental materials containing polymers. Usually, these polymers are formed by in situ polymerization of methacrylate monomers.

Interactions of liposomes with dental restorative materials -

The in vitro adsorption and retention of liposomes onto four common types of dental restorative materials (conventional and silorane-based resin composites as well as conventional and resin-modified glass ionomer cements (GIC)) have been investigated due to their potential use in the oral cavity.

Characterization and antimicrobial phototoxicity of curcumin dissolved in natural deep eutectic solvents -

The purpose of the current study was to evaluate the potential of NADES as a solvent for the hydrophobic photosensitizer curcumin for use in antimicrobial photodynamic therapy (aPDT).

NIOM representation at EDM 2015 -

The 23rd European Dental Materials Conference was held in Nürnberg, Germany, on August 27 and 28, 2015.

Risk factors for caries development on tooth surfaces adjacent to newly placed Class II composites – a pragmatic, practice based study -

To assess risk factors for caries development on approximal surfaces in contact with newly placed Class II composite restorations.

Cyclodextrins influence on lumichrome solubilization and phototoxic efficacy against bacteria. -

Lumichrome (Lc) is a photodegradation product of riboflavin. It is more photostable and a more efficient photogenerator of singlet oxygen than riboflavin. Lc absorbs mainly in the UVA range. Cyclodextrins (CDs) are reported to be very efficient solubility enhancers of Lc in aqueous solutions. A 1:1 inclusion complex has been predicted between Lc and α and βCDs (Terekhova, Kumeev et al. 2011). The aim of the present study was to evaluate the influence of CDs on solubility and on the bacterial phototoxicity of Lc in vitro.

Evaluation of material suitability for nanoparticle-based coatings and further antimicrobial treatment -

Dental materials are easily colonized by bacteria, and microbial attack is the main cause of dental implant failure and periodontitis. The aim of this project was to formulate nanoparticle-based (NPsol) coatings that reduce bacterial adherence on materials used in dentistry. Pre-treatment of the surfaces with such coatings could create a time window that allows for killing of the surrounding bacteria prior to or shortly after adhesion. One option is to apply antimicrobial photodynamic therapy (aPDT).

Silanising agents promote resin-composite repair -

The aim of this study was to investigate the effect of silane in the repair of old and new resin-composite restorations.

In vitro element release and biological aspects of base-metal alloys for metal-ceramic applications -

Abstract Objective The aims of this study were to investigate the release of element from, and the biological response in vitro to, cobalt–chromium alloys and other base–metal alloys used for the fabrication of metal-ceramic restorations. Material and methods: Eighteen different alloys were investigated. Nine cobalt–chromium alloys, three nickel–chromium alloys, two cobalt–chromium–iron alloys, one palladium–silver alloy, […]

Scientific Opinion on the safety of dental amalgam and alternative dental restoration materials for patients and users -

In the light of new developments and studies on dental amalgam a request was submitted by the Commission to update the SCENIHR opinion produced in 2008 on the safety and performance of both dental amalgam and possible alternatives, such as resin-based composites, glass ionomer cements, ceramics and gold alloys.

Evaluation of eye protection in occupational use of non-coherent optical sources -

Blue light and ultraviolet radiation can cause acute eye hazards. Further, increasing evidence suggests that blue light contributes to chronic diseases, such as cataracts and age-related macular degeneration. The use of optical radiation protective devices, such as goggles, is a simple means to avoid eye damage when working with high irradiance sources.

Influence of formulation on photoinactivation of bacteria by lumichrome. -

The aim of this study was to investigate the in vitro aPDT effect of various lumichrome pharmaceutical formulations

The effect of margin curvature on load at fracture of ceramic crowns -

The aim of this study was to use a clinically relevant test method to evaluate the effect of the curvature of the cervical crown margins on load at fracture

Cell toxicity of 2-hydroxyethyl methacrylate (HEMA): the role of oxidative stress -

In this study, the viability of human lung epithelial cells, BEAS-2B, was investigated after exposure to this monomer. Exposure to HEMA reduced the viability of the BEAS-2B cells as a result of increased apoptosis, interruption of the cell cycle, and decreased cell proliferation.

Relative Efficiency Of Ultraviolet Radiation A And B Combined With A Chemical Stressor On Zebrafish Embryos -

Organisms living in aquatic ecosystems may experience high doses of natural UV radiation. UV radiation penetrates the water column down to several meters. The penetration depth differs depending on the contents of particles, dissolved matter or pollutants. The aim of this study was to establish the dose-response relationship of phenotypic changes caused by UV.

Cements for gold inlays -

Gold inlays have for a long time been known as high quality restorations. Since dental amalgam is no longer applicable as filling material in Norway, the need for gold inlays has expanded, especially in patients having high chewing force and tooth abrasions who need replacement of their old amalgam fillings.

