Assessment of pH Value and Release of Calcium Ions in Calcium Silicate Cements: An In Vitro Comparative Study.

The goal of this study was to evaluate the pH and the release of calcium from four calcium-silicate-based cements. METHODS: Four materials were tested (ProClinic MTA; Angelus MTA; ProRoot MTA; Biodentine). The palatal canal root of acrylic upper molars was filled with each cement. Afterwards, they were set in phosphate-buffered saline. Measurements were taken by atomic adsorption spectroscopy (AAS) at 3, 24, 72, 168, 336, 672, and 1008 h. The pH was measured at the same timepoints. Kruskal-Wallis tests were carried out in each period, as the Kolmogorov-Smirnov and Shapiro-Wilk tests showed no parametric results. RESULTS: Significant differences (p < 0.05) in calcium release were found at the 3-, 24-, and 72-hour evaluations. All of the analyzed groups presented a release of calcium ions up to 168 h, and the general tendency was to increase up to 672 h, with a maximum release of 25.45 mg/g in the ProRoot group. We could only observe significant differences (p < 0.05) in pH value over 168 h between the Biodentine (7.93) and Angelus MTA (7.31) groups. CONCLUSIONS: There were significant differences (p < 0.05) in calcium release. Nevertheless, no significant differences (p > 0.05) in the pH values were found at the studied timepoints, except for the values at 168 h.

Assessment and Improvement of Masticatory Performance in Frail Older People: A Narrative Review.

According to the World Health Organization (WHO), the estimated number of older adults is around 962 million and is projected to increase to 2.1 billion by 2050. The oral frailty concept is associated with gradual oral function loss in relation to aging. There is a need to emphasize the improvement of oral function based on an evaluation of masticatory performance in patients with various oral conditions or systemic diseases and especially in the frail elderly. The present narrative review presents an overview of the current state of the assessment and improvement of masticatory performance in frail older people. To fully encompass oral frailty, oro-facial hypofunction, or oro-facial fitness, dental Patient Reported Outcomes (dPROs) should be included; nevertheless, there are limited evidence-based rehabilitation approaches. The concept of oral frailty, oro-facial hypofunction, or oro-facial fitness should involve dental Patient Reported Outcomes (dPROs), and in this sense, there are only a few evidence-based rehabilitation procedures to improve oro-facial hypofunction besides prosthodontics. It must be considered that reduced neuroplastic capacity in old individuals might preclude a positive outcome of these strategies that might need to be accompanied by functional training and nutritional counseling.

Titanium-base abutments may have similar long-term peri-implant effects as non-bonded one-piece abutments.

