Hierarchical Clustering Applied to Chronic Pain Drawings Identifies Undiagnosed Fibromyalgia: Implications for Busy Clinical Practice

Currently-used assessments for fibromyalgia require clinicians to suspect a fibromyalgia diagnosis, a process susceptible to unintentional bias. Automated assessments of standard patient-reported outcomes (PROs) could be used to prompt formal assessments, potentially reducing bias. We sought to determine whether hierarchical clustering of patient-reported pain distribution on digital body map drawings predicted fibromyalgia diagnosis. Using an observational cohort from the University of Pittsburgh's Patient Outcomes Repository for Treatment registry, which contains PROs and electronic medical record data from 21,423 patients (March 17, 2016-June 25, 2019) presenting to pain management clinics, we tested the hypothesis that hierarchical clustering subgroup was associated with fibromyalgia diagnosis, as determined by ICD-10 code. Logistic regression revealed a significant relationship between the body map cluster subgroup and fibromyalgia diagnosis. The cluster subgroup with the most body areas selected was the most likely to receive a diagnosis of fibromyalgia when controlling for age, gender, anxiety, and depression. Despite this, more than two-thirds of patients in this cluster lacked a clinical fibromyalgia diagnosis. In an exploratory analysis to better understand this apparent underdiagnosis, we developed and applied proxies of fibromyalgia diagnostic criteria. We found that proxy diagnoses were more common than ICD-10 diagnoses, which may be due to less frequent clinical fibromyalgia diagnosis in men. Overall, we find evidence of fibromyalgia underdiagnosis, likely due to gender bias. Coupling PROs that take seconds to complete, such as a digital pain body map, with machine learning is a promising strategy to reduce bias in fibromyalgia diagnosis and improve patient outcomes. PERSPECTIVE: This investigation applies hierarchical clustering to patient-reported, digital pain body maps, finding an association between body map responses and clinical fibromyalgia diagnosis. Rapid, computer-assisted interpretation of pain body maps would be clinically useful in prompting more detailed assessments for fibromyalgia, potentially reducing gender bias.

Tooth loss is associated with prevalent diabetes and incident diabetes in a longitudinal study of adults in Ireland

AIM

The aim of this study was to explore the relationship between periodontal status, tooth loss and diabetes among community-dwelling adults aged 50 years and over in Ireland.

METHODS

From respondents who attended a health assessment in Wave 3 of the Irish Longitudinal Study on Ageing (TILDA), an opportunistic sample was selected for an oral health examination. The oral health examination criteria were used in previous Irish surveys and WHO recommendations. For diabetes, the self-reported and objectively measured data on diabetes for the same cohort from Wave 3 to Wave 5 of TILDA was used. Multinomial regression analysis was used to evaluate the relationship between diabetes and tooth loss and tooth loss and incident diabetes, controlling for other covariates.

RESULTS

Out of the 3111 people who were offered an oral health assessment 2539 were examined. For the purposes of analysis, the adults below 50 years of age (n = 31) and those with an incomplete oral health assessment (n = 4) were omitted from the sample. The final sample consisted of 2504 people, giving a response rate of 80.5%. Among the study sample, 9.9% (n = 249) were edentate; 35.7% (n = 895) had 1-19 teeth and 54.4% (n = 1360) had ≥20 teeth. From the sample of 2504 adults, 2358 had HbA1c results and 8.4% (n = 198) of these had diabetes according to the TILDA criteria. Multinomial regression analysis showed that diabetes was associated with tooth loss. Diabetes at Wave 3 was associated with a higher rate of being edentate (PR 2.12, 95% CI 1.27-3.52) relative to having ≥20 teeth while controlling for the effect of age, gender, education level, area of residence, body mass index (BMI) and smoking. Furthermore, having 1-19 teeth at Wave 3 was associated with incident diabetes over a 4-year follow-up (OR 1.94, 1.00-3.75). There was no evidence of an association between diabetes and periodontal status as measured in this sample.

CONCLUSION

The results suggested that diabetes was associated with tooth loss and that this relationship may be bi-directional among community-dwelling adults aged 50 years and over in Ireland, but they do not support a relationship between diabetes and periodontal status in this sample.

Idiopathic granulomatous mastitis: a 5-year retrospective review of cases in a tertiary centre in Dublin, Ireland

AIMS

Idiopathic granulomatous mastitis (IGM) is a rare, benign, inflammatory breast disorder of unknown aetiology usually affecting women of reproductive age. It classically presents as a unilateral painful breast mass. It is frequently mistaken for carcinoma or other inflammatory breast diseases. Diagnostic investigations include clinical examination, appropriate imaging and tissue sampling. A link between IGM and infection with the Corynebacterium species in particular Corynebacterium kroppenstedtii has been described.

METHODS

A retrospective single-centre cohort study was conducted over a 5-year period (2017-2022); all cases of IGM were identified.

RESULTS

Forty-one patients were diagnosed with IGM. Breast lump was the most common presenting complaint (n=29). The average age was 45 years. Eighteen patients had samples sent for culture and sensitivity, 11 of which had positive microbiology results indicative of Corynebacterium spp infection.An 82% resolution rate (27 of 33) was recorded in those who received either a short-antibiotic course or none at all. Eight patients reported persistent disease at 3 months, five of which had evidence of Corynebacterium spp.

DISCUSSION

This 5-year review highlights the impact of IGM in a tertiary centre in Dublin, Ireland. Although no treatment guidelines exist, options include antibiotics, immunomodulators and surgery. Due to risk of fistulae and unfavourable cosmetic outcomes, surgery should be reserved for refractory IGM. We suspect that there may be a subset of patients where prolonged antibiotic therapy should be considered. Defining this subgroup requires further study, but likely includes those with cystic neutrophilic granulomatous mastitis, relapsing disease and in whom Corynebacterium spp is recovered.

An electronic medical record reminder is independently associated with improved opportunistic influenza vaccination rates for older inpatients

BACKGROUND

Influenza vaccination will have added importance this winter given the possibility of further waves of the COVID-19 pandemic. This study examines the impact of an electronic medical record (EMR) reminder on influenza vaccine uptake among eligible hospital inpatients.

METHODS

We included a convenience sample of 750 adults (median age 77 years) who are eligible for influenza vaccination (⩾65 years and/or length of stay >30 days). A live electronic dashboard identified patients eligible for vaccination, prompting reminders sent to the clinical teams via the EMR.

RESULTS

The EMR reminder was associated with almost a 50% higher likelihood of vaccination after adjusting for other covariates (odds ratio 1.48 (95% confidence interval 1.00-2.20); p = 0.048).

