A trilogy of tragedies - paediatric dental tooth whitening

Dental tooth whitening is used throughout the United Kingdom for patients who have aesthetic concerns regarding the colour of their teeth. Up until recent months it was also frequently used for paediatric patients with enamel opacities of cosmetic concern and discoloured non-vital anterior teeth. This safe and effective treatment option is now not available to paediatric dental patients due to changes in indemnity cover, and we demonstrate three cases from our department where dental whitening was the most appropriate treatment option. By removing this treatment option for selected paediatric patients, we are concerned that more destructive and less effective treatments may be performed with short- and long-term detriment to their oral health. Furthermore, failure to provide any treatment may negatively affect children's quality of life and psychological well-being

Mapping Extragalactic Dark Matter Annihilation with Galaxy Surveys: A Systematic Study of Stacked Group Searches

Dark matter in the halos surrounding galaxy groups and clusters can annihilate to high-energy photons. Recent advancements in the construction of galaxy group catalogs provide many thousands of potential extragalactic targets for dark matter. In this paper, we outline a procedure to infer the dark matter signal associated with a given galaxy group. Applying this procedure to a catalog of sources, one can create a full-sky map of the brightest extragalactic dark matter targets in the nearby Universe ($z\lesssim 0.03$), supplementing sources of dark matter annihilation from within the Local Group. As with searches for dark matter in dwarf galaxies, these extragalactic targets can be stacked together to enhance the signals associated with dark matter. We validate this procedure on mock $\textit{Fermi}$ gamma-ray data sets using a galaxy catalog constructed from the $\texttt{DarkSky}$ $N$-body cosmological simulation and demonstrate that the limits are robust, at $\mathcal{O}(1)$ levels, to systematic uncertainties on halo mass and concentration. We also quantify other sources of systematic uncertainty arising from the analysis and modeling assumptions. Our results suggest that a stacking analysis using galaxy group catalogs provides a powerful opportunity to discover extragalactic dark matter and complements existing studies of Milky Way dwarf galaxies.Comment: 17+7 pages, 9+4 figures; v2, updated to PRD version with several updates, results and conclusions unchange

In-vivo validity of proximal caries detection in primary teeth, with histological validation.

BACKGROUND: Detection and diagnosis of proximal caries in primary molars is challenging. AIM: The aim of this in-vivo study was to assess the validity and reproducibility of four methods of proximal caries detection in primary molar teeth. DESIGN: Eighty-two children (5-10 yrs) were recruited. Initially 1030 proximal surfaces were examined using meticulous visual examination (ICDAS) (VE1), bitewing radiographs (RE), and a laser fluorescence pen device (LF1). Temporary tooth separation (TTS) was achieved for 447 surfaces and these were re-examined visually (VE2) and using the LF-pen (LF2). Three hundred and fifty-six teeth (542 surfaces) were subsequently extracted and provided histological validation. RESULTS: At D1 (enamel and dentine caries) diagnostic threshold, the sensitivity of VE1, RE, VE2, LF1 and LF2 examination were 0.52, 0.14, 0.75, 0.58, 0.60 and the specificity values were 0.89, 0.97, 0.88, 0.85, 0.77 respectively. At D3 (dentine caries) threshold, the sensitivity values were 0.42, 0.71, 0.49, 0.63, 0.65 respectively, while specificity was 0.93 for VE1 and VE2, and 0.98, 0.87 and 0.88 for RE, LF1 and LF2 examinations respectively. ROC analysis showed radiographic examination to be superior at D3 . CONCLUSION: Meticulous caries diagnosis (ICDAS) should be supported by radiographs for detection of dentinal proximal caries in primary molars

Adolescent valuation of CARIES-QC-U: a child-centred preference-based measure of dental caries

Objectives: This study develops an adolescent value set for a child-centred dental caries-specific measure of oral health-related quality of life (OHRQoL) based upon CARIES-QC (Caries Impacts and Experiences Questionnaire for Children). This study develops a new approach to valuing child health by eliciting adolescent preferences and anchoring these onto the 1-0 full health-dead QALY (quality adjusted life year) scale using ordinal adult preferences.Methods: Two online surveys were created to elicit preferences for the CARIES-QC classification system. The first comprised best-worst scaling (BWS) tasks for completion by adolescents aged 11-16 years. The second comprised discrete choice experiment tasks with a duration attribute (DCETTO) for completion by adults aged over 18 years. Preferences were modelled using the conditional logit model. Mapping regressions anchored the adolescent BWS data onto the QALY scale using adult DCETTO values, since the BWS survey data alone cannot generate anchored values.Results: 723 adolescents completed the BWS survey and 626 adults completed the DCE(TTO )survey. The samples were representative of UK adolescent and adult populations. Fully consistent and robust models were produced for both BWS and DCETTO data. BWS preferences were mapped onto DCETTO values, resulting utility estimates for each health state defined by the classification system.Conclusion: This is the first measure with predetermined scoring based on preferences to be developed specifically for use in child oral health research, and uses a novel technique to generate a value set using adolescent preferences. The estimates can be used to generate QALYs in economic evaluations of interventions to improve children's oral health

Psychosocial impacts relating to dental injuries in childhood: The bigger picture