Design A single-centre (private practice), prospective, longitudinal, split-mouth, single-blind, randomised controlled clinical trial reported peri-implant parameters of individualised abutments bonded to titanium (Ti) bases during a five-year follow-up. The study complied with the ethical principles of the Helsinki Declaration and the CONSORT (Consolidated Standards of Reporting Trials) guidelines. It was approved by the Medical Ethical Committee of the University of Freiburg (013/1630) and registered in the German Clinical Trials Register (DRKS00006163).Case selection The included subjects had to be over 17 years of age, have an American Society of Anaesthesiologists score of 1, be a non-smoker, have a full-mouth plaque index (PI) below 20%, full-mouth bleeding index (BI) 20%, and planned with at least two dental implants but not adjacent to each other. Participants were excluded if they required simultaneous augmentation, were pregnant or breastfeeding, or had a history of periodontitis. Marginal bone loss (MBL) was the main clinical outcome, while local bleeding on probing (BoP), probing pocket depth (PPD), plaque Index (PI), local recession (REC), and relative attachment level (RAL) were also evaluated. The study timeline consisted of a screening (visit 1) and implant surgery (visit 2). Stage two was three months after implant surgery (visit 3), impression was two weeks after stage two (visit 4), followed up by baseline with a standardised radiograph (visit 5), one-year follow-up with radiographic and clinical parameters (visit 6), two-year follow-up (visit 7), three-year follow-up (visit 8), four-year follow-up (visit 9) and five-year follow-up (visit 10). In total, 24 subjects received two bone-level implants (Conelog, Camlog Biotechnologies, Basel, Switzerland) in the same arch and region up to 1 mm subcrestally. Their implant-abutment connection was an internal 7.5 degree conical connection platform-switch. Each subject received two abutments (one control and one test) as per the split-mouth design. The control abutments consisted of individualised, one-piece, computer-aided design/computer-aided manufacturing (CAD/CAM) titanium abutments, whereas the test abutments were CAD/CAM titanium abutments bonded to Ti-bases. The decision which implant was restored and in which way was made by a coin flip. The surgeon, patient and prosthodontist were blinded regarding the treatment allocation.Data analysis Descriptive measures and quantitative parameters were obtained from means, standard deviations, minimum and maximum values and 95% confidence intervals. The means of clinical parameters (six sites per implant) were MBL, BoP, PPD, PI, REC, and RAL. Paired t-tests were used for intragroup comparisons at different intervals as well as for intergroup comparisons within each time point. All data collected were considered until participants dropped out (that is, intention-to-treat principle). The significance level alpha was set to 0.05. The post-hoc power calculation of the MBL intergroup comparison dammed this trial as underpowered (power = 34%).Results All implants were osseointegrated after the healing stage and no implants were lost during the trial. Two subjects dropped out (one after the two-year follow-up and the other at the last appointment). Regarding MBL, no significant intergroup differences were found between the abutment groups. Nonetheless, significant intragroup differences were found at several visits (visit 6 to visit 10) compared to the baseline MBL (visit 5), indicating continuous bone level alterations. Concerning the BoP, no significant differences were identified. In terms of PPD, significant intergroup differences were found at visits 9 (p = 0.006) and 10 (p = 0.024), favouring Ti-base abutments. There were significantly intergroup differences in terms of REC (p = 0.014) at visit 10, with higher values in the one-piece abutment group. No differences were found in terms of PI.Conclusions A preliminary conclusion of this underpowered trial was that Ti-base abutments have a similar long-term effect to one-piece abutments on human peri-implant tissues.

Occurrence and outcome of firework-related ocular injuries in Switzerland: A descriptive retrospective study.

BACKGROUND: Firework-related ocular injuries (FWROI) are a major cause of preventable visual impairment. This study aimed to analyze the occurrence and outcome of FWROI in Switzerland. METHODS: This retrospective multicenter study included patients with FWROI from seven centers in Switzerland from January 2009 to August 2020. Demographic information, type of injuries, medical and surgical treatments, the best corrected visual acuity (BCVA) at baseline and end of follow-up, occurrence and type of secondary complications, and duration of hospitalization were analyzed. RESULTS: A total of 105 patients (119 eyes) with a mean age of 27.1 ± 15.9 years were included in the study (71.4% male patients; 29.5% underage). Most injuries occurred around New Year's Eve (32.4%) and the Swiss national holiday on 1 August (60.9%). The most common anterior segment findings were conjunctival or corneal foreign bodies (58%), whereas Berlin's edema was the most common posterior segment finding (11.4%). Globe ruptures were found in four patients. The mean BCVA in all patients at first presentation was 0.4 ± 0.8 logMAR and improved to 0.3 ± 0.8 logMAR at last follow-up. A primary surgical intervention was performed in 48 eyes (40.3%). Hospitalization directly after the trauma was necessary for 18 patients for a mean of 5.8 ± 4.1 days, and a total of 4.9 ± 7.6 follow-up visits were needed. CONCLUSION: This study provides the first data on FWROI in Switzerland, which are helpful for further preventive and educational programs and comparisons with other countries.

Agreement of intraocular lens power calculation between 2 SS-OCT-based biometers.

