Abstract from Krister Grønliens lecture at symposium PDT-4. Human antimicriobial PDT. ESP-IUPB World Congress, Light & Life, Barcelona, Spain. August 25-30. 2019. Natural deep eutectic solvents (NADES) is a group of eutectics that is based solely on environmental-friendly (“Green”) components. These solvents have unique solubilizing properties; i.e. they are more polar than water but can […]

Abstract from Ellen Bruzells lecture at symposium MED-10 Dentistry. (Organized by Ellen Bruzell). ESP-IUPB World Congress, Light & Life, Barcelona, Spain. August 25-30. 2019. Dental personnel encounter a number of optical sources emitting a broad spectrum of wavelengths. Along with the usefulness, to various extents, of optical radiation in treatment and diagnostics, comes the risk […]

The study revealed major deficiencies for both Norwegian and overseas made crowns regarding conformity between composition and the stated declaration

Surface modifications in the nanoscale regime have shown promising potential in the combat against bacterial adhesion and colonization of surfaces. However, detailed knowledge of how the bacteria–substrate interactions occur is still limited.

The function and durability of Implant based rehabilitation of the dentition has proved to be comparable to traditional prosthodontics. However, loss of implants do take place from time to time as the result of inadequate osseointegration or as the result of peri-implantitis. In addition to methodological and materials related subjects research in this field has […]

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.

The article describe the distribution of enamel-, dentin-, root- and secondary caries within an elderly population in Northern-Norway.

The aim is to compare the adhesion between zirconia and cements attained with melt-etching with potassium hydrogen difluoride, KHF2, with that found when such traditional surface treatments as sandblasting and ceramic stone grinding are employed.

When dentists are treating children with dental caries or DDDs, they must decide the most appropriate treatment in each case. The results of the present study showed a notable disparity between clinician’s
treatment choices. In summary, the clinicians based their treatment choice mostly on patient cooperation, prognosis of the tooth and own experience. The results indicate that Norwegian dentists in PDS evaluate each case individually and base their decisions on what they consider is the best for the individual child.

There is no standard treatment for damages caused by erosive tooth wear, and choice of treatment strategy should be determined on individual basis with emphasis on the minimal invasive intervention.

Résumé/implication clinique Le concept de réparation des restaurations défectueuses (plutôt que leur remplacement complet) fait partie des points clés de l’intervention minimale en cariologie. Cet article présente les résultats d’une enquête par questionnaire évaluant les attitudes cliniques et les connaissances en matière de prise en charge des restaurations défectueuses réalisée auprès d’une population de chirurgiens-dentistes […]

Dental health care professionals have the opportunity to play a key role in tobacco prevention and cessation among adolescents. Snus use has increased in Norway, especially in the age group 16–24, whereas there has been a decline in smoking. This study investigated attitudes and activities related to snus prevention among dental health care professionals working in the Public Dental Service (PDS) in south‐eastern Norway.

The results of this study show that CH-MA (CH-MA) may be incorporated into a composite and into an adhesive to reduce biofilm formation on their surfaces. The mechanical properties of the composite were challenged, but flexural strength measurements still met the requirement set in ISO 4049, whereas no differences were observed for the bonding properties of the adhesives.

To determine the thermal expansion of a porcelain (VM9) and tetragonal zirconia (Y-TZP) as well as the deflection upon re-heating and cooling of a bilayer fabricated from these two materials after slow and rapid cooling during initial fabrication.

This chapter in “Textbook and Color Atlas of Traumatic Injuries to the teeth” focuses on the treatment of discolored traumatized teeth, most of them being non‐vital and subsequently, endodontically treated. Tooth bleaching based upon hydrogen peroxide as the active agent, applied directly or produced in a chemical reaction from sodium perborate or carbamide peroxide, must […]

To evaluate debonding mechanism of zirconia and lithium disilicate cemented to dentin mimicking what could occur in a clinical setting. A null hypothesis of no difference in tensile bond strength between groups of zirconia and lithium disilicate cemented with resin cements was also tested.

