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Background: Previous studies concerning the effect of botulinum toxin in masseter muscle have mainly reported effects observed through inspection of facial features or differences in pain levels. One systematic review of studies utilizing objective measurements reported that long-term muscular effect of botulinum neurotoxin injections into masseter muscle was inconclusive. Objective: To evaluate the duration of reduced maximal voluntary bite force (MVBF) after botulinum toxin intervention. Methods: The intervention group was comprised of individuals seeking aesthetic treatment for masseter reduction (n = 20), the reference group (n = 12) comprised of individuals with no intervention. Intervention through 25 units of Xeomin® (Merz Pharma GmbH & Co KGaA, Frankfurt am Main, Germany) botulinum neurotoxin type A injected into the masseter muscles bilaterally (totalling 50 units). A reference group did not receive any intervention. MVBF was measured in Newtons using a strain gauge meter at the incisors and first molars. MVBF was measured at baseline, at 4 weeks, 3 months, 6 months, and after 1 year. Results: Both groups were similar in terms of bite force, sex and age at baseline. MVBF remained similar compared to baseline in the reference group. At 3 months, a significant reduction at all measurement points was observed in the intervention group; at 6 months, this reduction was no longer significant. Conclusion: A single intervention of 50 units of botulinum neurotoxin results in a reversible MVBF reduction of at least 3 months, although a visually discernable reduction may be more long-lasting.

The aim of the present study was to investigate whether titanium (Ti)-induced release of interleukin (IL)-1β acts through the assembly of the NACHT, LRR, and PYD domain-containing protein 3 (NLRP3) inflammasome. In addition, we examined whether particulate Ti or TiO2 activates the same intracellular pathways with the assembly of the NLRP3 inflammasome as Ti ions. Ti ions are known to induce IL-1β maturation and release by the formation of metal–protein aggregates. Wild-type THP-1 (wt.) cells and NLRP3− and ASC− (apoptosis-associated speck-like protein containing caspase recruitment domain (CARD)) knockdown cells were used in the experimental analyses. Macro- and nanoparticles (NPs) of both Ti and TiO2 were used as test agents. IL-1β release as a biomarker for inflammasome activation and cell viability was also analyzed. Periodate-oxidized adenosine triphosphate (oATP) was used to attenuate downstream signaling in NLRP3 inflammasome activation. Cellular uptake of Ti was examined using transmission electron microscopy. Cells exposed to the Ti-ion solution showed a dose-dependent increase in the release of IL-1β; conversely, exposure to particulate Ti did not result in increased IL-1β release. Cell viability was not affected by particulate Ti. Knockdown cells exposed to Ti showed a statistically significant reduction in the release of IL-1β compared with wt. cells (p

To systematize evidence on the efficacy of botulinum toxin type A (BTA) in the treatment of bruxism measured through bite force or electromyography (EMG) at the masseter muscle.Identification of relevant articles through databases PubMed, Web of Science, SCOPUS, Ovid and EBSCO and manual search were performed for sources from review articles. Studies scoring less than 3 on the Jadad Scale were excluded.Four articles were included after an exclusion of 333 articles. 3 articles measured EMG and 1 bite force. 1 article did not record a significant drop of activity, 1 article recorded reduction midway and at final endpoint. 2 articles recorded initial reduction, but a non significant difference at later follow up.The available research is inconclusive and does not show enough evidence that bruxism can be treated with BTA injections. However, promising results have been shown in individual studies and further research in this area is needed.

The aim of this study was to investigate the titanium (Ti) content of biopsies from patients with severe peri-implantitis or controls without Ti exposure.Peri-implantitis is considered to be an infectious disease, but recent studies have shown that Ti can aggravate inflammation in combination with bacterial products. The Ti content of peri-implantitis and periodontitis (controls) tissue is unknown.Thirteen patients referred for peri-implantitis and eleven for periodontitis treatment were included in the study. Disease severity was obtained from dental records. Biopsies were taken from both groups and chemically analysed with inductively coupled plasma mass spectrometry for Ti content. Additionally, two patients with peri-implantitis and two with periodontitis were recruited and their biopsies were analysed microscopically with light microscopy, transmission electron microscopy and scanning electron microscopy with element analysis to investigate the presence of particulate Ti.All patients lost one or more implants despite undergoing peri-implant or treatment. Peri-implantitis tissue contained significantly higher concentrations of Ti than control samples with a mean ± SD of 98.7 ± 85.6 and 1.2 ± 0.9 μg/g, respectively. Particulate metal was identified in peri-implantitis and control biopsies, but element analyses could confirm only the presence of Ti in peri-implantitis tissue.We showed that high contents of particulate and submicron Ti were present in peri-implantitis tissue. These high Ti contents in peri-implant mucosa can potentially aggravate inflammation, which might reduce the prognosis of treatment interventions.

