Prolonged grief during and beyond the pandemic: factors associated with levels of grief in a four time-point longitudinal survey of people bereaved in the first year of the COVID-19 pandemic

Background

The COVID-19 pandemic has been a devastating and enduring mass-bereavement event, with uniquely difficult sets of circumstances experienced by people bereaved at this time. However, little is known about the long-term consequences of these experiences, including the prevalence of Prolonged Grief Disorder (PGD) and other conditions in pandemic-bereaved populations.

Methods

A longitudinal survey of people bereaved in the UK between 16 March 2020 and 2 January 2021, with data collected at baseline (n = 711), c. 8 (n = 383), 13 (n = 295), and 25 (n = 185) months post-bereavement. Using measures of Prolonged Grief Disorder (PGD) (Traumatic Grief Inventory), grief vulnerability (Adult Attitude to Grief Scale), and social support (Inventory of Social Support), this analysis examines how participant characteristics, characteristics of the deceased and pandemic-related circumstances (e.g., restricted visiting, social isolation, social support) are associated with grief outcomes, with a focus on symptoms of PGD.

Results

At baseline, 628 (88.6%) of participants were female, with a mean age of 49.5 (SD 12.9). 311 (43.8%) deaths were from confirmed/suspected COVID-19. Sample demographics were relatively stable across time points. 34.6% of participants met the cut-off for indicated PGD at c. 13 months bereaved and 28.6% at final follow-up. Social isolation and loneliness in early bereavement and lack of social support over time strongly contributed to higher levels of prolonged grief symptoms, while feeling well supported by healthcare professionals following the death was associated with reduced levels of prolonged grief symptoms. Characteristics of the deceased most strongly associated with lower levels of prolonged grief symptoms, were a more distant relationship (e.g., death of a grandparent), an expected death and death occurring in a care-home. Participant characteristics associated with higher levels of prolonged grief symptoms included low level of formal education and existence of medical conditions.

Conclusion

Results suggest higher than expected levels of PGD compared with pre-pandemic times, with important implications for bereavement policy, provision and practice now (e.g., strengthening of social and specialist support) and in preparedness for future pandemics and mass-bereavement events (e.g., guidance on infection control measures and rapid support responses).

Structure-Activity Relationships of Low Molecular Weight Alginate Oligosaccharide Therapy against Pseudomonas aeruginosa

Low molecular weight alginate oligosaccharides have been shown to exhibit anti-microbial activity against a range of multi-drug resistant bacteria, including Pseudomonas aeruginosa. Previous studies suggested that the disruption of calcium (Ca2+)-DNA binding within bacterial biofilms and dysregulation of quorum sensing (QS) were key factors in these observed effects. To further investigate the contribution of Ca2+ binding, G-block (OligoG) and M-block alginate oligosaccharides (OligoM) with comparable average size DPn 19 but contrasting Ca2+ binding properties were prepared. Fourier-transform infrared spectroscopy demonstrated prolonged binding of alginate oligosaccharides to the pseudomonal cell membrane even after hydrodynamic shear treatment. Molecular dynamics simulations and isothermal titration calorimetry revealed that OligoG exhibited stronger interactions with bacterial LPS than OligoM, although this difference was not mirrored by differential reductions in bacterial growth. While confocal laser scanning microscopy showed that both agents demonstrated similar dose-dependent reductions in biofilm formation, OligoG exhibited a stronger QS inhibitory effect and increased potentiation of the antibiotic azithromycin in minimum inhibitory concentration and biofilm assays. This study demonstrates that the anti-microbial effects of alginate oligosaccharides are not purely influenced by Ca2+-dependent processes but also by electrostatic interactions that are common to both G-block and M-block structures.

Survey of practices for documenting evidence of bruises from physical abuse during child protection proceedings

Accurate recording of forensically important information on bruises is vital in child protection proceedings (Royal College of Paediatrics and Child Health (RCPCH)). An online survey was distributed to the RCPCH child protection committees to assess compliance with guidance. 56 individuals were contacted by email, 47 (84%) completed the survey. Results showed that the paediatricians always or usually record size (n=41; 87%), site (n=45; 96%), shape (n=32; 68%) and colour (n=36; 77%); n=10; 22% of the paediatricians stated that they 'always' used a ranking system for likelihood of abuse; n=12; 35% of those surveyed 'sometimes' estimated the size of the bruise. Results showed that paediatric bruise reporting is inconsistent and incomplete for some fields compared with national guidance.

Initial Steps towards a Multilevel Functional Principal Components Analysis Model of Dynamical Shape Changes

In this article, multilevel principal components analysis (mPCA) is used to treat dynamical changes in shape. Results of standard (single-level) PCA are also presented here as a comparison. Monte Carlo (MC) simulation is used to create univariate data (i.e., a single "outcome" variable) that contain two distinct classes of trajectory with time. MC simulation is also used to create multivariate data of sixteen 2D points that (broadly) represent an eye; these data also have two distinct classes of trajectory (an eye blinking and an eye widening in surprise). This is followed by an application of mPCA and single-level PCA to "real" data consisting of twelve 3D landmarks outlining the mouth that are tracked over all phases of a smile. By consideration of eigenvalues, results for the MC datasets find correctly that variation due to differences in groups between the two classes of trajectories are larger than variation within each group. In both cases, differences in standardized component scores between the two groups are observed as expected. Modes of variation are shown to model the univariate MC data correctly, and good model fits are found for both the "blinking" and "surprised" trajectories for the MC "eye" data. Results for the "smile" data show that the smile trajectory is modelled correctly; that is, the corners of the mouth are drawn backwards and wider during a smile. Furthermore, the first mode of variation at level 1 of the mPCA model shows only subtle and minor changes in mouth shape due to sex; whereas the first mode of variation at level 2 of the mPCA model governs whether the mouth is upturned or downturned. These results are all an excellent test of mPCA, showing that mPCA presents a viable method of modeling dynamical changes in shape.