PURPOSE: To assess agreement of measurements by 2 swept-source optical coherence tomography biometers and to evaluate the prediction error (PE) in intraocular lens power calculation with 7 formulas. SETTING: Tertiary public eye hospital. DESIGN: Consecutive observational. METHODS: Axial length (AL), keratometry (K), anterior chamber depth (ACD), lens thickness (LT), and corneal diameter (CD) were measured with the IOLMaster 700 (Biometer A) and Anterion (Biometer B). Agreement was quantified by the limits of agreement and concordance correlation coefficient (CCC). The PE, the median absolute error, and the mean absolute error of the Barrett Universal II, EVO 2.0, Haigis, Hoffer Q, Holladay 1, Kane, and SRK/T formulas were investigated after constant optimization. RESULTS: In 78 eyes from 78 patients, excellent agreement was obtained for AL (CCC >0.99), very good agreement for K, ACD, and LT (CCC >0.95), and strong agreement for CD (CCC >0.72). An additive offset of 0.07 mm was measured for ACD and LT whose mean values were higher with Biometer B (P < .001). No statistically significant difference was found between the PEs and their absolute values when comparing the results of each formula between the 2 biometers. CONCLUSIONS: Agreement of biometric measurements by the 2 biometers was high, although Biometer B provided higher mean values of ACD and LT by 0.07 mm. In cataract patients with normal eye length, measurements by the 2 biometers did not lead to different refractive outcomes with the 7 formulas investigated.

Relative amount of tooth structure removal in different partial- and full-crown preparation designs.

PURPOSE: To assess the effect of tooth morphology on the amount of tooth structure removal and the effect of different assessment methods on the detected amount of removed tooth structure. MATERIALS AND METHODS: Eight test groups (n = 10) of standardized artificial teeth were prepared for partial and full crowns. All teeth were prepared by the same operator following predefined preparation parameters. Tooth structure removal was measured using three different assessment methods: digital volumetric analysis (DVA), weight analysis (WA), and combined computer-aided manufacture and weight analysis (CAMWA). Nonparametric repeated-measures analysis of variance and post hoc analyses were used to determine the influence of tooth morphology and assessment method on the detected amount of tooth structure removal. RESULTS: For partial crown preparations, only the tooth morphology had a significant impact on the detected amount of tooth structure removal (P < .0001), not the different assessment methods used (P = .08). Tooth structure removal was not significantly different between the canine and incisor groups, but was for the other groupwise comparisons. For full crown preparations, the tooth morphology (P = .047) and different assessment methods (P = .01) had an impact on the detected tooth structure removal. However, only a few groupwise comparisons reached the significance level. CONCLUSION: The amount of tooth structure removal depended on the tooth morphology and the type of assessment method, which should be taken into account when comparing results across studies. The detected amount of tooth structure removal was below the values described in the literature, independent of the assessment method used.

Systemic AAV6-synapsin-GFP administration results in lower liver biodistribution, compared to AAV1&2 and AAV9, with neuronal expression following ultrasound-mediated brain delivery.

Non-surgical gene delivery to the brain can be achieved following intravenous injection of viral vectors coupled with transcranial MRI-guided focused ultrasound (MRIgFUS) to temporarily and locally permeabilize the blood-brain barrier. Vector and promoter selection can provide neuronal expression in the brain, while limiting biodistribution and expression in peripheral organs. To date, the biodistribution of adeno-associated viruses (AAVs) within peripheral organs had not been quantified following intravenous injection and MRIgFUS delivery to the brain. We evaluated the quantity of viral DNA from the serotypes AAV9, AAV6, and a mosaic AAV1&2, expressing green fluorescent protein (GFP) under the neuron-specific synapsin promoter (syn). AAVs were administered intravenously during MRIgFUS targeting to the striatum and hippocampus in mice. The syn promoter led to undetectable levels of GFP expression in peripheral organs. In the liver, the biodistribution of AAV9 and AAV1&2 was 12.9- and 4.4-fold higher, respectively, compared to AAV6. The percentage of GFP-positive neurons in the FUS-targeted areas of the brain was comparable for AAV6-syn-GFP and AAV1&2-syn-GFP. In summary, MRIgFUS-mediated gene delivery with AAV6-syn-GFP had lower off-target biodistribution in the liver compared to AAV9 and AAV1&2, while providing neuronal GFP expression in the striatum and hippocampus.

