Ex-vivo recellularisation and stem cell differentiation of a decellularised rat dental pulp matrix

Implementing the principles of tissue engineering within the clinical management of non-vital immature permanent teeth is of clinical interest. However, the ideal scaffold remains elusive. The aim of this work was to assess the feasibility of decellularising rat dental pulp tissue and evaluate the ability of such scaffold to support stem cell repopulation. Rat dental pulps were retrieved and divided into control and decellularised groups. The decellularisation protocol incorporated a low detergent concentration and hypotonic buffers. After decellularisation, the scaffolds were characterised histologically, immunohistochemistry and the residual DNA content quantified. Surface topography was also viewed under scanning electron microscopy. Biocompatibility was evaluated using cytotoxicity assays utilising L-929 cell line. Decellularised scaffolds were recellularised with human dental pulp stem cells up to 14 days in vitro. Cellular viability was assessed using LIVE/DEAD stain kit and the recellularised scaffolds were further assessed histologically and immunolabelled using makers for odontoblastic differentiation, cytoskeleton components and growth factors. Analysis of the decellularised scaffolds revealed an acellular matrix with histological preservation of structural components. Decellularised scaffolds were biocompatible and able to support stem cell survival following recellularisation. Immunolabelling of the recellularised scaffolds demonstrated positive cellular expression against the tested markers in culture. This study has demonstrated the feasibility of developing a biocompatible decellularised dental pulp scaffold, which is able to support dental pulp stem cell repopulation. Clinically, decellularised pulp tissue could possibly be a suitable scaffold for use within regenerative (reparative) endodontic techniques

Prevalence of anxiety, sleep bruxism and temporomandibular disorders during COVID-19 in Qatari children and adolescents: a cross-sectional study

Purpose: Understanding the impact of coronavirus disease-2019 (COVID-19) pandemic social restrictions on the lives of children and adolescents is of utmost importance to enable timely diagnosis and treatment. Therefore, the aim of this study was to explore the prevalence of anxiety, sleep bruxism, temporomandibular disorders (TMD) and change in dietary and brushing habits and their association with COVID-19 social restrictions. Methods: Parents of fit and healthy Qatari children and adolescents were recruited and interviewed by the research team, whereby validated questioners were used to assess the prevalence of children’s/adolescents’ anxiety, sleep bruxism and TMD. Furthermore, changes in dietary and brushing habits were also evaluated. Results: A total of 199 parents of children and adolescents (mean age = 9.3 ± 3.2 years old) were included. Overall anxiety symptoms, sleep bruxism and TMD were evident in 29.6%, 5.7% and 23.1%, respectively. An increased consumption of food, sweets and worsening of brushing habits were evident in 51.8%, 62.8% and 31.2%, respectively. Conclusion: Within the limitations of this study, pandemic-related social restrictions could result in elevated levels of anxiety, specifically, social phobia, amongst children and adolescents, which could inevitably lead to unwanted dental consequences

Development of professional identity among dental students - A qualitative study

The study explored dental students' perception of their professional identity (PI) development at a newly established dental college with a problem-based learning (PBL) curriculum. Qualitative methods based on focus groups were used for data collection. The conceptual framework of the study was informed by a subject-centered sociocultural approach to PI development. Purposive sampling was used to collect data from five focus groups of undergraduate dental students to gain a deeper understanding of their PI development in a PBL environment. Out of a total of 38 dental students in years 2 and 3, 34 students (89.47%) participated in the focus groups. A theory-driven thematic analysis was used to dissect the views and experiences of the participants to explore factors contributing to PI development in the early years of the program. At an individual level, PBL was seen to be appropriate for PI development. However, some participants placed more emphasis on practical training in operative dental skills. Relational sources especially role modeling by the PBL facilitators and faculty staff were identified as a key factor to nurture PI development. Mixed views were observed on the value of PBL to enhance team-working skills. The participants also identified challenges of PBL and provided recommendations on further improvements to enhance the learning experiences of the students. This study provided useful insights into a PBL curriculum at a newly established dental institution. The findings underscore the value of PBL in developing PI and also highlight the challenges of implementing PBL in a socio-cultural context and pedagogical implications for further program improvement.The authors would like to thank all the student participants for their contribution to this research. Open access funding was provided by the Qatar National Library

Impact of opioid-free analgesia on pain severity and patient satisfaction after discharge from surgery: multispecialty, prospective cohort study in 25 countries

Background: Balancing opioid stewardship and the need for adequate analgesia following discharge after surgery is challenging. This study aimed to compare the outcomes for patients discharged with opioid versus opioid-free analgesia after common surgical procedures.Methods: This international, multicentre, prospective cohort study collected data from patients undergoing common acute and elective general surgical, urological, gynaecological, and orthopaedic procedures. The primary outcomes were patient-reported time in severe pain measured on a numerical analogue scale from 0 to 100% and patient-reported satisfaction with pain relief during the first week following discharge. Data were collected by in-hospital chart review and patient telephone interview 1 week after discharge.Results: The study recruited 4273 patients from 144 centres in 25 countries; 1311 patients (30.7%) were prescribed opioid analgesia at discharge. Patients reported being in severe pain for 10 (i.q.r. 1-30)% of the first week after discharge and rated satisfaction with analgesia as 90 (i.q.r. 80-100) of 100. After adjustment for confounders, opioid analgesia on discharge was independently associated with increased pain severity (risk ratio 1.52, 95% c.i. 1.31 to 1.76; P < 0.001) and re-presentation to healthcare providers owing to side-effects of medication (OR 2.38, 95% c.i. 1.36 to 4.17; P = 0.004), but not with satisfaction with analgesia (beta coefficient 0.92, 95% c.i. -1.52 to 3.36; P = 0.468) compared with opioid-free analgesia. Although opioid prescribing varied greatly between high-income and low- and middle-income countries, patient-reported outcomes did not.Conclusion: Opioid analgesia prescription on surgical discharge is associated with a higher risk of re-presentation owing to side-effects of medication and increased patient-reported pain, but not with changes in patient-reported satisfaction. Opioid-free discharge analgesia should be adopted routinely