Resin-based biomaterials are widely used in medical and dental treatment, and both clinicians and patients are exposed to the materials.
The present approach to analyzing the toxic potential of HEMA yielded information on interactions with living cells is not previously reported. This detailed information is of great value to make better predictions of possible side effects in the clinic.

Uttak av farge til fyllinger, kroner, broer og proteser av alle slag, er ofte en frustrerende øvelse. Men fortvil ikke, det ser ut til at de som praktiserer fargeuttak ofte og øver jevnlig, blir gode, uansett alder. Øvelse gjør mester

The purpose of this study was to compare the bleaching effects of peroxide-free and peroxide-containing tooth whitening products.
After 8 months, no perceivable lightening was noted for the peroxide-free products whereas the teeth treated with peroxide containing bleaching remained lightened.

The results of this study show that methacrylated chitosan (CH-MA) may be incorporated into a composite and into an adhesive to reduce biofilm formation on their surfaces. The mechanical properties of the composite were challenged, but flexural strength measurements still met the requirement set in ISO 4049, whereas no differences were observed for the bonding properties of the adhesives.

The airways of dental personnel can be exposed to low concentrations of HEMA on a daily basis. Thus, we aimed to explore altered gene expression in a bronchial epithelial cell line after exposure to “non-lethal” concentrations of HEMA, demonstrated to be 2 mM or below in the current model system. We show that the expression of a number of genes was altered in HEMA exposed cells.

Interest in dental erosive wear is increasing, and new recommendations of less invasive approaches to the treatment of the condition are emphasized. Therefore, the main objective of the present study was to identify dentists’ knowledge, beliefs, and clinical behaviour toward the condition. The present study is the first of its nature to analyze and permit comparison of the knowledge and treatment decisions of dental erosive wear between different countries, as it is conducted in a similar manner as the recent questionnaire study from Norway. The importance of making such intercountry assessments is high.

Amalgam restorations of adequate standard and condition can very well be repaired with composite, but there should be provided for extra retention into the amalgam filling as the bond strength alone is not adequate. Glass-Ionomer may also be used for repair at amalgam restoration margins in not stress bearing areas, but as they do not adhere to amalgam, they need enamel and dentine for retention and possible undercuts towards amalgam interface.

The present study was part of the research project Inhalation and prenatal exposure to phthalates: influence on airway immunology, conducted at the Norwegian Institute of Public Health, and was funded by the Norwegian research council (Research grant number: 228129).

The adaptation of single-crown fixed dental prostheses (FDPs) is a subject of great interest in the research community. Many investigations have been published, and a variety of evaluation methods have been used to determine the fit accuracy of prosthetics.
Many of the methods required manual measurements of the gap between the restoration and the abutment. With the introduction of CAD/CAM techniques, digital tools started being used for evaluating the adaptation of FDPs.
In this study, a tabletop dental scanner was used. It is anticipated that in a clinical setting, an intraoral scanner is sufficient, at least for single-crown FDPs.

Oral biofilm‐associated diseases, such as caries and periodontitis, represent global public health challenges. The diseases develop as a result of dysbiosis of the oral microbiome. There is a long tradition in medicine for treating bacterial infections by the use of antibiotics. Unfortunately, biofilm bacteria are significantly less sensitive to antibacterial agents than are their planktonic counterparts. This property of biofilm challenges us in our daily work as dentists, and might explain why many oral prophylactic agents predicted to be efficacious in vitro, only show marginal effect in vivo.

Human experiments on dental erosion are unethical because of the irreversible loss of dental hard tissues when exposed to acids. Therefore, studies using animal models are of high importance since they represent clinical situations. Based on the present results it can beconcluded that cola drink (phosphoric acid, pH=2.27) exhibited higher erosive effect on mouse mandibular molars compared to sports drink (citric acid, pH=3.39). This new animal model of extrinsic dental erosion where lesions of different severity can be created is suitable for further studies that will improve our understanding of the disease. The present method with transversely ground molars observed in SEM allows a registration of erosive lesions and lesion depths in small teeth like mouse molars. Both studies on the salivary influence (e.g. by using knockout mice) and the studies on the effect of fluoride on development of erosive lesions are warranted.