Factors Associated With Higher Levels of Grief and Support Needs Among People Bereaved During the Pandemic: Results from a National Online Survey

We identified factors associated with higher levels of grief and support needs among 711 people bereaved during the COVID-19 pandemic in the UK (deaths 16 March 2020-2 January 2021). An online survey assessed grief using the Adult Attitude to Grief (AAG) scale, which calculates an overall index of vulnerability (IOV) (range 0-36), and practical and emotional support needs in 13 domains. Participants' mean age was 49.5 (SD 12.9); 628 (88.6%) female. Mean age of deceased 72.2 (SD 16.1). 311 (43.8%) deaths were from confirmed/suspected COVID-19. High overall levels of grief and support needs were observed; 28.2% exhibited severe vulnerability (index of vulnerability ≥24). Grief and support needs were higher for close relationships with the deceased (vs. more distant) and reported social isolation and loneliness (p < 0.001), and lower when age of deceased was above 40-50. Other associated factors were place of death and health professional support post-death (p < 0.05).

'It was brutal. It still is': a qualitative analysis of the challenges of bereavement during the COVID-19 pandemic reported in two national surveys

Background:

The COVID-19 pandemic has been a devastating, mass bereavement event characterised by high levels of disruption to end-of-life, grieving and coping processes. Quantitative evidence is emerging on the effects of the pandemic on grief outcomes, but rich qualitative evidence on the lived experiences of people bereaved during these times is lacking.

Methods:

We analysed qualitative data from two independent UK-wide online surveys to describe the experiences of 881 people bereaved during the pandemic. We analysed the data in two phases, conducting an inductive thematic analysis and then applying Stroebe and Schut’s Dual Process Model (DPM) and concepts of loss-oriented and restoration-oriented coping (1999; 2010) as an analytic lens to further contextualise and interpret the data.

Results:

We identified six main themes: troubled deaths; mourning, memorialisation and death administration; mass bereavement, the media and the ongoing threat of the pandemic; grieving and coping; work and employment; and support from the health and social care system. Examples of loss-oriented stressors included being unable to visit and say goodbye at the end of life and restricted funeral and memorialisation practices. Associated reactions were feelings of guilt, anger, and problems accepting the death and beginning to grieve. Examples of restoration-oriented stressors and reactions were severely curtailed support-systems and social/recreational activities, which impacted people’s ability to cope.

Conclusion:

Study results demonstrate the exceptionally difficult sets of experiences associated with pandemic bereavement, and the utility of the DPM for conceptualising these additional challenges and their impacts on grieving. Our analysis builds and expands on previous use of the DPM in explicating the impact of the pandemic on bereavement. We make recommendations for statutory, private and third sector organisations for improving the experiences of people bereaved during and following this and future pandemics.

An Exploration of Pathologies of Multilevel Principal Components Analysis in Statistical Models of Shape

3D facial surface imaging is a useful tool in dentistry and in terms of diagnostics and treatment planning. Between-group PCA (bgPCA) is a method that has been used to analyse shapes in biological morphometrics, although various “pathologies” of bgPCA have recently been proposed. Monte Carlo (MC) simulated datasets were created here in order to explore “pathologies” of multilevel PCA (mPCA), where mPCA with two levels is equivalent to bgPCA. The first set of MC experiments involved 300 uncorrelated normally distributed variables, whereas the second set of MC experiments used correlated multivariate MC data describing 3D facial shape. We confirmed results of numerical experiments from other researchers that indicated that bgPCA (and so also mPCA) can give a false impression of strong differences in component scores between groups when there is none in reality. These spurious differences in component scores via mPCA decreased significantly as the sample sizes per group were increased. Eigenvalues via mPCA were also found to be strongly affected by imbalances in sample sizes per group, although this problem was removed by using weighted forms of covariance matrices suggested by the maximum likelihood solution of the two-level model. However, this did not solve problems of spurious differences between groups in these simulations, which was driven by very small sample sizes in one group. As a “rule of thumb” only, all of our experiments indicate that reasonable results are obtained when sample sizes per group in all groups are at least equal to the number of variables. Interestingly, the sum of all eigenvalues over both levels via mPCA scaled approximately linearly with the inverse of the sample size per group in all experiments. Finally, between-group variation was added explicitly to the MC data generation model in two experiments considered here. Results for the sum of all eigenvalues via mPCA predicted the asymptotic amount for the total amount of variance correctly in this case, whereas standard “single-level” PCA underestimated this quantity.

Influence of remaining axial walls on of root filled teeth restored with a single crown and adhesively bonded fibre post: A systematic review and meta-analysis

OBJECTIVES

To synthesise evidence on structural failures and prevalence of post-treatment endodontic disease (PTD) in anterior and posterior root filled teeth with a single crown and adhesively bonded fibre post with regards to the number of axial walls.

DATA

An electronic search was performed, no language constraints or restriction on the year of publication were applied.

SOURCES

PubMed, Medline, Cochrane and Scopus on 13th of July 2021.

STUDY SELECTION

Clinical studies that reported the remaining number of axial walls for permanent anterior and posterior root filled teeth (RFT) restored with single crowns and adhesively bonded fibre posts with a minimum of 1 year follow-up were included. Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines [1] were used. The number of axial walls and the success/failures were analysed as follows: fibre post and/or core decementation, post and/or core fracture and post treatment endodontic disease, and root fracture.

CONCLUSIONS

A total of 811 studies were identified with 5 meeting the inclusion criteria. The two randomized controlled trials included had 'some concerns' as determined by the Cochrane risk-of-bias 2 tool while the Newcastle-Ottawa scale found low risk of bias for the remaining three studies. The random effects model for subgroup meta-analysis revealed failures for posterior RFT increased with decreasing numbers of remaining walls. Failures for 0 remaining walls were 23% (95% CI = 10% - 36%) and for one remaining wall 15% (CI: 3% -26%), irrespective of follow-up times. Fibre post debonding and PTD increased with decreasing numbers of walls. Relative & catastrophic failure of posterior teeth restored with a fibre post and single crown after root canal treatment increased with decreasing numbers of remaining axial walls.

CLINICAL SIGNIFICANCE

This synthesis is unique as it minimizes the presence of confounding factors by reviewing evidence of failures and post-treatment endodontic disease associated with teeth restored with single crowns. Therefore, it provides valuable predictive evidence of potential coronal restoration catastrophes and post-treatment endodontic disease associated with root filled teeth.

An exploration of adolescent facial shape changes with age via multilevel partial least squares regression

BACKGROUND AND OBJECTIVES

Multilevel statistical models represent the existence of hierarchies or clustering within populations of subjects (or shapes in this work). This is a distinct advantage over single-level methods that do not. Multilevel partial-least squares regression (mPLSR) is used here to study facial shape changes with age during adolescence in Welsh and Finnish samples comprising males and females.