Root-retained overdentures: Survival of abutment teeth with precision attachments on root caps depends on overdenture design.

BACKGROUND: Root-retained overdentures (OD) are one treatment option for partially edentulous patients. However, the available evidence regarding factors influencing abutment survival in root-retained ODs is limited. PURPOSE: This retrospective study included clinical examinations and evaluated the survival rate of roots restored with precision attachments soldered to post-and-core (gold cap) retained ODs, analysed with respect to various patient- and prosthesis-related factors. METHODS: Patients receiving at least one OD with gold caps in the past were invited for comprehensive clinical examinations. The primary outcome parameter was the abutment survival rate over the observation period (2002-2016). Possible contributing factors (eg closed vs open OD design) were analysed. Analyses included Kaplan-Meier estimators, Cox regressions and hazard ratios (HR). RESULTS: 114 patients with 128 ODs originally retained by 280 abutments, with a cumulative total exposure time of 2035.4 years, were examined. Twenty-seven abutment teeth (9.6%) were lost after a mean observation period of 7.9 ± 3.4 years. Significant factors associated with abutment loss were a closed, compared to an open OD design (HR 8.38 (95% CI 1.11-63.59), P = .040), which was independent of the number of abutments per OD. Furthermore, the loss rate was higher when the denture was not worn day-and-night (HR 3.52 (95% CI 1.32-9.40), P = .012). Oral hygiene behaviour was associated with higher HRs. CONCLUSIONS: ODs remain a viable treatment option for patients with few teeth remaining in the dental arch. It is advisable to choose an open design for the OD, irrespective of the number of abutment teeth. Furthermore, gold cap-retained ODs should not be removed overnight.

Neonatal outcomes in singleton pregnancies conceived by fresh or frozen embryo transfer compared to spontaneous conceptions: a systematic review and meta-analysis.

PURPOSE: The use of assisted reproductive technology (ART) has increased in the last 2 decades and continuous surveillance is needed. This systematic review aims to assess the risk of adverse neonatal outcomes (preterm birth [PTB], low birth weight [LBW], small-for-gestationalage [SGA] and large for gestational-age [LGA]), in singleton pregnancies conceived by fresh or frozen embryo transfer (FET) compared to spontaneous conceptions. METHODS: Cohort studies were identified from MEDLINE, Embase, Cochrane Library (January 2019), and manual search. Meta-analyses were performed to estimate odds ratios (OR) using random effects models in RevMan 5.3 and I-squared (I2) test > 50% was considered as high heterogeneity. RESULTS: After 3142 titles and abstracts were screened, 1180 full-text articles were assessed, and 14 were eligible. For fresh embryo transfer, the pooled ORs were PTB 1.64 (95% CI 1.46, 1.84); I2 = 97%; LBW 1.67 (95% CI 1.52, 1.85); I2 = 94%; SGA 1.46 [95% CI 1.11, 1.92]; I2 = 99%, LGA 0.88 (95% CI 0.80, 0.87); I2 = 80%). For frozen, the pooled ORs were PTB 1.39 (95% CI 1.34, 1.44); I2 = 0%; LBW 1.38 (95% CI 0.91, 2.09); I2 = 98%; SGA 0.83 (95% CI 0.57, 1.19); I2 = 0%, LGA 1.57 (95% CI 1.48, 1.68); I2 = 22%). CONCLUSIONS: When compared with spontaneous pregnancies, fresh, but not frozen was associated with LBW and SGA. Both fresh and frozen were associated with PTB. Frozen was uniquely associated with LGA. Despite improvements in ART protocols in relation to pregnancy rates, attention is needed towards monitoring adverse neonatal outcomes in these pregnancies.