Traumatic dental injuries (TDI) in childhood are fairly commonplace, with a reported prevalence of up to 30% worldwide. These injuries can have significant impacts on patients, their families and dental professionals; however, this area is currently underrepresented within paediatric oral health research. The psychosocial impacts of traumatic injury are personal to each patient and should be addressed as part of a holistic treatment plan. A review of the current evidence base shows that children who have suffered a traumatic injury to the dentition report worse oral-health-related quality of life. They are also more likely to suffer decreased self-esteem due to their appearance, especially where the injury is not effectively managed. Society (including other children) often judges poorly those with obvious dental disease or anomaly, and with the rising use of social media, these judgements can be made by even greater audiences. There is currently a paucity of qualitative research in this topic to explore the negative psychosocial impacts of dental trauma in greater detail. Although there is growing evidence for the benefit of treatment in improving children’s wellbeing following a TDI, the field of paediatric dental traumatology still has much to learn about young patients’ perspectives, experiences and values

Why Clowns Taste Funny: The Relationship between Humor and Semantic Ambiguity

What makes us laugh? One crucial component of many jokes is the disambiguation of words with multiple meanings. In this functional MRI study of normal participants, the neural mechanisms that underlie our experience of getting a joke that depends on the resolution of semantically ambiguous words were explored. Jokes that contained ambiguous words were compared with sentences that contained ambiguous words but were not funny, as well as to matched verbal jokes that did not depend on semantic ambiguity. The results confirm that both the left inferior temporal gyrus and left inferior frontal gyrus are involved in processing the semantic aspects of language comprehension, while a more widespread network that includes both of these regions and the temporoparietal junction bilaterally is involved in processing humorous verbal jokes when compared with matched nonhumorous material. In addition, hearing jokes was associated with increased activity in a network of subcortical regions, including the amygdala, the ventral striatum, and the midbrain, that have been implicated in experiencing positive reward. Moreover, activity in these regions correlated with the subjective ratings of funniness of the presented material. These results allow a more precise account of how the neural and cognitive processes that are involved in ambiguity resolution contribute to the appreciation of jokes that depend on semantic ambiguity

Dynamics of bead formation, filament thinning and breakup in weakly viscoelastic jets

The spatiotemporal evolution of a viscoelastic jet depends on the relative magnitude of capillary, viscous, inertial and elastic stresses. The interplay of capillary and elastic stresses leads to the formation of very thin and stable filaments between drops, or to ‘beads-on-a-string’ structure. In this paper, we show that by understanding the physical processes that control different stages of the jet evolution it is possible to extract transient extensional viscosity information even for very low viscosity and weakly elastic liquids, which is a particular challenge in using traditional rheometers. The parameter space at which a forced jet can be used as an extensional rheometer is numerically investigated by using a one-dimensional nonlinear free-surface theory for Oldroyd-B and Giesekus fluids. The results show that even when the ratio of viscous to inertio-capillary time scales (or Ohnesorge number) is as low as Oh ~ 0.02, the temporal evolution of the jet can be used to obtain elongational properties of the liquid.Akzo Nobel (Firm

‘I would rather be having my leg cut off than a little needle’: A supplementary qualitative analysis of dentally anxious children’s experiences of needle fear

Fear of needles is common in childhood, with up to 50% being affected to some degree. In individuals who are dentally anxious, the prevalence may be as high as 91%. Fear of needles, and therefore intra-oral injections can have negative impacts on children’s quality of life and healthcare experiences, including a requirement for pharmacological methods to facilitate dental treatment. The aim of this study is to identify whether dentally anxious children report fear of injections and explore how these children experience a fear of needles in a dental setting. A supplementary analysis of interviews collected as part of two previous studies relating to children with dental anxiety. Five main themes were identified: feelings about needles; the nature of needle fear; the context of the fear, its consequences and how children tried to control the process. Children showed a desire to have control of their healthcare interventions, and wanted to trust the healthcare professionals giving the injections. There is evidence that children with dental anxiety also experience fear of needles, including intra-oral injections. Further primary qualitative research is needed to explore this topic in more depth and to design appropriate child centred interventions to reduce needle fear

Patient-reported outcome measure for children and young people with amelogenesis imperfecta

Background: Amelogenesis imperfecta (AI) is a genetic enamel defect that can affect both the primary and permanent dentition. It has a range of clinical phenotypes, and children and young people often present with challenging oral health needs. Patient-reported outcome measures (PROMs) can identify key patient concerns. Methods: This was a multi-centre service evaluation across several specialist paediatric dentistry services in the UK. A PROM questionnaire was created with clinician and patient input, through peer review with the national AI Clinical Excellence Network, as well as piloting the PROM with ten children and young people with AI. The final PROM questionnaire was distributed to all patients with AI attending each unit between January and March 2020. Results: Sixty children and young people (aged 5-17 years) across four specialist units participated, with 72% reporting that they 'often' or 'sometimes' experienced pain or sensitivity and 76% reporting that they 'often' or 'sometimes' felt unhappy with the way their teeth look. Of the patients who were post-treatment, 81% indicated that they were happy with their teeth, compared to just 41% of patients who were mid-treatment and 33% of patients who were pre-treatment. Conclusion: Children and young people with AI experience a range of issues related to their function and psychosocial wellbeing. This simple PROM demonstrates the range of issues this group of patients face, and could be used to monitor an individual's progress to ensure that treatment is planned to address the patient's individual concerns and needs