DISCUSSION

Reminders sent to the clinical team via the EMR appear to be an effective means of increasing vaccine uptake and should be considered as part of this year's drive to vaccinate eligible patients in hospital.

Implementation of a food science and nutrition module in a dental undergraduate curriculum

INTRODUCTION

To outline the development and implementation of a food science and nutrition module for dental undergraduate students that provides basic knowledge and clinical skills for improving oral health outcomes and understanding their importance for overall health.

MATERIALS AND METHODS

Interdisciplinary discussions with professionals with expertise in food science and nutrition, including dentists, dietitians and nutritionists, were held to agree on core subject areas in line with the evidence base. The module was delivered online to 2nd-year dental students due to COVID-19 restrictions. Students completed an online evaluation on completing the module. Final examination consisted of one essay question.

RESULTS

Subject areas and learning outcomes were derived from current and previous approaches to curriculum development. A total of 14 prerecorded lectures, including healthy eating guidelines, dietary assessment, specific oral effects of diet and food constituents were delivered and tutorials provided. The evaluation survey had a 90% (n = 39/43) response rate. A majority indicated that the course was "interesting," "worth doing" (59%) and "provided a good evidence base to understand nutrition and oral health" (87%). Nearly all students (92%) agreed that the course was "sufficiently structured to allow understanding of the key topics" and that "a good understanding of nutrition is important for a dentist" (95%).

CONCLUSION

A food science and nutrition module developed by a multidisciplinary team enabled dental students to gain an understanding of the role of diet in oral and overall health. The module facilitated the development of skills that enable students to utilise dietary assessment techniques and promote dietary interventions beneficial to oral health. The approach taken may act as a template for other institutions.

Tooth loss and regional grey matter volume

OBJECTIVES

To investigate whether tooth loss was associated with regional grey matter volume (GMV) in a group of community dwelling older men and women from Ireland.

METHODS

A group of 380 dementia-free men and women underwent a dental examination and had a Magnetic Resonance Imaging (MRI) scan as part of The Irish Longitudinal Study of Aging (TILDA). Cortical parcellation was conducted using Freesurfer utilities to produce volumetric measures of gyral based regions of interest. Analysis included multiple linear regression to investigate the association between tooth loss and regional GMVs with adjustment for various confounders.

RESULTS

The mean age of participants was 68.1 years (SD 7.3) and 51.6% of the group were female. 50 (13.2%) of the participants were edentulous, 148 (38.9%) had 1-19 teeth, and 182 (47.9%) had ≥20 teeth. Multiple liner regression analysis with adjustment for a range of potential confounders showed associations between the number of teeth and GMVs in the paracentral lobule and the cuneus cortex. In the paracentral lobule, comparing participants with 1-19 teeth versus edentates there was an increase in GMV of β=323.0mm³ (95% Confidence Interval [CI] 84.5, 561.6) and when comparing participants with ≥20 teeth to edentates there was an increase of β=382.3mm³ (95% CI 126.9, 637.7). In the cuneus cortex, comparing participants with ≥20 teeth to edentates there was an increase in GMV of β=380.5mm³ (95% CI 69.4, 691.5).

CONCLUSIONS

In this group of older men and women from Ireland, the number of teeth was associated with GMVs in the paracentral lobule and the cuneus cortex independent of various known confounders.

CLINICAL SIGNIFICANCE

Although not proof of causation, the finding that tooth loss was associated with regional reduced GMV in the brain may represent a potential explanatory link to the observed association between tooth loss and cognitive decline.

An emerging Panton-Valentine leukocidin-positive CC5-meticillin-resistant Staphylococcus aureus-IVc clone recovered from hospital and community settings over a 17-year period from 12 countries investigated by whole-genome sequencing

BACKGROUND

A novel Panton-Valentine leukocidin (PVL)-positive meticillin-resistant Staphylococcus aureus (MRSA) clonal complex (CC)5-MRSA-IVc ('Sri Lankan' clone) was recently described from Sri Lanka. Similar isolates caused a recent Irish hospital outbreak.

AIM

To investigate the international dissemination and diversity of PVL-positive CC5-MRSA-IVc isolates from hospital and community settings using whole-genome sequencing (WGS).

METHODS

Core-genome single nucleotide polymorphism (cgSNP) analysis, core-genome multi-locus sequence typing (cgMLST) and microarray-based detection of antimicrobial-resistance and virulence genes were used to investigate PVL-positive CC5-MRSA-IVc (N = 214 including 46 'Sri Lankan' clone) from hospital and community settings in 12 countries over 17 years. Comparators included 29 PVL-positive and 23 PVL-negative CC5/ST5-MRSA-I/II/IVa/IVc/IVg/V.

RESULTS

Maximum-likelihood cgSNP analysis grouped 209/214 (97.7%) CC5-MRSA-IVc into Clade I; average of 110 cgSNPs between isolates. Clade III contained the five remaining CC5-MRSA-IVc; average of 92 cgSNPs between isolates. Clade II contained seven PVL-positive CC5-MRSA-IVa comparators, whereas the remaining 45 comparators formed an outlier group. Minimum-spanning cgMLST analysis revealed a comparably low average of 57 allelic differences between all CC5/ST5-MRSA-IVc. All 214 CC5/ST5-MRSA-IVc were identified as 'Sri Lankan' clone, predominantly spa type t002 (186/214) with low population diversity and harboured a similar range of virulence genes and variable antimicrobial-resistance genes. All 214 Sri Lankan clone isolates and Clade II comparators harboured a 9616-bp chromosomal PVL-encoding phage remnant, suggesting both arose from a PVL-positive meticillin-susceptible ancestor. Over half of Sri Lankan clone isolates were from infections (142/214), and where detailed metadata were available (168/214), most were community associated (85/168).

CONCLUSIONS

Stable chromosomal retention of pvl may facilitate Sri-Lankan clone dissemination.

The psychological burden of disease among patients undergoing cervical spine surgery: Are we underestimating our patients' inherent disability?

BACKGROUND

Studies have utilized psychological questionnaires to identify the psychological distress among certain surgical populations.

RESEARCH QUESTION

Is there an additional psychological burden among patients undergoing surgical treatment for their symptomatic degenerative cervical disease?

MATERIALS AND METHODS

Patients>18 years of age with symptomatic, degenerative cervical spine disease were included and prospectively enrolled. Correlations and multivariable logistic regression analysis assessed the relationship between these mental health components (PCS, FABQ) and the severity of disability described by the NDI, EQ-5D, and mJOA score. Patient distress scores were compared to previously published benchmarks for other diagnoses.