METHODS

3D facial images were obtained for Welsh and Finnish male and female subjects at multiple ages from 12 to 17 years old. 1000 3D points were defined regularly for each shape by using "meshmonk" software. A three-level model was used here, including level 1 (sex/ethnicity); level 2, all "subject" variations excluding sex, ethnicity, and age; and level 3, age. The mathematical formalism of mPLSR is given in an Appendix.

RESULTS

Differences in facial shape between the ages of 12 and 17 predicted by mPLSR agree well with previous results of multilevel principal components analysis (mPCA); buccal fat is reduced with increasing age and features such as the nose, brow, and chin become larger and more distinct. Differences due to ethnicity and sex are also observed. Plausible simulated faces are predicted from the model for different ages, sexes and ethnicities. Our models provide good representations of the shape data by consideration of appropriate measures of model fit (RMSE and R2).

CONCLUSIONS

Repeat measures in our dataset for the same subject at different ages can only be modelled indirectly at the lowest level of the model at discrete ages via mPCA. By contrast, mPLSR models age explicitly as a continuous covariate, which is a strong advantage of mPLSR over mPCA. These investigations demonstrate that multivariate multilevel methods such as mPLSR can be used to describe such age-related changes for dense 3D point data. mPLSR might be of much use in future for the prediction of facial shapes for missing persons at specific ages or for simulating shapes for syndromes that affect facial shape in new subject populations.

Factors associated with dental fluorosis among Malaysian children exposed to different fluoride concentrations in the public water supply

OBJECTIVES

To determine the prevalence of dental fluorosis, and factors associated with its occurrence in two cohorts of children exposed to different fluoride concentrations in the Malaysian water supply.

METHODS

A cross-sectional study was conducted among lifelong residents (n = 1,155) aged 9 and 12 years old living in fluoridated and nonfluoridated areas. Malaysian children aged 12 years were born when the level of fluoride in the public water supply was 0.7 ppm while those aged 9 years were born after the level was reduced to 0.5 ppm. Fluorosis was blind scored using standardized photographs of maxillary central incisors using Dean's criteria. Fluoride exposures and other factors were assessed by parental questionnaire. Data were analyzed using descriptive statistics, Chi-squared analyses, and logistic regression.

RESULTS

Fluorosis prevalence was lower (31.9 percent) among the younger children born after the reduction of fluoride concentration in the water, compared to a prevalence of 38.4 percent in the older cohort. Early tooth brushing practices and fluoridated toothpaste were not statistically associated with fluorosis status. However, the prevalence of fluorosis was significantly associated with parents' education level, parents' income, fluoridated water, type of infant feeding method, age breast feeding ceased, use of formula milk, duration of formula milk intake, and type of water used to reconstitute formula milk via simple logistic regression. Fluoridated water remained a significant risk factor for fluorosis in multiple logistic regression.

CONCLUSIONS

Fluorosis was lower among children born after the adjustment of fluoride concentration in the water. Fluoridated water remained as a strong risk factor for fluorosis after downward adjustment of its fluoride concentration.

Initial Investigations of the Cranial Size and Shape of Adult Eurasian Otters (Lutra lutra) in Great Britain

Three-dimensional (3D) surface scans were carried out in order to determine the shapes of the upper sections of (skeletal) crania of adult Eurasian otters (Lutra lutra) from Great Britain. Landmark points were placed on these shapes using a graphical user interface (GUI) and distance measurements (i.e., the length, height, and width of the crania) were found by using the landmark points. Male otters had significantly larger skulls than females (P < 0.001). Differences in size also occurred by geographical area in Great Britain (P < 0.05). Multilevel Principal Components Analysis (mPCA) indicated that sex and geographical area explained 31.1% and 9.6% of shape variation in "unscaled" shape data and that they explained 17.2% and 9.7% of variation in "scaled" data. The first mode of variation at level 1 (sex) correctly reflected size changes between males and females for "unscaled" shape data. Modes at level 2 (geographical area) also showed possible changes in size and shape. Clustering by sex and geographical area was observed in standardized component scores. Such clustering in a cranial shape by geographical area might reflect genetic differences in otter populations in Great Britain, although other potentially confounding factors (e.g., population age-structure, diet, etc.) might also drive regional differences. This work provides a successful first test of the effectiveness of 3D surface scans and multivariate methods, such as mPCA, to study the cranial morphology of otters.

Multilevel principal components analysis of three-dimensional facial growth in adolescents

BACKGROUND AND OBJECTIVES

The study of age-related facial shape changes across different populations and sexes requires new multivariate tools to disentangle different sources of variations present in 3D facial images. Here we wish to use a multivariate technique called multilevel principal components analysis (mPCA) to study three-dimensional facial growth in adolescents.

METHODS

These facial shapes were captured for Welsh and Finnish subjects (both male and female) at multiple ages from 12 to 17 years old (i.e., repeated-measures data). 1000 "dense" 3D points were defined regularly for each shape by using a deformable template via "meshmonk" software. A three-level model was used here, namely: level 1 (sex/ethnicity); level 2, all "subject" variations excluding sex, ethnicity, and age; and level 3, age. The technicalities underpinning the mPCA method are presented in Appendices.

RESULTS

Eigenvalues via mPCA predicted that: level 1 (ethnicity/sex) contained 7.9% of variation; level 2 contained 71.5%; and level 3 (age) contained 20.6%. The results for the eigenvalues via mPCA followed a similar pattern to those results of single-level PCA. Results for modes of variation made sense, where effects due to ethnicity, sex, and age were reflected in modes at appropriate levels of the model. Standardised scores at level 1 via mPCA showed much stronger differentiation between sex and ethnicity groups than results of single-level PCA. Results for standardised scores from both single-level PCA and mPCA at level 3 indicated that females had different average "trajectories" with respect to these scores than males, which suggests that facial shape matures in different ways for males and females. No strong evidence of differences in growth patterns between Finnish and Welsh subjects was observed.