Source at https://www.tannlegetidende.no/i/2021/6/m-372. Flere faktorer bidrar til å påvirke klinisk holdbarhet på sementerte tannrestaureringer. Fordi preparering av tannvev til en ekstrakoronal restaurering er irreversibel, er det utstrakt forskningsaktivitet for å finne metoder og teknikker for å minimere biologisk skade og utvikle nye biomaterialer som krever mindre avvirkning av tannvev. Derfor blir vi stadig bombardert med nye «bedre» eller «enklere» produkter som ofte markedsføres for utvidet bruk. Imidlertid er de vitenskapelige bevisene for hvordan sementen og sementeringsteknikker påvirker klinisk resultat over tid begrenset og ofte vanskelig å tolke. For å oppnå optimal retensjon av en sementert protetisk erstatning kreves innsikt i individuelle kliniske situasjoner, kunnskap om interaksjoner mellom forskjellige protesematerialer, sement- og tannvevstyper, og overholdelse av riktige arbeidsprosedyrer. Several factors contribute to the clinical durability of cemented dental restorations. Because dental tissue preparation for an extracoronal restoration is irreversible, there is extensive research activity to find methods and techniques to minimize biological damage and develop new biomaterials that require less preparation of dental tissue. We are therefore constantly bombarded with new «better» or «simpler» products that are often marketed for extended use. However, the scientific evidence for how the cement and cementing techniques affect clinical outcomes over time is limited and often difficult to interpret. Achieving optimal retention of a fixed dental prosthesis requires insight into individual clinical situations, knowledge of interactions between different prosthesis materials, cement and dental tissue types, and adherence to proper work procedures.

Inflammation and bone reduction around dental implants are described as peri-implantitis and can be caused by an inflammatory response against bacterial products and toxins. Titanium (Ti) forms agg ...

In the present study, amount of titanium (Ti) released into the surrounding bone during placement of implants with different surface structure was investigated. Quantification of Ti released during insertion from three different implants was performed in this ex vivo study. Jaw bone from pigs was used as model for installation of the implants and Inductively Coupled Plasma Atomic Emission Spectroscopy (ICP-AES) was used for analysis of the released Ti. Implant surface were examined with scanning electron microscopy (SEM), before and after the placement into the bone. Ti was abraded to the surrounding bone upon insertion of a dental implant and the surface roughness of the implant increased the amount of Ti found. Diameter and total area of the implant were of less importance for the Ti released to the bone. No visible damages to the implant surfaces could be identified in SEM after placement.

Background and Objective: Peri-implantitis is a destructive inflammatory process characterized by destruction of the implant-supporting bone. Inflammasomes are large intracellular multiprotein complexes that play a central role in innate immunity by activating the release of proinflammatory cytokines. Although inflammasome activation has previously been linked to periodontal inflammation, there is still no information on a potential association with peri-implantitis. The aim of this study was to examine cytotoxic and proinflammatory effects, including inflammasome activation, of metals used in dental implants, in an in vitro model, as well as from clinical tissue samples. Material and methods: Human macrophages were exposed to different metals [titanium (Ti), cobalt, chromium and molybdenum] in a cell-culture assay. Cytotoxicity was determined using the neutral red uptake assay. Cytokine secretion was quantified using an ELISA, and the expression of genes of various inflammasome components was analysed using quantitative PCR. In addition, the concentrations of interleukin-1β (IL-1β) and Ti in mucosal tissue samples taken in the vicinity of dental implants were determined using ELISA and inductively coupled plasma mass spectrometry, respectively. Results: Ti ions in physiological solutions stimulated inflammasome activation in human macrophages and consequently IL-1β release. This effect was further enhanced by macrophages that have been exposed to lipopolysaccharides. The proinflammatory activation caused by Ti ions disappeared after filtration (0.22 μm), which indicates an effect of particles. Ti ions alone did not stimulate transcription of the inflammasome components. The Ti levels of tissue samples obtained in the vicinity of Ti implants were sufficiently high (≥ 40 μm) to stimulate secretion of IL-1β from human macrophages in vitro. Conclusion: Ti ions form particles that act as secondary stimuli for a proinflammatory reaction.