RESULTS

47 patients were enrolled (age: 56.0 years,BMI: 29.7kg/m²). Increasing neck disability and decreasing EQ-5D were correlated with greater PCS and FABQ(all P<0.001). Patients with severe psychological distress at baseline were more likely to report severe neck disability, while physician-reported mJOA had weaker associations. Compared to historical controls of lumbar patients, patients in our study had greater levels of psychological distress, as measured by FABQ (40.0 vs. 17.6; P<0.001) and PCS (27.4 vs. 19.3;P<0.001).

DISCUSSION AND CONCLUSION

Degenerative cervical spine patients seeking surgery were found to have a significant level of psychological distress, with a large portion reporting severe fear avoidance beliefs and catastrophizing pain at baseline. Strong correlation was seen between patient-reported functional metrics, but less so with physician-reported signs and symptoms. Additionally, this population demonstrated higher psychological burden in certain respects than previously identified benchmarks of patients with other disorders. Preoperative treatment to help mitigate this distress, impact postoperative outcomes, and should be further investigated.

LEVEL OF EVIDENCE

Level III.

Mapping the graduating European dentist to established undergraduate dental education activities at Trinity College Dublin

INTRODUCTION

"The Graduating European Dentist" Curriculum (GED) was adopted in 2020 by the Irish Dental Council as its new expectation for competencies. The Dublin Dental University Hospital (DDUH) sought to map the teaching activities for its undergraduate dental training programme to the GED. This paper describes the process developed for curriculum mapping.

MATERIALS AND METHODS

Guided by historical mapping data and materials on the DDUH's virtual learning environment; teaching activities in a bespoke curriculum mapping system were edited, added and/or deleted to match existing teaching activities currently delivered by staff to students. These activities were then remapped to GED Learning Outcomes. Staff members with oversight responsibilities for a collection of activities then received and provided feedback on reports tabulating the preliminary map. Feedback from staff members around their activities was accommodated to produce an accurate reflection of teaching activities across the 5 years program.

RESULTS

A process for mapping existing teaching activities to a new set of curriculum expectations using a bespoke application and several other widely available technologies was established. Informal feedback from staff has been positive and has raised ideas for future opportunities to improve the alignment of educational activities with learning outcomes.

CONCLUSION

Other dental schools may find this accounting of the DDUH's efforts useful in guiding their own curriculum mapping.

Dental health status of community-dwelling adults aged 50 years and over in Ireland. A cross-sectional analysis of the Wave 3 TILDA cohort

Background: Little is known about the current oral health status of adults in Ireland. The aim of this study was to assess the dental health of community-dwelling adults aged 50 years and over in Ireland and to compare the current status to previous national surveys.  Methods: The Irish Longitudinal Study on Ageing (TILDA) Wave 3 assessed the dental health of a subset of participants. Respondents attending for health assessments were offered a dental examination. The World Health Organization examination criteria were used. Results: Of the 3111 people who were offered the dental assessment, 2525 were examined. Adults below 50 years of age and respondents whose dental health data were unavailable at the time of analysis were omitted, giving a final sample of 2504.  Among the dental assessment sample, 9.9% (249) were edentate. Of those aged 65 years and older, 15.6% were edentate while for the same age group 40.9% were edentate in the 2000-02 national survey. The mean number of teeth present in those aged 65 years or older was 14.9 for males and 14.2 for females, whereas in 2000-02 it was 9.9 and 7.4, respectively.  56.8% of the dentate sample had 10 or more tooth contacts. The mean DMFT of those aged 50 years or more was 18.5 and the Root Caries Index was 6.3. Between 2000-02 and 2014-5 (this study) in adults aged 65 years and over, the mean DMFT decreased from 25.9 to 20.1 and the Root Caries Index decreased from 11.6 to 9.1. Conclusion: The results indicate the dental health of community-dwelling adults aged 50 years and over in Ireland improved since the previous survey of 2000-02. These improvements mean a change in the treatment needs of this age group and will require policy and service adjustments to meet these needs

Prospective study of surgical site infections post-open esophageal cancer surgery, and the impact of care bundles

SSIs represent common infection-related morbidity following major surgery. Modern care bundles have been established as prophylactic measures aimed at preventing SSI occurring postoperatively. SSI incidence and data on common culprit pathogens post-esophagectomy for cancer have not been previously reported. Patients (2013-2018) treated with curative intent were studied. SSI was defined as per the Center for Disease Control (CDC) definition. A care bundle pathway following the National Institute for Clinical Excellence (NICE) guidelines for prevention of SSIs was introduced in 2013 and was audited quarterly. Risk factors and associations of SSIs were analyzed, as was the prevalence of isolated pathogens. Multivariable logistic regression examined independently predictive factors of SSIs and oncologic outcomes. Of 343 patients, 34 (9.9%) developed a postoperative SSI, with a median (range) of 8 (6-17). Quarterly audit carried out over 6 years showed no significant annual variance or trend. The most prevalent pathogen cultured was Methicillin-sensitive Staphylococcus aureus (MSSA) in nine patients (32%) followed by Candida albicans (29%), Escherichia coli (14%), and Enterococcus faecium (11%). SSI was significantly associated with pneumonia (P = 0.001), respiratory failure (P = 0.014), atrial fibrillation (P = 0.004), anastomotic leak (P < 0.001), and in-hospital blood transfusions (P = 0.031). SSI did not impact the overall survival (P = 0.951). SSI rates can be maintained at less than 10% using strict care bundles and regular audit. The most common culprit pathogen is gram-positive MSSA representing 32% of cases. These data are novel and may represent a modern benchmark for SSI post-open esophagectomy for cancer. This study highlights the incidence and associations of SSI post-esophageal cancer surgery.

216 IMPROVING INPATIENT INFLUENZA VACCINATION RATES—THE VALUE OF AN ELECTRONIC PATIENT RECORD REMINDER SYSTEM

Background

Influenza vaccination, particularly for vulnerable, older adults, will have added importance this winter given the possibility of further waves of COVID-19 pandemic. Previous interventions at the study site noted poor awareness on the need for inpatient Influenza vaccination¹. This study examines a vaccination reminder process using an electronic patient record (EPR) to identify high-priority eligible inpatients.

Methods

The study site is a 900-bed university teaching hospital with all clinical notes accessed via an EPR.

We included a convenience sample of 750 adults aged≥50 years (mean age 75.9 +/− 0.4 years, 48% female) and high-priority for influenza vaccination (Age > 65 years and/or length of stay (LOS) >30 days) from October 1^st 2020 to January 12^th 2021.