CONCLUSIONS

mPCA results agree with existing research relating to the general process of facial changes in adolescents with respect to age quoted in the literature. They support previous evidence that suggests that males demonstrate larger changes and for a longer period of time compared to females, especially in the lower third of the face. These calculations are therefore an excellent initial test that multivariate multilevel methods such as mPCA can be used to describe such age-related changes for "dense" 3D point data.

The ALERT-B questionnaire: A screening tool for the detection of gastroenterological late effects after radiotherapy for prostate cancer

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ALERT-B provides an effective screening tool for gastroenterological late effects.

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84.4% and 95.7% of patients demonstrated complications at 6 and 12 months post-treatment.

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ROC curves at baseline indicated an AUC of 0.867 compared to the GSRS diarrhoea subscale.

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ROC curves at baseline indicated an AUC of 0.765 compared to the EPIC bowel subscale.

There is an increasing need to measure treatment-related side effects in normal tissues following cancer therapy. The ALERT-B (Assessment of Late Effects of RadioTherapy - Bowel) questionnaire is a screening tool that is composed of four items related specifically to bowel symptoms. Those patients that respond with a “yes” to any of these items are referred on to gastroenterologist in order to improve the long-term consequences of these side effects of radiological treatment. Here we wish to test the ability of this questionnaire to identify these subsequent gastroenterological complications by tracking prostate cancer patients that were positive with respect to ALERT-B. We also carry out receiver-operator curve (ROC) analysis for baseline data for an overall ALERT-B questionnaire score with respect to subscale data for the Gastrointestinal Symptom Rating Scale (GSRS) and the Expanded Prostate Cancer Index Composite (EPIC-26) questionnaire. 84.4% and 95.7% of patients identified by the ALERT-B questionnaire demonstrated complications diagnosed at 6 and 12 months post-treatment, respectively. ROC curve analysis of baseline data showed that ALERT-B detected clinically relevant levels of side effects established at baseline by the GSRS diarrhoea subscale (AUC = 0.867, 95% CI = 0.795 to 0.926) and at the minimally important level of side effects for the EPIC bowel subscale (AUC = 0.765, 95% CI = 0.617 to 0.913). These results show that ALERT-B provides a simple and effective screening tool for identifying gastroenterological complications after treatment for prostate cancer.

Cellulose Nanofibril Formulations Incorporating a Low-Molecular-Weight Alginate Oligosaccharide Modify Bacterial Biofilm Development

Cellulose nanofibrils (CNFs) from wood pulp are a renewable material possessing advantages for biomedical applications because of their customizable porosity, mechanical strength, translucency, and environmental biodegradability. Here, we investigated the growth of multispecies wound biofilms on CNF formulated as aerogels and films incorporating the low-molecular-weight alginate oligosaccharide OligoG CF-5/20 to evaluate their structural and antimicrobial properties. Overnight microbial cultures were adjusted to 2.8 × 10⁹ colony-forming units (cfu) mL^-1 in Mueller Hinton broth and growth rates of Pseudomonas aeruginosa PAO1 and Staphylococcus aureus 1061A monitored for 24 h in CNF dispersions sterilized by γ-irradiation. Two CNF formulations were prepared (20 g m^-2) with CNF as air-dried films or freeze-dried aerogels, with or without incorporation of an antimicrobial alginate oligosaccharide (OligoG CF-5/20) as a surface coating or bionanocomposite, respectively. The materials were structurally characterized by scanning electron microscopy (SEM) and laser profilometry (LP). The antimicrobial properties of the formulations were assessed using single- and mixed-species biofilms grown on the materials and analyzed using LIVE/DEAD staining with confocal laser scanning microscopy (CLSM) and COMSTAT software. OligoG-CNF suspensions significantly decreased the growth of both bacterial strains at OligoG concentrations >2.58% (P < 0.05). SEM showed that aerogel-OligoG bionanocomposite formulations had a more open three-dimensional structure, whereas LP showed that film formulations coated with OligoG were significantly smoother than untreated films or films incorporating PEG400 as a plasticizer (P < 0.05). CLSM of biofilms grown on films incorporating OligoG demonstrated altered biofilm architecture, with reduced biomass and decreased cell viability. The OligoG-CNF formulations as aerogels or films both inhibited pyocyanin production (P < 0.05). These novel CNF formulations or bionanocomposites were able to modify bacterial growth, biofilm development, and virulence factor production in vitro. These data support the potential of OligoG and CNF bionanocomposites for use in biomedical applications where prevention of infection or biofilm growth is required.

What's in a Smile? Initial Analyses of Dynamic Changes in Facial Shape and Appearance

Single-level principal component analysis (PCA) and multi-level PCA (mPCA) methods are applied here to a set of (2D frontal) facial images from a group of 80 Finnish subjects (34 male; 46 female) with two different facial expressions (smiling and neutral) per subject. Inspection of eigenvalues gives insight into the importance of different factors affecting shapes, including: biological sex, facial expression (neutral versus smiling), and all other variations. Biological sex and facial expression are shown to be reflected in those components at appropriate levels of the mPCA model. Dynamic 3D shape data for all phases of a smile made up a second dataset sampled from 60 adult British subjects (31 male; 29 female). Modes of variation reflected the act of smiling at the correct level of the mPCA model. Seven phases of the dynamic smiles are identified: rest pre-smile, onset 1 (acceleration), onset 2 (deceleration), apex, offset 1 (acceleration), offset 2 (deceleration), and rest post-smile. A clear cycle is observed in standardized scores at an appropriate level for mPCA and in single-level PCA. mPCA can be used to study static shapes and images, as well as dynamic changes in shape. It gave us much insight into the question “what’s in a smile?”.

Management of orthodontic emergencies in primary care - self-reported confidence of general dental practitioners

Objective To determine general dental practitioners' (GDPs) confidence in managing orthodontic emergencies.Design Cross-sectional study.Setting Primary dental care.Subjects and methods An online survey was distributed to dentists practicing in Wales. The survey collected basic demographic information and included descriptions of ten common orthodontic emergency scenarios.Main outcome measure Respondents' self-reported confidence in managing the orthodontic emergency scenarios on a 5-point Likert scale. Differences between the Likert responses and the demographic variables were investigated using chi-squared tests.Results The median number of orthodontic emergencies encountered by respondents over the previous six months was 1. Overall, the self-reported confidence of respondents was high with 7 of the 10 scenarios presented scoring a median of 4 indicating that GDPs were 'confident' in their management. Statistical analysis revealed that GDPs who saw more orthodontic emergencies in the previous six months were more confident when managing the presented scenarios. Other variables such as age, gender, geographic location of practice and number of years practising dentistry were not associated with self-reported confidence.Conclusions Despite GDPs encountering very few orthodontic emergencies in primary care, they appear to be confident in dealing with commonly arising orthodontic emergency situations.

