Cell toxicity of methacrylate monomers-the role of glutathione adduct formation. -

Polymer-based dental restorative materials are designed to polymerize in situ. However, the conversion of methacrylate monomer to polymer is never complete, and leakage of the monomer occurs. It has been shown that these monomers are toxic in vitro; hence concerns regarding exposure of patients and dental personnel have been raised.

Experimental investigation of the effect of surface roughness on bone-cement-implant shear bond strength. -

Debonding of cemented bone implants is regarded as a major contributor to complications. The relationship between shear bond strength and surface roughness has been investigated, however there are inconsistencies in the trends reported in different studies.

Summary of: Side effects of external tooth bleaching: a multi-centre practice-based prospective study. -

The study was performed to assess the risk of at-home and in-office bleaching procedures, and to recognise potential predictors for side effects.
Bleaching treatment, irrespective of method, caused a high prevalence of side effects

Solubility and strength of zirconia-based dental materials after artificial aging -

The purpose of this study was to compare the flexure strength of zirconium dioxide materials designed for different sintering techniques before and after surface exposure to an acidic solution and to correlate the dissolution of the materials with strength data.

Clinically relevant evaluation of fracture strength of all-ceramic crowns -

Determination of fracture strength of different all-ceramic dental crown systems is not straight forward. Most in vitrotest methods induce contact damage at the loading point (crunch the crown-tests). Clinical failures, on the other hand, usually originate from cracks in the cervical margins. The aim of this study was to compare three all-ceramic systems using a test method that mimic clinical failure modes.

Ex tempore prepared superstaurated solutions of curcumin intended for aPDT -

A naturally occurring photosensitizer Curcumin (Cur) has already shown good in vitro bacterial phototoxicity.¹ ²1,2  However,low aqueous solubility and poor photolytic and hydrolytic stability limit the therapeutic application of Cur in antibacterial photodynamic therapy (aPDT). The concept of supersaturation was explored for enhancing the photodynamic effect of Cur. A supersaturated solution of Cur has already demonstrated […]

Hyperspectral imaging/reflectance spectroscopy of mouse oral tissue exposed to high intensity blue light. -

Oral tissues are exposed to optical radiation during various dental treatments and diagnostic methods. However, adverse effects are seldom addressed. Hyperspectral imaging (HSI) and visible near-infrared reflection spectroscopy (VNIRS) were used to observe oral tissue changes in mice exposed to blue light with respect to erythema (erythema index; EI) and pigmentation (melanin index; MI). Pigmented mice (C57BL/6N; ngroup = 3) were exposed on the tongue and the abdominal skin for control or left unexposed. Irradiation was performed with an LED intended for photopolymerisation of dental materials (λpeaks: 409/460 nm) with irradiance ≈ 2 W/cm2 and radiant exposure ≈ 120 J/cm2.

Antimicrobial photodynamic treatment of oral infections -

The increased occurrence of antibiotic resistance in general necessitates development of alternative antimicrobial drugs or methods. Further, certain cases of periodontitis respond poorly to conventional treatment. The principle of photodynamic therapy, currently used against certain cancers, may be a practical treatment modality for oral infections, presumably with low possibility for development of resistance. The treatment requires the presence of light-absorbing molecules (photosensitizer; PS) and irradiation with a light source emission that spectrally matches the light-absorption of the PS.

Safety of optical light sources in the dental clinic -

To inform operators and suppliers of curing/bleaching lamps, lasers and other optical instruments intended for oral applications about safe use. Further, to give references to relevant international guidelines and standards.

Clinically relevant fracture testing of all-ceramic crowns -

Fracture strength measured in vitro indicates that most all-ceramic crowns should be able to withstand mastication forces. Nevertheless, fractures are one of the major clinical problems with all-ceramic restorations. Furthermore, the fracture mode of all-ceramic crowns observed in clinical use differs from that found in conventional fracture strength tests. The aim of the present study was to develop and investigate a method that simulates clinical fracture behavior in vitro

Detection of leachables and cytotoxicity after exposure to methacrylate- and epoxy-based root canal sealers in vitro. -

Abstract Root canal sealing materials may have toxic potential in vitro depending on the cell line, cytotoxicity assay, material chemistry, and degree of polymer curing. The aims of the present study were to detect leaching components from epoxy- or methacrylate-based root canal sealers and to investigate the degree of cytotoxicity after exposure to extracts from […]

Biofilm formation on nanostructured hydroxyapatite-coated titanium -

Biofilm formation on medical devices is a common cause of implant failure, especially regarding implants that breach the epithelial tissue, so-called transcutaneous implants. Nanotechnology and the development of new nanomaterials have given the opportunity to design nanotextured implant surfaces. Such surfaces have been studied using various in vitro methods showing that nanosized features strongly benefit bone cell growth.