A live electronic dashboard identified eligible inpatients for vaccination, prompting vaccination reminders to the clinical teams via the antimicrobial pharmacist.

Data was collected retrospectively. Logistic regression models reporting odds ratios were used to assess the association of these reminders with vaccine uptake.

Results

Over one third (35%, 264/750) of high-priority patients received the Influenza vaccine while inpatients, including 40% aged ≥80 years.

The reminder was sent on 41% (305/750) of patients and was associated with an almost 50% higher likelihood of vaccination after adjusting for other covariates (Odds Ratio 1.48 (95% CI 1.00–2.20); p = 0.048).

Other factors independently associated with vaccination were advancing age (Odds Ratio 2.69 (95% CI 1.12–6.47) for age ≥ 80 years); LOS (4% higher likelihood of vaccination for every additional day in hospital) and admission under geriatric medicine (Odds Ratio 3.71 (95% CI 2.45–5.62) when compared to other specialities).

Conclusion

Our study shows relatively low uptake of inpatient Influenza vaccination and strategies to improve uptake are required. Reminders sent to clinical teams using the EPR appear to be an effective means of increasing Influenza vaccination and should be considered as part of this year’s inpatient vaccination drive.

Dental health status of community-dwelling adults aged 50 years and over in Ireland. A cross-sectional analysis of the Wave 3 TILDA cohort

Background: Little is known about the current oral health status of adults in Ireland. The aim of this study was to assess the dental health of community-dwelling adults aged 50 years and over in Ireland and to compare the current status to previous national surveys.  Methods: The Irish Longitudinal Study on Ageing (TILDA) Wave 3 assessed the dental health of a subset of participants. Respondents attending for health assessments were offered a dental examination. The World Health Organization examination criteria were used. Results: Of the 3111 people who were offered the dental assessment, 2525 were examined. Adults below 50 years of age and respondents whose dental health data were unavailable at the time of analysis were omitted, giving a final sample of 2504.  Among the dental assessment sample, 9.9% (249) were edentate. Of those aged 65 years and older, 15.6% were edentate while for the same age group 40.9% were edentate in the 2000-02 national survey. The mean number of teeth present in those aged 65 years or older was 14.9 for males and 14.2 for females, whereas in 2000-02 it was 9.9 and 7.4, respectively.  56.8% of the dentate sample had 10 or more tooth contacts. The mean DMFT of those aged 50 years or more was 18.5 and the Root Caries Index was 6.3. Between 2000-02 and 2014-5 (this study) in adults aged 65 years and over, the mean DMFT decreased from 25.9 to 20.1 and the Root Caries Index decreased from 11.6 to 9.1. Conclusion: The results indicate improvements in the dental health of community-dwelling adults aged 50 years and over in Ireland as compared to the previous survey of 2000-02. These improvements mean a change in the treatment needs of this age group and will require policy and service adjustments to meet these needs

Linezolid resistance in Enterococcus faecium and Enterococcus faecalis from hospitalized patients in Ireland: high prevalence of the MDR genes optrA and poxtA in isolates with diverse genetic backgrounds

OBJECTIVES

To investigate the prevalence of the optrA, poxtA and cfr linezolid resistance genes in linezolid-resistant enterococci from Irish hospitals and to characterize associated plasmids.

METHODS

One hundred and fifty-four linezolid-resistant isolates recovered in 14 hospitals between June 2016 and August 2019 were screened for resistance genes by PCR. All isolates harbouring resistance genes, and 20 without, underwent Illumina MiSeq WGS. Isolate relatedness was assessed using enterococcal whole-genome MLST. MinION sequencing (Oxford Nanopore) and hybrid assembly were used to resolve genetic environments/plasmids surrounding resistance genes.

RESULTS

optrA and/or poxtA were identified in 35/154 (22.7%) isolates, the highest prevalence reported to date. Fifteen isolates with diverse STs harboured optrA only; one Enterococcus faecium isolate harboured optrA (chromosome) and poxtA (plasmid). Seven Enterococcus faecalis and one E. faecium harboured optrA on a 36 331 bp plasmid with 100% identity to the previously described optrA-encoding conjugative plasmid pE349. Variations around optrA were also observed, with optrA located on plasmids in five isolates and within the chromosome in three isolates. Nine E. faecium and 10 E. faecalis harboured poxtA, flanked by IS1216E, within an identical 4001 bp region on plasmids exhibiting 72.9%-100% sequence coverage to a 21 849 bp conjugative plasmid. E. faecalis isolates belonged to ST480, whereas E. faecium isolates belonged to diverse STs. Of the remaining 119 linezolid-resistant isolates without linezolid resistance genes, 20 investigated representatives all harboured the G2576T 23S RNA gene mutation associated with linezolid resistance.

CONCLUSIONS

This high prevalence of optrA and poxtA in diverse enterococcal lineages in Irish hospitals indicates significant selective pressure(s) for maintenance.

Epidemiological typing of methicillin resistant Staphylococcus aureus recovered from patients attending a maternity hospital in Ireland 2014-2019

It has previously been reported that maternity hospitals have lower levels of MRSA compared to other healthcare facilities, due to the patient population - mostly healthy patients with limited healthcare contact. In this epidemiological study, all MRSA isolates recovered from patients attending a maternity hospital from 2014 – 2019 were investigated. 171 isolates from adults (n=120) and babies (n=51) from diagnostic and screening investigations were submitted to the National MRSA Reference Laboratory (NMRSARL). Investigations included: spa typing, antimicrobial susceptibility testing, detection of the mecA/mecC genes and lukS-PV and lukF-PV. All were susceptible to glycopeptides, linezolid, rifampicin and mupirocin, while 29 of 171 (17%) were resistant to β-lactam agents only. Thirteen isolates (8%) were resistant to two classes of antibiotic; one resistant to three. All isolates harboured mecA and 33 of 171 (19%) harboured PV-lukF/S. Among the collection, 21 multilocus sequence types (ST) were inferred from 63 spa types. EARS-NET data shows that ST22-MRSA-IV accounts for approximately 75% of MRSA recovered in Irish hospitals. Here, it accounted for only 25.7%. MLST types associated with community acquired MRSA accounted for the remaining 74.3%. These included ST8, ST30, ST1, ST5 and ST88, suggesting a diverse population, harbouring multiple resistance and virulence genes, some of which have been previously associated with outbreaks in Ireland. This study exposes a reservoir of MRSA in the community which may be imported into hospitals, leading to outbreaks. The diversity of MRSA lineages with enhanced virulence factors highlights the need for regular surveillance to ensure appropriate infection prevention and control interventions are implemented promptly.