Antibiotic prescribing for endodontic therapies: a comparative survey between general dental practitioners and final year Bachelor of Dental Surgery students in Cardiff, UK

AIM

To evaluate the views of final year dental surgery students (BDS; G1) at Cardiff University and general dental practitioners (GDPs; G2) within the geographic area of Cardiff, Wales, on antibiotic prescribing for endodontic conditions, and investigate the potential differences between the two groups.

METHODS

A cross-sectional online questionnaire-based survey of 12 qualitative and quantitative questions was distributed to 76 final year BDS Cardiff University students and 55 dental practices within Cardiff, UK. Six questions recorded general information, and the remaining questions included a series of hypothetical clinical scenarios, where the participants were asked to state whether they would or would not prescribe antibiotics. The data were analysed using spss version 23 to produce descriptive statistics, contingency tables and to run chi-square (χ²) tests, Fisher's exact tests and relative risk calculations.

RESULTS

The response rate was 60% (n = 79). All G1 participants were aware of the consequences of antibiotic overuse. Approximately 60% of responders were aware of guidelines for antibiotic use in endodontic therapies, and 83% would only use antibiotics for a limited selection of patients (e.g. patients with systemic complications). G1 responses to clinical scenarios indicated overall that they were comparable to the ideal answers except for acute apical abscess (64% believed that antibiotics were indicated). The majority of G2 were aware of the consequences of antibiotic overuse. Only 28% of G2 were aware of guidelines for antibiotic use in endodontic therapies. Overall responses revealed that antibiotics would be prescribed for: systemic complications (78%), acute apical abscess (72%) and symptomatic apical periodontitis (28%). The clinical scenarios revealed G1 were more likely to prescribe antibiotics compared to G2 for cases of necrotic pulp with symptomatic apical periodontitis without systemic complications (incorrect answer) and less likely to other clinical scenarios such as necrotic pulp and asymptomatic apical periodontitis for patients with a history of rheumatic fever (ideal answers), symptomatic irreversible/reversible pulpitis, failure to achieve anaesthesia, chronic apical abscess for patients with diabetes. The recognition of antibiotic prescription for cases with signs of spreading infection was more evident in G2.

CONCLUSION

Final year undergraduate students were aware of the antibiotic resistance crisis, although a third was not aware of guidelines for use of antibiotics in endodontic conditions; their responses to clinical scenario were generally compatible with the guidelines. General dentists were less aware of the implications of overuse of antibiotics and the existence of guidelines, and their responses were occasionally incompatible with antibiotic guidelines for endodontic therapies.

A Systematic Review of Information Literacy Programs in Higher Education: Effects of Face-to-Face, Online, and Blended Formats on Student Skills and Views

Abstract Objective – Evidence from systematic reviews a decade ago suggested that face-to-face and online methods to provide information literacy training in universities were equally effective in terms of skills learnt, but there was a lack of robust comparative research. The objectives of this review were (1) to update these findings with the inclusion of more recent primary research; (2) to further enhance the summary of existing evidence by including studies of blended formats (with components of both online and face-to-face teaching) compared to single format education; and (3) to explore student views on the various formats employed. Methods – Authors searched seven databases along with a range of supplementary search methods to identify comparative research studies, dated January 1995 to October 2016, exploring skill outcomes for students enrolled in higher education programs. There were 33 studies included, of which 19 also contained comparative data on student views. Where feasible, meta-analyses were carried out to provide summary estimates of skills development and a thematic analysis was completed to identify student views across the different formats. Results – A large majority of studies (27 of 33; 82%) found no statistically significant difference between formats in skills outcomes for students. Of 13 studies that could be included in a meta-analysis, the standardized mean difference (SMD) between skill test results for face-to-face versus online formats was -0.01 (95% confidence interval -0.28 to 0.26). Of ten studies comparing blended to single delivery format, seven (70%) found no statistically significant difference between formats, and the remaining studies had mixed outcomes. From the limited evidence available across all studies, there is a potential dichotomy between outcomes measured via skill test and assignment (course work) which is worthy of further investigation. The thematic analysis of student views found no preference in relation to format on a range of measures in 14 of 19 studies (74%). The remainder identified that students perceived advantages and disadvantages for each format but had no overall preference. Conclusions – There is compelling evidence that information literacy training is effective and well received across a range of delivery formats. Further research looking at blended versus single format methods, and the time implications for each, as well as comparing assignment to skill test outcomes would be valuable. Future studies should adopt a methodologically robust design (such as the randomized controlled trial) with a large student population and validated outcome measures.

A Comparative Study of ProTaper Universal and ProTaper Next Used by Undergraduate Students to Prepare Root Canals

INTRODUCTION

The purpose of this study was to determine whether final-year undergraduate dental students achieved better shaping outcomes using the new ProTaper Next (PTN; Dentsply Sirona, Ballaigues, Switzerland) system to prepare root canals for the first time compared with the existing ProTaper Universal (PTU, Dentsply Sirona) system on which they had trained. A secondary aim was to explore the attitudes and preferences of the students toward both systems.

METHODS

Forty students prepared 1 simulated S-shaped canal using PTN and another with PTU. Images of the canals were saved before and after preparation, and the outcomes assessed included the formation of aberrations and the amount of resin removed at specific points along the canal length. Student opinions relating to PTN and PTU were collected via a questionnaire completed immediately after using the systems. For statistical analysis, the McNemar test was used to compare the incidence of aberrations, and a paired t test was used to analyze the width measurements. Responses to the questionnaire were analyzed using frequencies. Thus, the McNemar test was used for paired binary data and the marginal homogeneity test for categoric data when more than 2 categories were used. Finally, the overall preferences (either PTN or PTU) were analyzed using the sign/binomial test, which is a standard statistical test that allows us to determine if the proportion preferring one or the other is equal or not.