In this paper, three case-studies on the Mesolithic quartz industry of eastern middle Sweden are presented. The region lacks flint sources, and the most common suitable mineral is quartz. Callahan (1987) studied lithic assemblages from the region and proposed a general model for the knapping sequences. In his ideal scheme, knapping started with freehand platform flaking, followed by platform-on-anvil, and ended with bipolar-on-anvil reduction. However, Callahan stated that, in practice, knapping did not always follow this proposed model. Recent studies presented in this article show that the quartz industry of eastern middle Sweden is in some instances more sophisticated.

Glorstad's article deals with many issues, circling around transport and communication during the early Mesolithic colonization of Norway. Most importantly, Glorstad questions the range and seagoin...

1 After a 1-year, extensive pine looper (Bupalus piniaria) outbreak, plots were laid out to study tree susceptibility to attack, and performance of Tomicus piniperda in pine trees suffering from varying levels of defoliation. 2 Tomicus piniperda was the dominating stem-attacking species among the primary stem colonizers, and 82% of all trees that died had been colonized by T. piniperda. 3 Beetle attacks primarily struck severely defoliated trees, i.e. trees that suffered from 90% to 100% defoliation. 4 Beetle attacks peaked in the second year after cessation of the outbreak, and suppressed trees were both more frequently attacked and more susceptible to beetle attack than intermediate and dominant trees. 5 Trees surviving beetle attacks carried more foliage than trees that did not survive the attacks. 6 A single year of severe defoliation is enough to render pine trees susceptible to secondary pests, such as T. piniperda.

The spread of Heterobasidion parviporum Niemela & Korhonen in roots of Norway spruce was studied in three unthinned first rotation stands of Norway spruce [Picea abies (L.) Karst.] on former agricultural land in south-western Sweden. Heterobasidion parviporum was inoculated at stump height into the trunk of 135 standing trees in a randomized block design. One year after inoculation, two-thirds of the trees were thinned out and one-third was left standing. Half of the stumps left by thinning were treated with spores of Phlebiopsis gigantea (Fr.) Jul and half were left untreated. The spread of H. parviporum was examined both 3 and 5 yrs after inoculation. The rate of spread of H. parviporum and the proportion of infected roots were found to be significantly higher in the root systems of the stumps than in those of the standing trees. Treatment with P. gigantea had no significant effect on the development of H. parviporum in the stumps. There was a tendency 5 yrs after inoculation, however, for a lower propo...

Long-term comparisons of frameworks at the implant or abutment level are not available, and knowledge of the clinical function of cobalt-chromium (Co-Cr) alloy frameworks is limited. Primarily, the aim of this study was to compare the 5-year clinical performance of frameworks with or without abutment connections to implants. Secondly, the outcomes of prostheses made from Co-Cr alloy with porcelain veneers to those made of commercially pure titanium (CP Ti) with acrylic veneers were compared.The test groups comprised patients treated with screw-retained fixed prostheses made at the implant level according to the Cresco method in either dental porcelain-veneered Co-Cr alloy (n = 15) or acrylic-veneered CP Ti (n = 25). A control group of 40 randomly selected patients were provided with prostheses made at the standard abutment level in CP Ti with acrylic veneers. For all patients, clinical and radiologic 5-year data were retrospectively collected and evaluated.Five-year implant cumulative survival rates (CSRs) were 98.6% and 97.6% for test and control groups, respectively (P.05). No major differences in bone level were demonstrated between the groups after 5 years (P.05). Significantly more complications occurred in the test groups compared to the control group (P.01), with the most common complications being mucositis and fracture of veneers.After 5 years, the clinical outcomes of implant-level prostheses made of porcelain-veneered Co-Cr or acrylic-veneered CP Ti seem comparable to acrylic-veneered titanium prostheses made at the standard abutment level regarding implant CSR and bone levels. However, more complications were registered in implant-level prostheses compared to the standard abutment-level prostheses.

The current Swedish regulations for medical alerts in health records were designed for paper records. Suggestions for computerized systems are now being investigated. A proposed model using three alert categories, graphically represented using three directions, probably combined with three severity levels is presented here. Up represents hypersensitivities, left/back represents alerting diagnosis and right/forward represents alerting current and planned treatments. A small qualitative user study of the alert classification model and some graphical representations of it was conducted. One main finding is that most respondents found the use of directions intuitive as a means of presenting categories. Context dependency, information overload, and future possibilities for automated alert-gathering are also discussed in the paper.