Multiple distinct outbreaks of Panton-Valentine leucocidin-positive community-associated meticillin-resistant Staphylococcus aureus in Ireland investigated by whole-genome sequencing

BACKGROUND

Panton-Valentine leucocidin (PVL)-positive community-associated meticillin-resistant Staphylococcus aureus (CA-MRSA) is increasingly associated with infection outbreaks.

AIM

To investigate multiple suspected PVL-positive CA-MRSA outbreaks using whole-genome sequencing (WGS).

METHODS

Forty-six suspected outbreak-associated isolates from 36 individuals at three separate Irish hospitals (H1-H3) and from separate incidents involving separate families associated with H2 were investigated by whole-genome multi-locus sequence typing (wgMLST).

FINDINGS

Two clusters (CH1 and CH2) consisting of 8/10 and 6/6 PVL-positive t008 ST8-MRSA-IVa isolates from H1 and H2, respectively, were identified. Within each cluster, neighbouring isolates were separated by ≤5 allelic differences; however, ≥73 allelic differences were identified between the clusters, indicating two independent outbreaks. Isolates from the H3 maternity unit formed two clusters (CH3-SCI and CH3-SCII) composed of four PVL-negative t4667 ST5-MRSA-V and 14 PVL-positive t002 ST5-MRSA-IVc isolates, respectively. Within clusters, neighbouring isolates were separated by ≤24 allelic differences, whereas both clusters were separated by 1822 allelic differences, indicating two distinct H3 outbreaks. Eight PVL-positive t127 ST1-MRSA-V+fus and three PVL-negative t267 ST97-MRSA-V+fus isolates from two distinct H2-associated families FC1 (N = 4) and FC2 (N = 7) formed three separate clusters (FC1 (t127), FC2 (t127) and FC2 (t267)). Neighbouring isolates within clusters were closely related and exhibited ≤7 allelic differences. Intrafamilial transmission was apparent, but the detection of ≥48 allelic differences between clusters indicated no interfamilial transmission.

CONCLUSION

The frequent importation of PVL-positive CA-MRSA into healthcare settings, transmission and association with outbreaks is a serious ongoing concern. WGS is a highly discriminatory, informative method for deciphering such outbreaks conclusively.

A Surviving Case of Acanthamoeba Granulomatous Amebic Encephalitis in a Hematopoietic Stem Cell Transplant Recipient

BACKGROUND Acanthamoeba are free-living amoebae with potential to infect immunocompromised hosts. The mortality rate of granulomatous amebic encephalitis (GAE) due to Acanthamoeba exceeds 90% and there are currently no reports of survival of this infection in recipients of hematopoietic stem cell transplant. CASE REPORT We report herein the case of a 32-year-old man presenting to our service with abrupt neurological deterioration and seizures 5 months after allogeneic stem cell transplantation for Hodgkin lymphoma. Clinical and imaging findings were non-specific at presentation. Multiple circumscribed, heterogenous, mass-like lesions were identified on MRI. Brain biopsy was performed and revealed multiple cysts and trophozoites suggesting a diagnosis of granulomatous amebic encephalitis. PCR testing confirmed Acanthamoeba. Treatment with miltefosine, metronidazole, azithromycin, fluconazole, pentamidine isethionate, and co-trimoxazole was instituted and the patient survived and shows continued improvement with intensive rehabilitation. CONCLUSIONS We report the first successful outcome in this setting. The diagnosis would have been missed on cerebrospinal fluid analysis alone, but was rapidly made by histological analysis of brain biopsy. This diagnostically challenging infection is likely under-recognized. Early brain biopsy and commencement of a prolonged miltefosine-containing anti-ameba regimen can be curative.

An Investigation of the Characteristics of Edentulous Patients Who Choose or Refuse Implant Treatment

PURPOSE

To investigate whether pretreatment patient satisfaction, oral health-related quality of life, or diagnostic complexity are predictive of a decision to choose implant treatment.

MATERIALS AND METHODS

Edentulous patients requesting dentures were enrolled in a prospective observational study. All subjects were provided with conventional dentures and then given the option to proceed with the placement of two mandibular implants and to have their prosthesis modified into an implant overdenture. Subjects were classified according to the Prosthodontic Diagnostic Index (PDI-CE) and asked to complete a Denture Satisfaction Questionnaire and the Oral Health Impact Profile for edentulous patients (OHIP-EDENT) at pretreatment, following the provision of new dentures, and following modification to overdentures.

RESULTS

Of the 125 subjects who had conventional dentures, 15 proceeded with implant treatment. The subjects who decided to have implants were not significantly different in terms of diagnostic complexity or level of satisfaction. Those who chose implants were significantly younger, had newer dentures, and had higher OHIP-EDENT scores at baseline. The most common reason for not being satisfied with dentures but avoiding implants was fear of surgery.

CONCLUSION

The majority of subjects in this study were satisfied with conventional denture treatment, despite registering its limitations. Subjects who were more anatomically compromised were not more likely to choose implant treatment. It remains to be shown whether fear of surgery can be overcome in order to increase the uptake of implant treatment and improve patient outcomes.

Hospital outbreak of linezolid-resistant and vancomycin-resistant ST80 Enterococcus faecium harbouring an optrA-encoding conjugative plasmid investigated by whole-genome sequencing

BACKGROUND

Linezolid is an antibiotic used to treat infections caused by multi-drug-resistant Gram-positive bacteria. Linezolid resistance in enterococci has been reported with increasing frequency, with a recent rise in resistance encoded by optrA, poxtA or cfr.

AIM

To investigate a hospital outbreak of linezolid- and vancomycin-resistant Enterococcus faecium (LVREfm) using whole-genome sequencing (WGS).

METHODS

Thirty-nine VREfm from patient screening (19 isolates, 17 patients) and environmental sites (20 isolates) recovered in October 2019 were investigated. Isolates were screened using polymerase chain reaction for optrA, poxtA and cfr, and underwent Illumina MiSeq WGS. Isolate relatedness was assessed using E. faecium core genome multi-locus sequence typing (cgMLST). One LVREfm underwent MinION long-read WGS (Oxford Nanopore Technologies) and hybrid assembly with MiSeq short-read sequences to resolve an optrA-encoding plasmid.