RESULTS

Canal ledges were formed in 30% of the canals prepared with PTU, whereas no ledges were formed with PTN (P < .001). A middle constriction, a form of canal aberration, was created by both systems although it occurred significantly (P = .006) more often with PTN. The "number of files" was judged by students to be significantly higher (P < .001) for PTU compared with PTN. Even though using PTN for the first time, students were more likely to recommend the system to other students for preparing S-shaped canals than PTU (P = .018) and preferred to use PTN in the future (P < .001).

CONCLUSIONS

The students who had previous experience with the use of PTU were able to produce comparable shaping outcomes when they used PTN for the first time. For the preparation of S-shaped canals, the students preferred PTN over PTU in terms of the number of files and would prefer to use it in the future.

Improving the well-being of men by Evaluating and Addressing the Gastrointestinal Late Effects (EAGLE) of radical treatment for prostate cancer: study protocol for a mixed-method implementation project

INTRODUCTION

Radiotherapy treatment for prostate cancer can cause bowel problems, which may lead to severe difficulties for cancer survivors including limiting travel, work or socialising. These symptoms can appear at any time following radiotherapy. This study focuses on the early identification and protocol-based management of effects known to cause long-term, or even permanent, changes to the well-being of prostate cancer survivors. The rationale of this study is to improve the care offered to men and their families following pelvic radiotherapy for prostate cancer.

METHOD AND ANALYSIS

Implementation research methodology will be used to adopt a multicomponent intervention at three UK centres. The intervention package comprises a standardised clinical assessment of relevant symptoms in oncology outpatient clinics and rapid referral to an enhanced gastroenterological service for patients identified with bowel problems. Gastroenterology staff will be trained to use an expert-practice algorithm of targeted gastroenterology investigations and treatments. The evaluation of the intervention and its embedding within local practices will be conducted using a mixed-methods design. The effect of the new service will be measured in terms of the following outcomes: acceptability to staff and patients; quality of life; symptom control and cost-effectiveness. Data collection will take place at baseline, 6 months (±2 months), and 12 months (±2 months) after entry into the study.

ETHICS AND DISSEMINATION

The study has ethical approval from the North West-Liverpool East Research Ethics Committee and the appropriate NHS governance clearance. All participants provide written informed consent. The study team aim to publish the results of the study in peer-reviewed journals as well as at national and international conferences.

TRIAL REGISTRATION NUMBER

UKCRN16974.

Multilevel principal component analysis (mPCA) in shape analysis: A feasibility study in medical and dental imaging

BACKGROUND AND OBJECTIVE

Methods used in image processing should reflect any multilevel structures inherent in the image dataset or they run the risk of functioning inadequately. We wish to test the feasibility of multilevel principal components analysis (PCA) to build active shape models (ASMs) for cases relevant to medical and dental imaging.

METHODS

Multilevel PCA was used to carry out model fitting to sets of landmark points and it was compared to the results of "standard" (single-level) PCA. Proof of principle was tested by applying mPCA to model basic peri-oral expressions (happy, neutral, sad) approximated to the junction between the mouth/lips. Monte Carlo simulations were used to create this data which allowed exploration of practical implementation issues such as the number of landmark points, number of images, and number of groups (i.e., "expressions" for this example). To further test the robustness of the method, mPCA was subsequently applied to a dental imaging dataset utilising landmark points (placed by different clinicians) along the boundary of mandibular cortical bone in panoramic radiographs of the face.

RESULTS

Changes of expression that varied between groups were modelled correctly at one level of the model and changes in lip width that varied within groups at another for the Monte Carlo dataset. Extreme cases in the test dataset were modelled adequately by mPCA but not by standard PCA. Similarly, variations in the shape of the cortical bone were modelled by one level of mPCA and variations between the experts at another for the panoramic radiographs dataset. Results for mPCA were found to be comparable to those of standard PCA for point-to-point errors via miss-one-out testing for this dataset. These errors reduce with increasing number of eigenvectors/values retained, as expected.

CONCLUSIONS

We have shown that mPCA can be used in shape models for dental and medical image processing. mPCA was found to provide more control and flexibility when compared to standard "single-level" PCA. Specifically, mPCA is preferable to "standard" PCA when multiple levels occur naturally in the dataset.

Effectiveness of an audience response system on orthodontic knowledge retention of undergraduate dental students--a randomised control trial

Objective:: To determine the effect of an audience response system (ARS) on knowledge retention of dental students and to gauge student perceptions of using the ARS. Design:: Randomised control study. Setting:: School of Dentistry, Cardiff University. Participants:: Seventy four second-year dental students were stratified by gender and randomised anonymously to one of two groups. Methods:: One group received a lecture on orthodontic terminology and diagnosis in a traditional didactic format and the other received the same lecture integrated with ARS slides. Students completed an assessment of multiple-choice questions (MCQs) scored out of 20, before and immediately after the lecture. Students were also asked to complete a self-reported questionnaire on their perceptions of ARS. Results:: Both groups had statistically significant increases in MCQ scores post-lecture (ARS mean increase 3.6 SD2.0, 95% CI 2.2–3.5 and Didactic mean increase 2.9 SD2.3, 95% CI 2.8–4.3). A mixed-design analysis of variance showed that ARS led to an improved MCQ score (by 0.8 or 25%) compared to the didactic group, although this effect was not significant (P = 0.15). The effect of gender at baseline (P = 0.49), post-lecture (P = 0.73) and increase in MCQ score split by group (P = 0.46) was also not significant. Students reported that the ARS was easy to use, helped them engage with the lecture and encouraged them to work harder. Conclusion:: The ARS did not lead to a significant increase in short-term orthodontic knowledge recall of students compared with didactic teaching. However, the use of ARS within orthodontic teaching could make lectures more interactive and engaging.

The frustrated Heisenberg antiferromagnet on the honeycomb lattice: J1-J2 model

We study the ground-state phase diagram of the frustrated spin-[Formula: see text] antiferromagnet with J(2) = xJ(1) > 0 (J(1) > 0) on the honeycomb lattice, using the coupled-cluster method. We present results for the ground-state energy, magnetic order parameter and plaquette valence-bond crystal (PVBC) susceptibility. We find a paramagnetic PVBC phase for x(c(1)) < x < x(c(2)), where x(c(1)) ≈ 0.207 ± 0.003 and x(c(2)) ≈ 0.385 ± 0.010. The transition at x(c(1)) to the Néel phase seems to be a continuous deconfined transition (although we cannot exclude a very narrow intermediate phase in the range 0.21 ≲ x ≲ 0.24), while that at x(c(2)) is of first-order type to another quasiclassical antiferromagnetic phase that occurs in the classical version of the model only at the isolated and highly degenerate critical point [Formula: see text]. The spiral phases that are present classically for all values x > 1/6 are absent for all x ≲ 1.