An hybrid approach for the comparison of VAWT and HAWT performances for floating offshore wind turbines

This article describes the experimental comparison of the DTU 10MW HAWT with the WindQuest 10MW VAWT scaled models when both fitted on the Nautilus-10 semisubmersible. For the campaign in Ifremer Wind&Wave tank, different rotor representations are tested from inertia only to hybrid testing with propellers and a Software in the Loop. The hybrid testing uses a tabulated approach for thrust computation and is discussed in this article. The different thrust reproduction methods are compared to OpenFAST simulations calibrated during the Lifes50+ project and used as reference points. When quantifying the scale model's fidelity to Open Fast, cross-correlation was increased up to 14% with the use of the SiL. Thanks to the validation of hydrodynamic simulations based on experimental responses of the floater, it is shown that the VAWT rotor can be upscaled to 13MW for the same platform

Vital pulp treatment for traumatized permanent teeth: A systematic review

Background: Traumatic dental injuries involving the pulp are quite common and there is a need to evaluate the quality of evidence on the success of vital pulp treatment (VPT) interventions in traumatised permanent teeth. Objectives: The aim of this systematic review was to assess the success of VPT in the management of traumatised human vital permanent teeth diagnosed with complicated crown or crown-root fractures. Methods: An electronic search of the following databases: Web of Science, Scopus, PubMed, MEDLINE, EMBASE, LILACS, Clinical Trial Registries and the grey literature was performed until 25th/8/2021. Controlled clinical trials, cohort studies, case-control studies, case series with at least five cases and a minimum of 12-months follow-up were included. Non-English language literature was excluded. Two independent assessors performed study selection, data extraction and quality assessment using the National Institutes of Health’s quality assessment tool. Disagreements were resolved through consensus/with a third assessor. Results: A total of 14-studies (2-controlled clinical trials, 1-case-control, and 11-case series) published between 1978–2020, with a total of 1081 permanent teeth and an age range between 6–42 years-old were included. Bias analysis ranged considerably from ‘good’ to ‘poor’. Meta-analysis was not performed due to data heterogeneity, unclear reporting, and limited number of controlled clinical studies. Partial pulpotomy was the main reported clinical procedure with an overall success rate between 82.9–100%. Complete pulpotomy and direct pulp capping were associated with lower success rates of 79.4–85.7% and 19.5%, respectively. Calcium hydroxide was the main pulp capping material with favourable clinical and radiographic success (79.4–100%). Biodentine®, mineral trioxide aggregate and IRoot® BP were also associated with a high clinical and radiographic success, 80–91%, 80–100%, and 90–100%, respectively, albeit in fewer studies. Discussion: Although a high success rate has been reported when using VPT in managing pulpally involved traumatised teeth, the results of this systematic review clearly highlighted a paucity and low quality of the available evidence. Conclusions: Overall high success of VPT in the management of traumatised vital permanent teeth were reported, although based on limited evidence of well-conducted clinical studies. Registration: PROSPERO database (CRD42020205213)

Plasma neurological biomarkers as a measure of neurotoxicity in pediatric dental general anesthesia: a prospective observational feasibility study

Purpose: Neurotoxicity concerns have been raised over general anesthesia and sedation medication use in children. Such concerns are largely based on animal studies, historical anesthetic agents, and assessment tools, thus warranting further investigations. Blood biomarkers in detecting neuronal inflammation and apoptosis are novel methods for detecting neuronal damage. Therefore, the aim of this feasibility study was to assess the usefulness of the levels of four plasma biomarkers in dental general anesthesia (DGA) as surrogate markers of neurotoxicity in children. The secondary aim was to compare changes in motor manipulative skills pre- and post-anesthetic exposure. Methods: This single-center prospective observational study included 22 healthy children aged between 3 and 6 years old who underwent DGA. Subclinical neurotoxicity was measured with a panel of four plasma biomarkers: Caspase-3, neuron-specific enolase (NSE), neurofilament light chain, and S100B at three time points (1; at start, 2; end and 3; on recovery from DGA). The Skillings–Mack test was used to identify the difference in the biomarker levels at three time points. Motor manipulative score assessment, prior and two weeks after DGA was also performed. Results: A total of 22 study participants (mean age = 5 ± 1 years) were included with a median DGA duration of 106 ± 28 min. A reduction in Caspase-3 levels was recorded, with pairwise comparison over three time points, reporting a statistical significance between time point 2 vs. 1 and time point 3 vs. 1. Although fluctuations in NSE levels were recorded, no significant changes were found following pairwise comparison analysis. Among other biomarkers, no significant changes over the three periods were recorded. Furthermore, no significant changes in manipulative motor scores were reported. Conclusion: Caspase-3 reduced significantly in the short time frames during day-care DGA; this might be due to the relatively short anesthesia duration associated with dental treatment as compared with more extensive medical-related treatments. Therefore, further studies on Caspase-3 as a potential biomarker in pediatric DGA neurotoxicity are required to further ascertain results of this study.Scopu