FINDINGS

Twenty isolates (51.3%) were LVREfm and optrA-positive, including the LVREfm from the index patient. A closely related cluster of 28 sequence type (ST) 80 isolates was identified by cgMLST, including all 20 LVREfm and eight linezolid-susceptible VREfm, with an average allelic difference of two (range 0-10), indicating an outbreak. Nineteen (95%) LVREfm harboured a 56,684-bp conjugative plasmid (pEfmO_03). The remaining LVREfm exhibited 44.1% sequence coverage to pEfmO_03. The presence of pEfmO_03 in LVREfm and the close relatedness of the outbreak cluster isolates indicated the spread of a single strain. The outbreak was terminated by enhanced infection prevention and control (IPC) and environmental cleaning measures, ceasing ward admissions and ward-dedicated staff.

CONCLUSION

WGS was central in investigating an outbreak of ST80 LVREfm. The rapid implementation of enhanced IPC measures terminated the outbreak.

Prognostic Value Of Blood Cultures as an Illness Severity Marker In Emergency Medical Admissions

BACKGROUND

Positive blood cultures predict mortality. The prognostic value of blood culture performance itself has not been fully defined.

METHODS

We evaluated medical admissions from 2002-2017. We defined blood culture category as 1) no culture 2) negative culture 3) positive culture. We employed a multivariable logistic regression model to evaluate outcomes.

RESULTS

We evaluated 78,568 blood cultures in 106,586 admissions. 30-day in-hospital mortality for no culture was 2.8% (95%CI 2.7, 2.9), culture negative 8.9% (95%CI 8.5, 9.3) and culture positive 16.7% (95%CI 15.5, 17.9). There was significant interaction between blood culture category and illness severity, OR 1.06 (95%CI 1.05, 1.08), and comorbidity, OR 1.09 (95%CI 1.09, 1.10).

CONCLUSION

Performance and results of blood cultures are independently associated with increased mortality.

Bartonella clarridgeiae infection in a patient with aortic root abscess and endocarditis

Introduction.

Bartonella species are increasingly recognized as agents of culture-negative endocarditis. However, to date, almost all human cases have been associated with two members of the genus, Bartonella henselae and Bartonella quintana. B. henselae infections are zoonotic, with domestic cats serving as reservoir hosts for the pathogen. Bartonella clarridgeiae also exploits cats as reservoir hosts, but its zoonotic potential is far less established.

Case presentation.

A 34-year-old male presented with palpitations after a history of aortic incompetence. During surgery for an aortic valve replacement, two vegetations were found on the aortic valve. PCR analysis of the vegetation demonstrated the presence of Bartonella species and so the patient was treated post-operatively with ceftriaxone and doxycycline, making a good recovery. Further PCR-based analysis of the patient’s aortic vegetation confirmed the presence of B. clarridgeiae.

Conclusion.

This report expands the number of Bartonella species associated with endocarditis and provides clear evidence that B. clarridgeiae should be considered a zoonotic pathogen.

Infective endocarditis: a retrospective cohort study

BACKGROUND

Infective endocarditis (IE) is a potentially life-threatening infection of the heart's endocardial surface. Despite advances in the diagnosis and management of IE, morbidity and mortality remain high.

AIM

To characterize the demographics, bacteriology and outcomes of IE cases presenting to an Irish tertiary referral centre.

DESIGN

Retrospective cohort study.

METHODS

Patients were identified using Hospital Inpatient Enquiry and Clinical Microbiology inpatient consult data, from January 2005 to January 2014. Patients were diagnosed with IE using Modified Duke Criteria. Standard Bayesian statistics were employed for analysis and cases were compared to contemporary international registries.

RESULTS

Two hundred and two patients were diagnosed with IE during this period. Mean age 54 years. Of these, 136 (67%) were native valve endocarditis (NVE), 50 (25%) were prosthetic valve endocarditis (PVE) and 22 (11%) were cardiovascular implantable electronic device-associated endocarditis. Culprit organism was identified in 176 (87.1%) cases and Staphylococcal species were the most common (57.5%). Fifty-nine per cent of NVE required surgery compared to 66% of PVE. Mean mortality rate was 17.3%, with NVE being the lowest (12.5%) and PVE the highest (32%). Increasing age was also associated with increased mortality. Fifty-three (26.2%) patients had embolic complications.

CONCLUSIONS

This Irish cohort exhibited first-world demographic patterns comparable to those published in contemporary international literature. PVE required surgery more often and was associated with higher rates of mortality than NVE. Embolic complications were relatively common and represent important sequelae, especially in the intravenous drug user population. It is also pertinent to aggressively treat older cohorts as they were associated with increased mortality.

Oral health status of community dwelling adults aged 50 years and over in Ireland. A cross-sectional analysis of the Wave 3 TILDA cohort

Background: Little is known about the current oral health status of adults in Ireland. The aim of this study was to measure the oral health status of community dwelling adults aged 50 years and over in Ireland, and to compare the current status to previous surveys of oral health in adults.  Methods: The Irish Longitudinal Study on Ageing (TILDA) Wave 3 provided an opportunity to assess the oral health of a subset of TILDA participants. Respondents attending for health assessments at the TILDA centre were offered an oral health examination. The World Health Organization examination criteria were used. Results: Out of the 3111 people who were offered the oral health assessment (OHA), 2525 were examined. Adults below 50 years of age (n=17) and 4 respondents whose oral health data were unavailable at time of analysis were omitted, giving a final sample of 2504 respondents.  Among the OHA sample, 9.9% (249) were edentate; 11.5% (159) of females and 8% (90) of males. Of those aged 65 years and older, 15.6% were edentate compared with 40.9% in 2000-02. The mean number of teeth present in those aged 65 years or older was 14.9 for males and 14.2 for females compared with 9.9 and 7.4, respectively, in 2000-02. 56.8% of the dentate sample had 10 or more tooth contacts. The mean DMFT of those aged 50 years or more was 18.5 and the Root Caries Index (RCI) was 6.3. For adults aged 65 years and over, the mean DMFT decreased from 25.9 to 20.1 and the Root Caries Index decreased from 11.6 to 9.1, between 2000-02 and 2014-15. Conclusion: The results suggest an improvement in oral health status of community dwelling adults aged 50 years and over in Ireland as compared to the previous Irish survey of 2000-02.

Novel multiresistance cfr plasmids in linezolid-resistant methicillin-resistant Staphylococcus epidermidis and vancomycin-resistant Enterococcus faecium (VRE) from a hospital outbreak: co-location of cfr and optrA in VRE

Background

Linezolid is often the drug of last resort to treat infections caused by Gram-positive cocci. Linezolid resistance can be mutational (23S rRNA or L-protein) or, less commonly, acquired [predominantly cfr, conferring resistance to phenicols, lincosamides, oxazolidinones, pleuromutilins and streptogramin A compounds (PhLOPSA) or optrA, encoding oxazolidinone and phenicol resistance].