Improved antibacterial phototoxicity of a neutral porphyrin in natural deep eutectic solvents -

Neutral porphyrins for antibacterial photodynamic therapy (aPDT) have received little attention due to their tendency to aggregate in aqueous media and reports of low phototoxic effect. These compounds may be less toxic to cells than positively and negatively charged photosensitisers.

Patient satisfaction and complications of over-the-counter bleaching products -

To compare two home-based over-the-counter (OTC) bleaching tray products with similar hydrogen peroxide (HP) concentrations with respect to tooth lightening efficacy and potential to induce negative side effects in tobacco- and non-tobacco users as well as degree of satisfaction with product handling. The HP concentrations were near the regulation limit for bleaching products of 6% set by the European Union in 2011.

Safety of the use of bisphenol A in medical devices -

Bisphenol A (BPA) is a key building block of polycarbonate plastic and a precursor for the manufacturing of monomers of epoxy resins. The BPA exposure of the general population is via food as a result of the use of BPA in food packaging and via skin as a result of contact with thermal paper. The vast majority of the population (91–99%) has detectable levels of BPA-conjugates in their urine. BPA is also present in medical devices including implants, catheters, tubing, and some dental materials.

Placebo/nocebo -

Placebo was originally defined as an inactive medication giving a positive effect, whereas nocebo gives the opposite result. Both situations are based on expectations, of positive or negative kind.

Computer-controlled production of prosthetic constructions in the dental office – what are the quality requirements? -

With equipment for computer-aided design and manufacturing (CAD/CAM) in the dental office, the dentist again becomes his own dental technician. While the equipment itself is not subject to health-related regulation, the European Medical Devices Directive imposes requirements on the prosthodontic devices it produces

Appropriate eye protection filters prevent ocular damage -

A study was performed to assess 13 different eye protection filters, glasses and shields, intended for use with dental material light curing procedures as a follow- up to a similar investigation in 200

Chitosan – antibacterial use in dental materials -

Chitosan is produced commercially from crab and shrimp shell wastes with different degrees of deacetylation and molecular masses. Because of chitosan’s promising biological activities, including non-toxicity and antimicrobial activity, it is used for a variety of purposes in food production, medicine, agriculture, cosmetics, and biotechnology.

Guidance on the Determination of Potential Health Effects of Nanomaterials Used in Medical Devices -

This Guidance addresses the use of nanomaterials in medical devices and provides information for risk assessors regarding specific aspects that need to be considered in the safety evaluation of nanomaterials. According to the EU Recommendation for the definition of a nanomaterial (Commission Recommendation 2011/696/EU, EC 2011) any particulate substance with at least one dimension in the size range between 1 and 100 nm is considered a nanomaterial.

Appropriate eye protection filters prevent ocular damage from curing light -

A study was performed to assess 13 different eye protection filters, glasses and shields, intended for use with dental material light curing procedures as a follow-up to a similar investigation in 2006. To assess the safety and efficiency, spectra of curing lamps and filters were measured using a spectroradiometric instrument and integrating sphere.

Fluorescence characterization of dental plaque by hyperspectral imaging -

The buildup of dental plaque is the first step towards the oral diseases caries and periodontitis. Identification of pathogenic substances and matrix components is of importance when choosing an appropriate treatment plan. Hyperspectral imaging combines spectral- and spatial information, providing new possibilities for precise optical characterization of biological tissue [1,2], including dental plaque.

Importerte og norskproduserte tanntekniske arbeider – får vi det vi bestiller? -

Det settes søkelyset på forhold man kan stå overfor ved valg av tannerstatninger, om det er forskjell på et arbeid som er laget i Norge kontra et arbeid som er produsert i utlandet. To ganger tidligere (2008, 2010) er forholdet mellom oppgitt og analysert sammensetning av legeringselementene på importarbeid blitt undersøkt ved NIOM.

Ceramic Crown Margin Curvatures’ Effect on Fracture Strength -

Despite the high fracture strength of modern dental core ceramics, fracture is a common cause of failure in clinical trials. Fracture origins are typically in the crown margin in the appoximal region where the margin curves upwards. The scientific evidence for optimal marginal design of preparation is limited. The aim was to use a clinically relevant test method to evaluate the effect on strength of the cervical margin’s curvature of ceramic crowns.

Effect of different surface treatments and adhesives on repair bond strength of resin composites after one and 12 months of storage using an improved microtensile test method. -

To evaluate the effect of surface treatments and bonding systems on the repair bond strength between composite materials after one and 12 months of storage, using an improved microtensile test method.

Sub-lethal Concentrations of HEMA alter Protein Expression in Human Monocytes -

Several in vitro studies have shown increased intracellular level of reactive oxygen species (ROS) after exposure to 2-hydroxyethyl methacrylate (HEMA), a commonly used monomer in resin-based dental materials. This study aimed to investigate the initial changes of the proteome in a human monocyte cell line after exposure to HEMA by using Stable Isotope Labelling with Amino Acids in Cell culture (SILAC).