Effect of short LED lamp exposure on wear resistance, residual monomer and degree of conversion for Filtek Z250 and Tetric EvoCeram composites. -

The latest LED dental curing devices claim sufficient curing of restorative materials with short curing times. This study evaluates mechanical and chemical properties as a function of curing time of two commercial composite filling materials cured with three different LED lamps.

Surface modification of fiber reinforced polymer composites and their attachment to bone simulating material -

The purpose of this study was to investigate the effect of fiber orientation of a fiber-reinforced composite (FRC) made of poly-methyl-methacrylate (PMMA) and E-glass to the surface fabrication process by solvent dissolution. Intention of the dissolution process was to expose the fibers and create a macroporous surface onto the FRC to enhance bone bonding of the material

Osteoporosis and periodontal disease -

Primary osteoporosis signifies the loss of trabecular bone mass following menopause and is linked to decreased production of estrogen. The condition increases the risk of traumatic fractures of peripheral bones such as wrist or femur and compression fractures of the spine. The degree of osteoporosis is determined by assessing the mineral density of different skeletal bones. Jawbone, including the tooth supporting alveolar process, may also be affected by osteoporosis.

Supersaturation and supersaturated drug delivery systems to surpass the outher membrane barriers of Gram negative bacteria in antimicrobial photodynamic therapy (aPDT). -

Bacterial resistance towards antibiotics is increasing. Especially Gram negative (G-) pathogenic bacteria are responsible for serious nosocomial infections. Novel treatment strategies such as antimicrobial photodynamic therapy (aPDT) are needed to fight such infections.

Application of nanovehicles in preparations for antimicrobial photodynamic therapy (aPDT) -

Topical application is the preferred administration route of the photosensitizer (PS) in antimicrobial photodynamic therapy (aPDT), e.g. for the treatment of infections in the oral cavity or skin. The drug formulation should allow for a sufficient contact time between the preparation and tissue, a rapid release of PS, and a selective uptake of PS in bacteria.

Antibacterial effects of native and methacrylate modified chitosan -

Commercial resin-based composites are mainly composed of dimethacrylate-based monomers, such as triethyleneglycol dimethacrylate (TEGDMA), inorganic fillers and a coupling agent. Cured resinbased composites have no antibacterial effect against oral bacteria and half of all fillings replaced are because of new caries . Chitosan is a natural carbohydrate polymer derived from the deacetylation of chitin. Chitosan has been shown to have an inhibitor effect on the adherence of oral bacteria onto human tooth surfaces.

Dental monomers inhibit LPS-induced cytokine release from the macrophage cell line RAW264.7 -

Methacrylate monomers have been identified in aqueous extracts of freshly cured dental fillings. The hypothesis tested presently was that low concentrations of triethyleneglycol dimethacrylate (TEGDMA) and 2-hydroxyethyl methacrylate (HEMA) alone or in combination interfere with the LPS-induced release of cytokines from the macrophage cell line RAW264.7.

Solid dispersions for preparation of phototoxic supersaturated solutions for antimicrobial photodynamic therapy (aPDT) Studies on curcumin and curcuminoides L -

Curcumin is under investigation as a potential photosensitizer (PS) in antimicrobial photodynamic therapy (aPDT). The therapeutic potential of curcumin as a PS is limited by its low aqueous solubility, susceptibility to hydrolytic and photolytic degradation, and limited phototoxicity toward Gram negative (G-) bacteria.

Solid dispersions for preparation of phototoxic supersaturated solutions for antimicrobial photodynamic therapy (aPDT): Studies on curcumin and curcuminoides L -

Curcumin is under investigation as a potential photosensitizer (PS) in antimicrobial photodynamic therapy (aPDT). The therapeutic potential of curcumin as a PS is limited by its low aqueous solubility, susceptibility to hydrolytic and photolytic degradation, and limited phototoxicity toward Gram negative (G−) bacteria.