Objectives

To investigate the clonality and genetic basis of linezolid resistance in 13 linezolid-resistant (LZDR) methicillin-resistant Staphylococcus epidermidis (MRSE) isolates recovered during a 2013/14 outbreak in an ICU in an Irish hospital and an LZDR vancomycin-resistant Enterococcus faecium (VRE) isolate from an LZDR-MRSE-positive patient.

Methods

All isolates underwent PhLOPSA susceptibility testing, 23S rRNA sequencing, DNA microarray profiling and WGS.

Results

All isolates exhibited the PhLOPSA phenotype. The VRE harboured cfr and optrA on a novel 73 kb plasmid (pEF12-0805) also encoding erm(A), erm(B), lnu(B), lnu(E), aphA3 and aadE. One MRSE (M13/0451, from the same patient as the VRE) harboured cfr on a novel 8.5 kb plasmid (pSEM13-0451). The remaining 12 MRSE lacked cfr but exhibited linezolid resistance-associated mutations and were closely related to (1-52 SNPs) but distinct from M13/0451 (202-223 SNPs).

Conclusions

Using WGS, novel and distinct cfr and cfr/optrA plasmids were identified in an MRSE and VRE isolate, respectively, as well as a cfr-negative LZDR-MRSE ICU outbreak and a distinct cfr-positive LZDR-MRSE from the same ICU. To our knowledge, this is the first report of cfr and optrA on a single VRE plasmid. Ongoing surveillance of linezolid resistance is essential to maintain its therapeutic efficacy.

Post-influenzal triazole-resistant aspergillosis following allogeneic stem cell transplantation

Influenza virus infection is now recognised as a risk factor for invasive pulmonary aspergillosis (IPA). Delays in diagnosis contribute to delayed commencement of antifungal therapy. In addition, the emergence of resistance to first-line triazole antifungal agents puts emphasis on early detection to prevent adverse outcomes. We present 2 allogeneic stem cell transplant patients who developed IPA due to triazole-resistant Aspergillus fumigatus following influenza infection. We underline the challenges faced in the management of these cases, the importance of early diagnosis and need for surveillance given the emergence of triazole resistance.

An assessment of professionalism on students' Facebook profiles

INTRODUCTION

With the advent of social media, healthcare professionals not only need to be conscious of professionalism in their face-to-face interactions but also in the electronic environment. The aim of this study was to assess the level of online professionalism on Facebook profiles available for public viewing of students from a dental school.

MATERIALS AND METHODS

A search was performed via a new Facebook account of all students in the University Dental School (dental hygiene, dental nursing, dental science and dental technology). Profiles were categorised as 'private' or 'public'. Demographic details and photographs/comments of unprofessional behaviour were recorded for each individual Facebook profile. Each profile was subsequently scored with regard to professionalism based on a previously published score.

RESULTS

There are a total of 287 students in the dental school. Of these, 62% (n = 177) had a Facebook account. Three per cent (n = 6) had a public account (fully accessible) whilst 97% (n = 171) had a private account (limited access); 36% (n = 63) of students mentioned the dental school/hospital on their profile; 34% (n = 60) had questionable content on their profile whilst 3% (n = 6) had definite violations of professionalism on their profile; and 25% (n = 44) had unprofessional photographs on their profile. Of those with unprofessional content, 52% (n = 23) of these had a documented affiliation with the dental school also visible on their profile.

CONCLUSION

There was a concerning level of unprofessional content visible on students' Facebook profiles. Students need to be fully aware of their professional responsibility in the setting of social media.

Multidisciplinary Management of Hypodontia

Patients with hypodontia require a wide range of treatment, ranging from single tooth replacement to the restoration of multiple edentulous spaces in both arches. Treatment should involve an interdisciplinary team, as no dental speciality possesses the range of expertise required to optimally treat this patient population. This paper presents principles of treatment, key factors of assessment and multidisciplinary approaches to management of the hypodontia patient, including contributions from conservative dentistry.

Microplastics in Sewage Sludge: Effects of Treatment

Waste water treatment plants (WWTPs) are receptors for the cumulative loading of microplastics (MPs) derived from industry, landfill, domestic wastewater and stormwater. The partitioning of MPs through the settlement processes of wastewater treatment results in the majority becoming entrained in the sewage sludge. This study characterized MPs in sludge samples from seven WWTPs in Ireland which use anaerobic digestion (AD), thermal drying (TD), or lime stabilization (LS) treatment processes. Abundances ranged from 4196 to 15 385 particles kg^-1 (dry weight). Results of a general linear mixed model (GLMM) showed significantly higher abundances of MPs in smaller size classes in the LS samples, suggesting that the treatment process of LS shears MP particles. In contrast, lower abundances of MPs found in the AD samples suggests that this process may reduce MP abundances. Surface morphologies examined using scanning electron microscopy (SEM) showed characteristics of melting and blistering of TD MPs and shredding and flaking of LS MPs. This study highlights the potential for sewage sludge treatment processes to affect the risk of MP pollution prior to land spreading and may have implications for legislation governing the application of biosolids to agricultural land.

Efficacy of the Nance appliance as an anchorage-reinforcement method

INTRODUCTION

The Nance appliance is widely considered to be an efficient method of anchorage reinforcement; however, much of the perceived advantage is based on clinical judgment. The aim of this study was to assess the amounts of anchorage loss and desired tooth movement associated with the Nance appliance.

METHODS

The mandibular arches of 7 beagle dogs were used. The first and third premolars were extracted. Reference miniscrews were placed at the first premolar sites as stable references to measure the amounts of anchorage loss and desired tooth movement. Four beagles were fitted with custom-made Nance appliances on the fourth premolars and orthodontic bands on the second premolars (Nance group). Three beagles were fitted with orthodontic bands on the second and fourth premolars with no anchorage reinforcement (control group). The second premolars were retracted over 15 weeks in both groups. The amounts of second premolar movement (desired tooth movement) and fourth premolar movement (anchorage loss) were recorded at 5, 10, and 15 weeks. The percentages of desired tooth movement and anchorage loss to the total space closure were calculated.