Strategy to enhance transgene expression in proximity of amyloid plaques in a mouse model of Alzheimer's disease.

Gene therapy can be designed to efficiently counter pathological features characteristic of neurodegenerative disorders. Here, we took advantage of the glial fibrillary acidic protein (GFAP) promoter to preferentially enhance transgene expression near plaques composed of amyloid-beta peptides (Aß), a hallmark of Alzheimer's disease (AD), in the TgCRND8 mouse model of amyloidosis. Methods: The delivery of intravenously injected recombinant adeno-associated virus mosaic serotype 1/2 (rAAV1/2) to the cortex and hippocampus of TgCRND8 mice was facilitated using transcranial MRI-guided focused ultrasound in combination with microbubbles (MRIgFUS), which transiently and locally increases the permeability of the blood-brain barrier (BBB). rAAV1/2 expression of the reporter green fluorescent protein (GFP) under a GFAP promoter was compared to GFP expression driven by the constitutive human beta actin (HBA) promoter. Results: MRIgFUS targeting the cortex and hippocampus facilitated the entry of rAAV1/2 and GFP expression under the GFAP promoter was localized to GFAP-positive astrocytes. Adjacent to Aß plaques where GFAP is upregulated, the volume, surface area, and fluorescence intensity of the transgene GFP were greater in rAAV1/2-GFAP-GFP compared to rAAV1/2-HBA-GFP treated animals. In peripheral organs, GFP expression was particularly strong in the liver, irrespective of the promoter. Conclusion: The GFAP promoter enhanced transgene expression in proximity of Aß plaques in the brain of TgCRND8 mice, and it also resulted in significant expression in the liver. Future gene therapies for neurological disorders could benefit from using a GFAP promoter to regulate transgene expression in response to disease-induced astrocytic reactivity.

Association between osteoarthritis and increased risk of dementia: A systemic review and meta-analysis.

OBJECTIVE: To investigate the possible association between osteoarthritis (OA) and the risk of dementia. METHODS: Cohort, case-control, and cross-sectional studies were obtained from wide literature search up to 20 April 2018 from following electronic databases: PubMed, Embase, Cochrane, using the MeSH terms: "osteoarthritis" AND "dementia". The literature search was then expanded to congress abstracts. After screening and selection of relevant studies by two investigators, data was extracted. Estimates were then calculated using a random-effect size model. Sensitivity-analysis was conducted for gender and age adjusted studies and pooled for studies with STROBE quality assessment score ≥75%. Publication bias was assessed by Funnel plot. Analyses were performed using Data Analysis and Statistical Software Version 14.2. RESULTS: Nearly 1549 publication references were initially retrieved. Twenty-six publications were checked with full-text. Six observational studies with 388,252 individuals were included. OA was associated with a significantly increased risk for dementia (OR = 1.20; 95% confidence interval (CI), 1.03-1.39, I = 95.6%, P < .05). After pooling the studies with adjustment of age and gender, the risk increased (OR 1.36; 95% CI, 1.22-1.51, I = 75.6%, P < .0001). After pooling the study with a STROBE Quality score ≥75% the risk for dementia was slightly increased (OR 1.33; 95% CI, 1.17-1.5, I = 93.5%, p < 0.0001). CONCLUSIONS: There is an association between osteoarthritis and the risk of dementia. This meta-analysis does not provide causality. Further prospective cohort studies are needed to clarify, if knee-, hip-, or hand-OA are independent risk factors for Alzheimer's disease and vascular dementia.

Do immune cells lead the way in subchondral bone disturbance in osteoarthritis?