Prospective analysis of patient-reported late toxicity following pelvic radiotherapy for gynaecological cancer

BACKGROUND AND PURPOSE

As late radiotherapy toxicity impacts negatively on the quality-of-life of cancer survivors and is often under reported, a study was set up to prospectively collect patient-reported data in an unselected series of patients with gynaecological malignancy. Aim 1 - To provide 3 year results for the longitudinal study. Aim 2 - To improve the questionnaire used to collect data by identifying redundant items and modifying for use to collect Common Terminology Criteria for Adverse Events (CTCAE) data.

MATERIAL AND METHODS

Aim 1 - Patient reported outcome data were collected prospectively by 226 patients before and up to 3 years following radiotherapy for gynaecological cancer using a questionnaire developed to collect LENT subjective data. Aim 2 - A factor analysis was performed to identify which questions gave the most and least information.

RESULTS

Aim 1 - Faecal urgency and incontinence (all grades) peaked at 79% and 24%, respectively at 1 year then settled to 69% and 18% at 3 years, respectively. Urinary urgency (all grades) increased with time and was described in 75% at 3 years. Other symptoms reported at 3 years include diarrhoea in 12%, urinary incontinence in 27% and vaginal dryness in 29%. A third of patients did not feel their sex life had changed following treatment, while a quarter felt that it had. Aim 2 - some questions overlapped and others were non-specific. The questionnaire has subsequently been altered.

CONCLUSIONS

The extent of late toxicity is substantial. This detailed information is important for both patients and clinicians in terms of treatment decisions and follow-up care. The LENT questionnaire provides a feasible tool for capture of this information in the clinic.

Measurement error in statistical models of shape

Active shape models (ASMs) are popular and sophisticated methods of extracting features in (especially medical) images. Here we analyse the error in placing ASM points on the boundary of the feature. By using replications, a corrected covariance matrix is presented that should reduce the effects of placement error. We show analytically and via simulations that the cumulative variability for a given number of eigenvalues retained in principal components analysis (PCA) ought to be reduced by increasing levels of point-placement error. Results for predicted errors are in excellent agreement with the set-up parameters of two simulated shapes and with anecdotal evidence from the trained experts for real data taken from the OSTEODENT project. We derive an equation for the reliability of placing the points and we find values of 0.79 and 0.85 (where 0=bad and 1=good) for the two clinical experts for the OSTEODENT data. These analyses help us to understand the sources and effects of measurement error in shape models.

Perception of tilt following counter-rotation surgery

BACKGROUND

Macular translocation surgery (MTS) is one of the treatment options for age-related macular degeneration (AMD) followed by counter-rotation surgery (CRS) to correct the resulting tilt. The objective of this paper is to determine the perception of tilt following CRS and identify factors that influence the perception of tilt in the presence of residual cyclorotation following CRS.

METHODS

Thirty-four AMD patients treated with MTS and CRS were investigated; and all measurements were made preoperatively, and after each surgical procedure. Fundus photographs were analysed with computer software to determine the degree of retinal rotation and reliability was assessed by two independent assessors. The degree of perceptual rotation was measured with Maddox rod and the subjective appreciation of tilt was established by direct questioning. Fixation preference was determined by cover test and convergence. Bagolini glasses were used to determine binocular outcome.

RESULTS

Post CRS, 20 of the 34 patients had adapted to tilt. There was a significant difference of 5 degrees +/- 7 degrees (95% confidence intervals: 1-8 degrees , t = 2.9, degree of freedom = 19, P = 0.008) between the degree of rotation measured from the fundus photographs and the Maddox rod measurement following CRS. Patients with residual retinal rotation less than or equal to 15 degrees did not appreciate tilt in free space. More importantly, fixation with the operated eye and ignoring the image from the non-operated eye was significantly associated with being free of tilt in natural viewing conditions (P < 0.05).

CONCLUSION

Despite the presence of residual cyclorotation of the macula following CRS of up to 27 degrees , a significant proportion (59%) of patients did not perceive the world as tilted in natural viewing conditions. Differences between retinal rotation and perceptual tilt provide evidence of sensory adaptation. It was patients who fixed with their operated eye and ignored the image from the non-operated eye who did not perceive tilt post CRS.

High-order coupled cluster method study of frustrated and unfrustrated quantum magnets in external magnetic fields

We apply the coupled cluster method (CCM) in order to study the ground-state properties of the (unfrustrated) square-lattice and (frustrated) triangular-lattice spin-half Heisenberg antiferromagnets in the presence of external magnetic fields. Approximate methods are difficult to apply to the triangular-lattice antiferromagnet because of frustration, and so, for example, the quantum Monte Carlo (QMC) method suffers from the 'sign problem'. Results for this model in the presence of magnetic field are rarer than those for the square-lattice system. Here we determine and solve the basic CCM equations by using the localized approximation scheme commonly referred to as the 'LSUBm' approximation scheme and we carry out high-order calculations by using intensive computational methods. We calculate the ground-state energy, the uniform susceptibility, the total (lattice) magnetization and the local (sublattice) magnetizations as a function of the magnetic field strength. Our results for the lattice magnetization of the square-lattice case compare well to the results from QMC approaches for all values of the applied external magnetic field. We find a value for the magnetic susceptibility of χ = 0.070 for the square-lattice antiferromagnet, which is also in agreement with the results from other approximate methods (e.g., χ = 0.0669 obtained via the QMC approach). Our estimate for the range of the extent of the (M/M(s) =) [Formula: see text] magnetization plateau for the triangular-lattice antiferromagnet is 1.37<λ<2.15, which is in good agreement with results from spin-wave theory (1.248<λ<2.145) and exact diagonalizations (1.38<λ<2.16). Our results therefore support those from exact diagonalizations that indicate that the plateau begins at a higher value of λ than that suggested by spin-wave theory (SWT). The CCM value for the in-plane magnetic susceptibility per site is χ = 0.065, which is below the result of SWT (evaluated to order 1/S) of χ(SWT) = 0.0794. Higher-order calculations are thus suggested for both SWT and CCM LSUBm calculations in order to determine the value of χ for the triangular lattice conclusively.