RESULTS

The mean desired tooth movement was significantly more in the Nance group than in the control group at 10 weeks (P <0.05) but was not significantly different at 5 and 15 weeks. The mean percentages of anchorage loss to the total space closure at 15 weeks were 45.7% in the control group and 28.8% in the Nance group. The Nance group had 16.9% less anchorage loss and 16.6% more desired tooth movement than did the control group at 15 weeks (P <0.05). Most of the anchorage loss (80%) in the Nance group occurred during the first 10 weeks.

CONCLUSIONS

The Nance appliance did not provide absolute anchorage, but there was significantly less anchorage loss with it than in the control group. The majority of anchorage loss occurred during the first 10 weeks in the Nance group.

Ongoing challenges responding to behavioural and psychological symptoms of dementia

BACKGROUND

Mid- to late-stage dementia is often characterized by behavioural and psychological symptoms, including, but not limited to physical and verbal aggression.

INTRODUCTION

Although there is a considerable research about the prevalence, aetiology, and management of behavioural and psychological symptoms of dementia, there is limited research about the experience of caring for people with such symptoms in long-term aged care facilities.

AIM

The aims of the study were to describe: (i) nurses' experiences of caring for people with behavioural and psychological symptoms of dementia in long-term aged care facilities, and (ii) strategies nurses used to deal with these symptoms.

METHODS

A qualitative exploratory and descriptive design, involving focus group interviews with 30 nurses from three long-term aged care units in Australia. The transcripts were analysed using inductive content analysis.

RESULTS

The findings revealed five interrelated themes: (i) working under difficult conditions, (ii) behavioural and psychological symptoms of dementia: an everyday encounter, (iii) making sense of behavioural and psychological symptoms of dementia, (iv) attempting to manage behavioural and psychological symptoms of dementia, and (v) feeling undervalued.

CONCLUSION

This study highlighted the difficult conditions under which nurses worked and the complexity of caring for individuals who have behavioural and psychological symptoms of dementia.

IMPLICATIONS FOR NURSING AND HEALTH POLICY

Organizational efforts to enhance the quality of care for individuals with behavioural and psychological symptoms of dementia in long-term aged care facilities should extend beyond staff education to heed nurses' concerns about organizational barriers to interpersonal care.

Dialectical behaviour therapy (DBT) in the treatment of borderline personality disorder

Borderline personality disorder (BPD) is a complex disorder that is difficult to treat. However, dialectical behaviour therapy (DBT), developed by Dr. Marsha Linehan in the early 1990s, has emerged as a promising treatment option for those diagnosed with BPD. DBT is a multi-pronged treatment approach delivered normally in outpatient settings over 12 months and requires highly skilled and trained therapists. Many trials have provided evidence to support the use of DBT in the treatment of BPD. However, outcome measures vary and are mostly limited to measurable behavioural outcomes such as incidences of deliberate self-harm or suicidal thoughts. Two recent Cochrane reviews conclude that DBT does benefit those with BPD, but more robust evidence is needed. DBT training for health care professionals also has the potential to shift health care professionals' attitudes from one of therapeutic pessimism to one of optimism.

Infection of the Beard area. Kerion: a review of 2 cases

Folliculitis barbae is a common condition of both infective and non-infectious aetiology. It most frequently presents as a superficial folliculitis, with fine pustules appearing at the opening of hair follicles in the beard area, often associated with shaving; known as Bockhart impetigo and usually due to infection caused by Staphylococcus aureus. If untreated, the infection and inflammation can progress, leading to a more deeply seated infection known as sycosis barbae. Perifollicular nodules, termed furuncles, may appear and when these are multiple and coalesce, a deep-seated, communicating, pustulating plaque called a carbuncle develops, often with associated systemic upset. Such an appearance, which can prompt incision and drainage, should not, however, be assumed to be solely due to staphylococcal infection. Particularly in the context of a history of close animal contact or a lack of response to antibiotic treatment, a diagnosis of tinea barbae should be considered and investigated. Prompt treatment with antifungal agents and often systemic steroids is required once the diagnosis is made. This will help reduce an exacerbation of the pronounced destruction that results from the immune response to the fungal infection, known as a kerion, which would be compounded by surgical intervention. In this article, we review two such cases and review the investigation and management of the disease.

Infectious disease outbreaks in competitive sports, 2005-2010

CONTEXT

Old, evolving, and new infectious agents continually threaten the participation of competitors in sports.

OBJECTIVE

To provide an update of the medical literature on infectious disease outbreaks in sport for the last 5 years (May 2005-November 2010).

MAIN OUTCOME MEASURE(S)

A total of 21 outbreaks or clusters were identified.

RESULTS

Methicillin-resistant Staphylococcus aureus (n = 7, 33%; mainly community acquired) and tinea (trichophytosis: n = 6, 29%) were the most common pathogens responsible for outbreaks. Skin and soft tissue was the most common site of infection (n = 15, 71%).

CONCLUSIONS

The majority of outbreaks reported occurred in close-contact sports, mainly combat sports (ie, wrestling, judo) and American football. Twelve outbreaks (57%) involved high school or collegiate competitors. Common community outbreak pathogens, such as influenza virus and norovirus, have received little attention.

A radiographic analysis of implant component misfit

PURPOSE

Radiographs are commonly used to assess the fit of implant components, but there is no clear agreement on the amount of misfit that can be detected by this method. This study investigated the effect of gap size and the relative angle at which a radiograph was taken on the detection of component misfit. Different types of implant connections (internal or external) and radiographic modalities (film or digital) were assessed.

MATERIALS AND METHODS

Twelve internal-connection and 12 external-connection implant analogs with impression copings were assembled, with radiolucent washers interposed, to produce vertical misfits of 0, 12.7, 25, 38, 51, 63, 76, 88, 102, 114, 127, and 190 μm. A custom-made positioning apparatus was used to obtain radiographs of the components at angulations between 0 and 35 degrees. The images were randomized, and three experienced examiners assessed whether a gap was visible at the interface. Their responses were compared to the actual status of the samples, and a probability model was constructed to predict the likelihood of a correct answer at any combination of gap and angle.

RESULTS

The relative angulation of the radiograph and the dimension of the gap were the most significant factors affecting an examiner's diagnostic ability. A 0-μm gap viewed at 0 degrees was the combination most accurately diagnosed. Implant component misfits as small as 12.7 μm were reliably detected with radiographs up to 5 degrees from the orthogonal projection; this was similar with configurations of 25 to 38 μm/10 degrees and 51 μm/15 degrees. There was good (inter-)examiner reliability. Neither the type of component used nor the radiographic media used influenced diagnostic ability.

CONCLUSION

The angulation of the x-ray beam relative to implant components needs to be controlled when using radiographs to detect component misfit.