Osteoarthritis (OA) is a whole-joint disorder, and non-cartilage articular pathologies, e.g. subchondral bone disturbance, contribute substantially to the onset and progression of the disease. In the early stage of OA, abnormal mechanical loading leads to micro-cracks or micro-fractures that trigger a reparative process with angiogenesis and inflammatory response. With the progression of disease, cystic lesion, sclerosis and osteophytosis occur at tissue level, and osteoblast dysfunction at cellular level. Osteoblasts derived from OA sclerotic bone produce increased amount of type I collagen with aberrant Col1A1/A2 ratio and poor mineralization capability. The coupling mechanism of bone resorption with formation is also impaired with elevated osteoclastic activities. All these suggest a view that OA subchondral bone presents a defective fracture repair process in a chronic course. It has been found that T and B cells, the major effectors in the adaptive immunity, take part in the hard callus formation at fracture site in addition to the initial phase of haematoma and inflammation. Infiltration of lymphocytes could interplay with osteoclasts and osteoblasts via a direct physical cell-to-cell contact. Several lines of evidence have consistently shown the involvement of T and B cells in osteoclastogenesis and bone erosion in arthritic joints. Yet the biological link between immune cells and osteoblastic function remains ambiguous. This review will discuss the current knowledge regarding the role of immune cells in bone remodelling, and address its implications in emerging basic and clinical investigations into the pathogenesis and management of subchondral bone pathologies in OA.

Functional Amyloids and their Possible Influence on Alzheimer Disease.

Amyloids play critical roles in human diseases but have increasingly been recognized to also exist naturally. Shared physicochemical characteristics of amyloids and of their smaller oligomeric building blocks offer the prospect of molecular interactions and crosstalk amongst these assemblies, including the propensity to mutually influence aggregation. A case in point might be the recent discovery of an interaction between the amyloid ß peptide (Aß) and somatostatin (SST). Whereas Aß is best known for its role in Alzheimer disease (AD) as the main constituent of amyloid plaques, SST is intermittently stored in amyloid-form in dense core granules before its regulated release into the synaptic cleft. This review was written to introduce to readers a large body of literature that surrounds these two peptides. After introducing general concepts and recent progress related to our understanding of amyloids and their aggregation, the review focuses separately on the biogenesis and interactions of Aß and SST, before attempting to assess the likelihood of encounters of the two peptides in the brain, and summarizing key observations linking SST to the pathobiology of AD. While the review focuses on Aß and SST, it is to be anticipated that crosstalk amongst functional and disease-associated amyloids will emerge as a general theme with much broader significance in the etiology of dementias and other amyloidosis.

The human brain endothelial barrier: transcytosis of AAV9, transduction by AAV2: An Editorial Highlight for 'Trafficking of adeno-associated virus vectors across a model of the blood-brain barrier; a comparative study of transcytosis and transduction using primary human brain endothelial cells'.

Read the highlighted article 'Trafficking of adeno-associated virus vectors across a model of the blood-brain barrier; a comparative study of transcytosis and transduction using primary human brain endothelial cells' on page 216.

Communication: molecular dynamics and (1)H NMR of n-hexane in liquid crystals.

The NMR spectrum of n-hexane orientationally ordered in the nematic liquid crystal ZLI-1132 is analysed using covariance matrix adaptation evolution strategy (CMA-ES). The spectrum contains over 150 000 transitions, with many sharp features appearing above a broad, underlying background signal that results from the plethora of overlapping transitions from the n-hexane as well as from the liquid crystal. The CMA-ES requires initial search ranges for NMR spectral parameters, notably the direct dipolar couplings. Several sets of such ranges were utilized, including three from MD simulations and others from the modified chord model that is specifically designed to predict hydrocarbon-chain dipolar couplings. In the end, only inaccurate dipolar couplings from an earlier study utilizing proton-proton double quantum 2D-NMR techniques on partially deuterated n-hexane provided the necessary estimates. The precise set of dipolar couplings obtained can now be used to investigate conformational averaging of n-hexane in a nematic environment.