The impact of radiotherapy late effects on quality of life in gynaecological cancer patients

The aims of this study were to assess changes in quality of life (QoL) scores in relation to radical radiotherapy for gynaecological cancer (before and after treatment up to 3 years), and to identify the effect that late treatment effects have on QoL. This was a prospective study involving 225 gynaecological cancer patients. A QoL instrument (European Organisation for the Research and Treatment of Cancer QLQ-C30) and late treatment effect questionnaire (Late Effects Normal Tissues - Subjective Objective Management Analysis) were completed before and after treatment (immediately after radiotherapy, 6 weeks, 12, 24 and 36 months after treatment). Most patients had acute physical symptoms and impaired functioning immediately after treatment. Levels of fatigue and diarrhoea only returned to those at pre-treatment assessment after 6 weeks. Patients with high treatment toxicity scores had lower global QoL scores. In conclusion, treatment with radiotherapy for gynaecological cancer has a negative effect on QoL, most apparent immediately after treatment. Certain late treatment effects have a negative effect on QoL for at least 2 years after radiotherapy. These treatment effects are centred on symptoms relating to the rectum and bowel, for example, diarrhoea, tenesmus and urgency. Future research will identify specific symptoms resulting from late treatment toxicity that have the greatest effect on QoL; therefore allowing effective management plans to be developed to reduce these symptoms and improve QoL in gynaecological cancer patients.

Developing a CTCAEs patient questionnaire for late toxicity after head and neck radiotherapy

PURPOSE

Patient-based reporting of symptoms is increasingly important in providing treatment toxicity information. However, observer-based scoring systems such as the CTCAEs which incorporate the LENT-SOMA scales are not adapted for patient-based reporting. We aim to (1) report the late toxicity in patients following head and neck radiotherapy using a LENT-SOMA patient-based questionnaire, (2) describe how the responses help to improve the questionnaire and (3) adapt the questionnaire for patient reporting using CTCAEs.

METHODS

A 31-item LENT-SOMA patient questionnaire was administered prospectively to 220 patients pre-treatment and at eight time periods post-radical head and neck radiotherapy over 3 years. Exploratory factor analysis was carried out and questionnaire reliability was evaluated using Cronbach's alpha coefficient.

RESULTS

At 3-years follow-up, grade 3/4 toxicity was recorded for xerostomia (44%), hoarseness (14.3%), altered taste (6.1%) and oropharyngeal pain (1.9%). Factor analysis indicated that questionnaire division according to anatomical sub-site was reasonable. Cronbach's alpha was 0.851 (95% CI: 0.820-0.883) indicating high reliability. Good compliance was obtained with all questions except for the 'weight loss' item. A satisfaction survey showed that the questionnaire was clear and concise. Teeth and mandible sections have been removed. Dietary change due to xerostomia has been incorporated in line with CTCAEs. LENT-SOMA scoring of analgesic needs and dysphagia not described in CTCAEs were found useful and have been retained.

CONCLUSIONS

The questionnaire has enabled reporting of late toxicity and the responses have enabled refinement of the questionnaire. It is reliable, feasible and has been validated for patient-based collection of CTCAEs late toxicity data.

Detecting reduced bone mineral density from dental radiographs using statistical shape models

We describe a novel method of estimating reduced bone mineral density (BMD) from dental panoramic tomograms (DPTs), which show the entire mandible. Careful expert width measurement of the inferior mandibular cortex has been shown to be predictive of BMD in hip and spine osteopenia and osteoporosis. We have implemented a method of automatic measurement of the width by active shape model search, using as training data 132 DPTs of female subjects whose BMD has been established by dual-energy X-ray absorptiometry. We demonstrate that widths measured after fully automatic search are significantly correlated with BMD, and exhibit less variability than manual measurements made by different experts. The correlation is highest towards the lateral region of the mandible, in a position different from that previously employed for manual width measurement. An receiver-operator characterstic (ROC) analysis for identifying osteopenia (T < -1: BMD more than one standard deviation below that of young healthy females) gives an area under curve (AUC) value of 0.64. Using a minimal interaction to initiate active shape model (ASM) search, the measurement can be made at the optimum region of the mandible, resulting in an AUC value of 0.71. Using an independent test set, AUC for detection of osteoporosis (T < -2.5) is 0.81.

Monte Carlo simulation of latanoprost induced iris darkening

The aim of this study was to provide numerical evidence that latanoprost induced iris darkening (LIID) can be caused by changes to the melanin granule size distribution in the anterior segment of the iris. Iridectomies from two patients were used, where both had undergone unilateral treatment with latanoprost and had exhibited LIID. The untreated eye provided the comparative control. Micrographs from the iris samples were analysed to determine the number and size of the mature melanin granules. Monte Carlo (MC) simulation of light propagation in the iris was performed to examine the changes in reflectance and absorption with varying particle size and density. The reflected intensity of light was obtained as a function of wavelength. CIE colour theory was employed in order to estimate a perceived colour from the reflectance data. MC simulations showed that the reflectance was reduced for the LIID irises compared to the control irises for both subjects and for all wavelengths of light. The MC simulated colours were in good agreement with the in vivo photography of the eye colour. Hence, we have demonstrated that increases in melanin granule size causes iris darkening, and can explain LIID.

Numerical model of self-propulsion in a fluid

We provide initial evidence that a structure formed from an articulated series of linked elements, where each element has a given stiffness, damping and driving term with respect to its neighbours, may 'swim' through a fluid under certain conditions. We derive a Lagrangian for this system and, in particular, we note that we allow the leading edge to move along the x-axis. We assume that no lateral displacement of the leading edge of the structure is possible, although head 'yaw' is allowed. The fluid is simulated using a computational fluid dynamics technique, and we are able to determine and solve Euler-Lagrange equations for the structure. These two calculations are solved simultaneously by using a weakly coupled solver. We illustrate our method by showing that we are able to induce both forward and backward swimming. A discussion of the relevance of these simulations to a slowly swimming body, such as a mechanical device or a fish, is given.