Optimizing quality and safety of resin‐based materials need coherent strategies. Proper handling and polymerization increase the rate of conversion and thus minimize the content of residual monomers. Measures to reduce biofilm accumulation at the tooth‐restoration interface could prevent or reduce the most common reason for restoration failure, recurrent caries.

New dimethacrylate monomer Bis-EFMA was synthesized and used to prepare Bis-GMA-free dental resin and composite materials. Studies of the experimental materials showed that Bis-EFMA-based resin matrix and composite materials had improved properties compared to Bis-GMA-based resin matrix and composite materials, respectively. Compared with the commercial dental composite material Z250, Bis-EFMA-based composite showed similar or improved properties except for a lower FS after water immersion. Based on the presented results, Bis-EFMA has potential to be used in commercial dental composites.

Dementia is a common term for diseases of the brain expressed as the loss of cognitive abilities and activities of daily living. The most frequent reason is Alzheimer’s disease, followed by vasculary dementia, dementia with Lewy bodies and mixed types. The number of persons with dementia is increasing due to the aging population in the […]

Dental calculus is the result of mineralized biofilm containing traces of dietary components and oral microbial cells. On this basis, analyses of dental calculus in archeological skeletal material including teeth may reveal information on prehistorical diet and living conditions. Research of this kind has indicated the use of heat treated plant based diet already by […]

BPA has been reported to leach from some resin-based dental restorative materials and materials used for orthodontic treatment. To confirm and update previous findings, especially in light of the new temporary lower threshold value for tolerable daily BPA intake, leaching of BPA from 4 composite filling materials, 3 sealants and 2 orthodontic bonding materials were investigated.

Methacrylates are common constituents of resin-based biomaterials. These materials cure by polymerization of methacrylate monomers, but incomplete polymerization causes leakage and patient exposure to the electrophile monomers.

For kort herdetid kan føre til mangelfull herding (polymerisasjon) av komposittmaterialer. For lang herdetid kan øke risiko for varmeskade på oralt bløtvev og pulpa. Herdelampens lysstyrke (irradians) reduseres når avstanden øker mellom lysutgangen og materialflaten.
For å opprettholde lysdosen som kreves for tilstrekkelig herding, må herdetiden økes. Kortere lysherdingstider enn omtrent 10 sekunder kan føre til utilstrekkelig herding av materialet.

The work at a dental clinic implies getting in contact with different chemical substances, which may cause temporary or permanent injury to the staff, primarily allergic reactions, but also local irritation, carcinogenic or toxic effects. Dentists and dental assistants belong to the professional groups most frequently experiencing work-related eczema.

To our knowledge, this is the first study to separate patients into more discrete groups based on dental caries experience defined from longitudinal data and the first to study acute increases in DMFT score between two time points. Our hope with doing so is to provide more power in our predictions of genetic influences of dental caries and perhaps lead to better ways of studying the disease based on more specific categorizations of phenotypes.

All dental restorations have a limited lifespan and will eventually need to be repaired or replaced. It is important to have in mind that the longevity of gold restorations have not been shown to be superior to that of resin composite, which should still be the first material of choice. However, gold inlays could be considered when the right indications are present.

Taste and smell are senses reacting upon solutes from food and breathing air conveyed by the cranial nerves. Normal aging includes cellulary and extracellulary biochemical mechanisms detrimental to neurons in the central nervous system, including those processing taste and smell signals. Aging also means reduction of the number of taste buds in the oral cavity and of the number of odor receptors in the nasal mucosa.

Antibacterial activity of 4 endodontic sealers against bacteria planktonic grown or in biofilms commonly detected from persistent and secondary endodontic infections.
Investigating the antibacterial activity of endodontic sealers and materials against bacteria in biofilms is highly important to evaluate the materials’ ability to eradicate bacteria from the infected root canal

Caries decline in the western world is accompanied by strong polarization among children; 8% of Finnish 5-year-olds having 76% of untreated caries. This high caries risk group needs preventive and restorative strategies.
Severely affected primary molars of children at high caries risk are better managed, using PMCs to optimize the resources in public oral health services.